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Achyrocline satureioides , popularly called "marcela" in Brazil, is used in traditional medicine in South America. A. satureioides , inflorescences are used for many conditions, including to minimize the Sars-Cov-2 symptoms. Therefore, the aim of this study was to determine the toxicity profile of A. satureioides aqueous extract (ASAE), using the Caenorhabditis elegans ( C. elegans ) alternative model. Survival, reproduction, development, and transgenerational assays were performed. The effects of ASAE were investigated under conditions of thermal stress and presence of oxidant hydrogen peroxide (H 2 O 2 ). In addition, C. elegans strains containing high antioxidant enzyme levels and elevated lineages of daf-16, skn-1 and daf-2 regulatory pathways were examined. The ASAE LC 50 value was found to be 77.3 ± 4 mg/ml. The concentration of ASAE 10 mg/ml (frequently used in humans) did not exhibit a significant reduction in worm survival at either the L1 or L4 stage, after 24 or 72 hr treatment. ASAE did not markedly alter the body area. In N2 strain, ASAE (10 or 25 mg/ml) reversed the damage initiated by H 2 O 2 . In addition, ASAE protected the damage produced by H 2 O 2 in strains containing significant levels of sod -3, gst -4 and ctl - 1,2,3, suggesting modulation in these antioxidant systems by this plant extract. ASAE exposure activated daf-16 and skn-1 stress response transcriptional pathways independently of daf-2 , even under extreme stress. Data suggest that ASAE, at the concentrations tested in C. elegans , exhibits a reliable toxicity profile, which may contribute to consideration for safe use in humans.

The accumulation of SIRT4 in the nuclei of kidney cells drives kidney fibrosis, so blocking the movement of this protein could be a potential therapeutic strategy against fibrosis., Competing Interests: KZ, ZZ No competing interests declared, (© 2024, Zhao and Zhou.)

Pancreatic ductal adenocarcinoma (PDAC) poses a formidable challenge in oncology due to its limited treatment options and poor long-term survival rates. Our previous work identified MG53, a member of the tripartite motif family protein (TRIM72), as a key player in tissue repair with potential applications in regenerative medicine. Despite the focus on MG53's cytosolic functions, its nuclear role in suppressing pancreatic cancer remains unknown. Through orthotopic and subcutaneous transplantation studies in mice, we observed enhanced tumor growth in MG53-deficient mice compared to wild-type counterparts. The overexpression of KIF11, a motor protein crucial for cell mitosis regulation, has been linked to the aggressive proliferation of pancreatic cancer cells. Confocal imaging confirmed MG53's presence in the nucleus of human pancreatic cancer cells, while functional assays demonstrated its impact on KIF11 expression and subsequent cell proliferation. Mechanistically, we revealed MG53's transcriptional control over KIF11, leading to cell cycle arrest. Our findings position MG53 as a promising tumor suppressor in PDAC, offering a novel avenue for therapeutic intervention by regulating KIF11 expression., Competing Interests: Declaration of competing interest Dr. Jianjie Ma (J.M.) is founder of TRIM-edicine, which develops MG53 for the treatment of human disease. Patents on the use of MG53 are held by Rutgers University-Robert Wood Johnson Medical School and The Ohio State University., (Copyright © 2024. Published by Elsevier Inc.)

The nucleolar localization of proteins is regulated by specific signals directing their trafficking to nucleus and nucleolus. Here, we elucidate the mechanism underlying the nuclear and nucleolar localization of the nucleomethylin (NML) protein, focusing on its nuclear localization signals (NLSs) and nucleolar localization signal (NoLS). Using a combination of bioinformatic analysis and experimental validation, we identified two monopartite and one bipartite NLS motifs within NML. The combined presence of both monopartite NLSs significantly enhances nuclear localization of the protein, while specific basic amino acid clusters within the bipartite NLS are crucial for their functionality. We also reveal the functional role of the NLS-coupled NoLS motif in driving nucleolar localization of NML, which contains an arginine-rich motif essential for its function. The basic residues of the arginine-rich motif of NoLS of NML interacts with nucleophosmin 1 (NPM1), allowing the possible liquid-liquid phase separation and retention of NML in the nucleolus. Remarkably, the strong NoLS of NML can direct the nucleolar localization of a cytosolic protein, aldolase, emphasizing its potency. Overall, our findings provide insights into the combinatorial functioning of NLSs and NoLS in regulating the subcellular localization of NML, highlighting the intricate regulatory mechanisms governing its localization within the nucleus and nucleolus., (© 2024 Wiley Periodicals LLC.)

Duchenne muscular dystrophy (DMD) is an X-linked recessive progressive degenerative disease of skeletal muscle, characterized by intramuscular inflammation, muscle regeneration disorder and replacement of muscle with fibroadipose tissue. DMD is caused by the absence of normal dystrophy. Impaired self-renew ability and limited differentiation capacity of satellite cells are proved as main reasons for muscle regeneration failure. The deficiency of estrogen impedes the process of muscle regeneration. However, the role of estrogen receptor β (ERβ) in muscle regeneration is still unclear. This study aims to investigate the role and the pharmacological effect of ERβ activation on muscle regeneration in mdx mice. This study showed that mRNA levels of ERβ and myogenic-related genes both witnessed increasing trends in dystrophic context. Our results revealed that treatment with selective ERβ agonist (DPN, diarylpropionitrile) significantly increased myogenic differentiation 1 (MyoD-1) level and promoted muscle regeneration in mdx mice. Similarly, in mdx mice with muscle-specific estrogen receptor α (ERα) ablation, DPN treatment still promoted muscle regeneration. Moreover, we demonstrated that myoblasts differentiation was accompanied by raised nuclear accumulation of ERβ. DPN treatment augmented the nuclear accumulation of ERβ and, thus, contributed to myotubes formation. One important finding was that forkhead box O3A (FOXO3A), as a pivotal transcription factor in Myod-1 transcription, participated in the ERβ-promoted muscle regeneration. Overall, we offered an interesting explanation about the crucial role of ERβ during myogenesis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The key role of structural cells in immune modulation has been revealed with the advent of single-cell multiomics, but the underlying mechanism remains poorly understood. Here, we revealed that the transcriptional activation of interferon regulatory factor 1 (IRF1) in response to ionizing radiation, cytotoxic chemicals and SARS-CoV-2 viral infection determines the fate of structural cells and regulates communication between structural and immune cells. Radiation-induced leakage of mtDNA initiates the nuclear translocation of IRF1, enabling it to regulate the transcription of inflammation- and cell death-related genes. Novel posttranslational modification (PTM) sites in the nuclear localization sequence (NLS) of IRF1 were identified. Functional analysis revealed that mutation of the acetylation site and the phosphorylation sites in the NLS blocked the transcriptional activation of IRF1 and reduced cell death in response to ionizing radiation. Mechanistically, reciprocal regulation between the single-stranded DNA sensors SSBP1 and IRF1, which restrains radiation-induced and STING/p300-mediated PTMs of IRF1, was revealed. In addition, genetic deletion or pharmacological inhibition of IRF1 tempered radiation-induced inflammatory cell death, and radiation mitigators also suppressed SARS-CoV-2 NSP-10-mediated activation of IRF1. Thus, we revealed a novel cytoplasm-oriented mechanism of IRF1 activation in structural cells that promotes inflammation and highlighted the potential effectiveness of IRF1 inhibitors against immune disorders., (© 2024. The Author(s), under exclusive licence to CSI and USTC.)

Activating transcription factor 6 (ATF6) and its downstream genes are involved in progression of hepatocellular carcinoma (HCC). Herein, we demonstrated that sulfhydration of Ras-related protein Rab-7a (RAB7A) was regulated by ATF6. High expression of RAB7A indicated poor prognosis of HCC patients. RAB7A overexpression contributed to proliferation, colony formation, migration, and invasion of HepG2 and Hep3B cells. Furthermore, we found that RAB7A enhanced aerobic glycolysis in HepG2 cells, indicating a higher degree of tumor malignancy. Mechanistically, RAB7A suppressed Yes-associated protein 1 (YAP1) binding to 14-3-3 and conduced to YAP1 nuclear translocation and activation, promoting its downstream gene expression, thereby promoting growth and metastasis of liver cancer cells. In addition, knocking down RAB7A attenuated the progression of orthotopic liver tumors in mice. These findings illustrate the important role of RAB7A in regulating HCC progression. Thus, RAB7A may be a potential innovative target for HCC treatment., (© 2024 Wiley Periodicals LLC.)

Breast tumor-initiating cells (BTICs) of triple-negative breast cancer (TNBC) tissues actively repair DNA and are resistant to treatments including chemotherapy, radiotherapy, and targeted therapy. Herein, it is found that a previously reported secreted protein, sclerostin domain containing 1 (SOSTDC1), is abundantly expressed in BTICs of TNBC cells and positively correlated with a poor patient prognosis. SOSTDC1 knockdown impairs homologous recombination (HR) repair, BTIC maintenance, and sensitized bulk cells and BTICs to Olaparib. Mechanistically, following Olaparib treatment, SOSTDC1 translocates to the nucleus in an importin-α dependent manner. Nuclear SOSTDC1 interacts with the N-terminus of the nucleoprotein, chromatin helicase DNA-binding factor (CHD1), to promote HR repair and BTIC maintenance. Furthermore, nuclear SOSTDC1 bound to β-transducin repeat-containing protein (β-TrCP) binding motifs of CHD1 is found, thereby blocking the β-TrCP-CHD1 interaction and inhibiting β-TrCP-mediated CHD1 ubiquitination and degradation. Collectively, these findings identify a novel nuclear SOSTDC1 pathway in regulating HR repair and BTIC maintenance, providing insight into the TNBC therapeutic strategies., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

The pyruvate dehydrogenase complex (PDC) is remarkable for its size and structure as well as for its physiological and pathological importance. Its canonical location is in the mitochondrial matrix, where it primes the tricarboxylic acid (TCA) cycle by decarboxylating glycolytically-derived pyruvate to acetyl-CoA. Less well appreciated is its role in helping to shape the epigenetic landscape, from early development throughout mammalian life by its ability to "moonlight" in the nucleus, with major repercussions for human healthspan and lifespan. The PDC's influence on two crucial modifiers of the epigenome, acetylation and lactylation, is the focus of this brief review., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier Inc.)

Signal recognition particles (SRPs) are essential for regulating intracellular protein transport and secretion. Patients with tumors with high SRP9 expression tend to have a poorer overall survival. However, to the best of our knowledge, no reports have described the relationship between SRP9 localization and prognosis in pancreatic cancer. Thus, the present study aimed to investigate this relationship. Immunohistochemical staining for SRP9 using excised specimens from pancreatic cancer surgery cases without preoperative chemotherapy or radiotherapy showed that SRP9 was preferentially expressed in the nucleus of the cancerous regions in some cases, which was hardly detected in other cases, indicating that SRP9 was transported to the nucleus in the former cases. To compare the prognosis of patients with SRP9 nuclear translocation, patients were divided into two groups: Those with a nuclear translocation rate of >50% and those with a nuclear translocation rate of ≤50%. The nuclear translocation rate of >50% group had a significantly better recurrence‑free survival than the nuclear translocation rate of ≤50% group (P=0.037). Subsequent in vitro experiments were conducted; notably, the nuclear translocation rate of SRP9 was reduced under amino acid‑deficient conditions, suggesting that multiple factors are involved in this phenomenon. To further study the function of SRP9 nuclear translocation, in vitro experiments were performed by introducing SRP9 splicing variants (v1 and v2) and their deletion mutants lacking C‑terminal regions into MiaPaCa pancreatic cancer cells. The results demonstrated that both splicing variants showed nuclear translocation regardless of the C‑terminal deletions, suggesting the role of the N‑terminal regions. Given that SRP9 is an RNA‑binding protein, the study of RNA immunoprecipitation revealed that signaling pathways involved in cancer progression and protein translation were downregulated in nuclear‑translocated v1 and v2. Undoubtedly, further studies of the nuclear translocation of SRP9 will open an avenue to optimize the precise evaluation and therapeutic control of pancreatic cancer.

Introduction: Despite radiotherapy being one of the major treatments for triple-negative breast cancer (TNBC), new molecular targets for its treatment are still required due to radioresistance. CDK2 plays a critical role in TNBC. However, the mechanism by which CDK2 promotes TNBC radioresistance remains to be clearly elucidated., Objectives: We aimed to elucidate the relationship between CDK2 and TRIM32 and the regulation mechanism in TNBC., Methods: We performed immunohistochemical staining to detect nuclear TRIM32, CDK2 and STAT3 on TNBC tissues. Western blot assays and PCR were used to detect the protein and mRNA level changes. CRISPR/Cas9 used to knock out CDK2. shRNA-knockdown and transfection assays also used to knock out target genes. GST pull-down analysis, immunoprecipitation (IP) assay and in vitro isomerization analysis also used. Tumorigenesis studies also used to verify the results in vitro., Results: Herein, tripartite motif-containing protein 32 (TRIM32) is revealed as a substrate of CDK2. Radiotherapy promotes the binding of CDK2 and TRIM32, thus leading to increased CDK2-dependent phosphorylation of TRIM32 at serines 328 and 339. This causes the recruitment of PIN1, involved in cis-trans isomerization of TRIM32, resulting in importin α3 binding to TRIM32 and contributing to its nuclear translocation. Nuclear TRIM32 inhibits TC45-dephosphorylated STAT3, Leading to increased transcription of STAT3 and radioresistance in TNBC. These results were validated by clinical prognosis confirmed by the correlative expressions of the critical components of the CDK2/TRIM32/STAT3 signaling pathway., Conclusions: Our findings demonstrate that regulating the CDK2/TRIM32/STAT3 pathway is a promising strategy for reducing radioresistance in TNBC., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

Background: Osteoarthritis (OA) is a progressive condition affecting the joints that lacking effective therapy. However, the underlying molecular mechanism has not been fully clarified., Methods: A model of OA was established in Sprague-Dawley (SD) rats through intra-articularly injected with monoiodoacetate (MIA). Western blot analysis was used to identify the levels of UBE2I and hnRNPA2B1 in articular cartilage. Overexpression and siRNA vectors for UBE2I were constructed and transfected into rat chondrocytes. CCK-8, TUNEL and transwell assay were utilized to assess the cell viability, apoptosis and migration ability. Western blot analysis was used to determine the levels of chondrogenic-specific genes including SOX9, COL2A1, Aggrecan, and PRG4. Then, molecular interactions were confirmed by immunoprecipitation., Results: We observed significant upregulation of UBE2I and hnRNPA2B1 expression in articular cartilage samples of OA. The Pearson correlation analysis revealed positive correlation between UBE2I and hnRNPA2B1 levels. Functional experiments showed that increased UBE2I expression significantly suppressed cell growth, migration, and reduced the expression of chondrogenic-specific genes, while decreasing UBE2I levels had the opposite effects. Molecular interactions between UBE2I and hnRNPA2B1were determined via co-localization and immunoprecipitation. SUMO1 and SUMO3 proteins were enriched by immunoprecipitation using hnRNPA2B1 antibodies. Rescue experiments were performed using SUMOylation inhibitor (2-D08) and SUMOylation activator (N106). Overexpression of UBE2I increased the expression of hnRNPA2B1 in the cytoplasm and decreased the level in the nucleus, which was reversed by the treatment of 2-D08. Conversely, UBE2I knockdown and N106 treatment had the opposite effect., Conclusions: UBE2I modulated the nuclear translocation of hnRNPA2B1 by promoting SUMOylation in OA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Wnt/Wingless (Wg) signaling is critical in development and disease, including cancer. Canonical Wnt signaling is mediated by β-catenin/Armadillo (Arm in Drosophila) transducing signals to the nucleus, with IFT-A/Kinesin 2 complexes promoting nuclear translocation of β-catenin/Arm. Here, we demonstrate that a conserved small N-terminal Arm 34 - 87 inhibits Wg/Wnt signaling by interfering with nuclear translocation of endogenous Arm/β-catenin, and this can be modulated by levels of wild-type β-catenin or IFT140, with the Arm 34 - peptide blocking nuclear translocation and pathway activation, including in cancer cells. Our work indicates that Wnt signaling can be regulated by a defined N-terminal β-catenin peptide and thus might serve as an entry point for therapeutic applications to attenuate Wnt/β-catenin signaling.87 expression antagonizes endogenous Wnt/Wg signaling, resulting in the reduction of its target expression. Arm 34 - 87 inhibits Wg/Wnt signaling by interfering with nuclear translocation of endogenous Arm/β-catenin, and this can be modulated by levels of wild-type β-catenin or IFT140, with the Arm 34 - 87 effect being enhanced or suppressed. Importantly, this mechanism is conserved in mammals with the equivalent β-catenin 24 - 79 peptide blocking nuclear translocation and pathway activation, including in cancer cells. Our work indicates that Wnt signaling can be regulated by a defined N-terminal β-catenin peptide and thus might serve as an entry point for therapeutic applications to attenuate Wnt/β-catenin signaling., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Long-term denervation-induced atrophy and fibrosis of skeletal muscle due to denervation leads to poor recovery of muscle function. Studies have shown that the transforming growth factor-β1 (TGF-β1)-Smad signaling pathway plays a central role in muscle atrophy and fibrosis. Recent studies demonstrate the role of microRNAs (miRs) in various pathological conditions, including muscle regeneration. miR-21 has been shown to play a dynamic role in inflammatory responses and in accelerating injury responses to fibrosis. We used both RNA sequencing and quantitative RT-PCR strategies to examine the alternations of miRNAs during denervation-induced gastrocnemius muscle atrophy and fibrosis. Our data showed that MiR-21 was upregulated in denervated gastrocnemius muscle tissue, and TGF-β1treatment increased miR-21 expression. Inhibition of miR-21 reduced gastrocnemius muscle fibrosis and significantly downregulated the expression of p -SMAD2/3 and the fibrosis-associated markers TGF-β1, connective tissue growth factor, alpha smooth muscle actin. Masson's trichrome staining revealed that atrophy and fibrosis in gastrocnemius muscle tissue were reduced in the miR-21 inhibition group compared to the control group. We confirmed that SMAD7 is a direct target of miR-21 using a dual luciferase assay. Furthermore, Immunofluorescence and Western blot analyses revealed that miR-21 inhibition reduced SMAD2/3 phosphorylation and nuclear translocation. While SMAD7-siRNA abolished the effect. Consequently, the discovery that miR-21 regulates the atrophy and fibrosis of the gastrocnemius muscle offers a possible therapeutic approach for their management., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: ShicaiChen reports financial support was provided by 10.13039/501100001809National Natural Science Foundation of China. Hongliang Zheng reports financial support was provided by 10.13039/501100001809National Natural Science Foundation of China. Xianmin Song reports financial support was provided by 10.13039/501100001809National Natural Science Foundation of China. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Human respiratory viruses are the most prevalent cause of disease in humans, with the highly infectious RSV being the leading cause of infant bronchiolitis and viral pneumonia. Responses to type I IFNs are the primary defense against viral infection. However, RSV proteins have been shown to antagonize type I IFN-mediated antiviral innate immunity, specifically dampening intracellular IFN signaling. Respiratory epithelial cells are the main target for RSV infection. In this study, we found RSV-NS1 interfered with the IFN-α JAK/STAT signaling pathway of epithelial cells. RSV-NS1 expression significantly enhanced IFN-α-mediated phosphorylation of STAT1, but not pSTAT2; and neither STAT1 nor STAT2 total protein levels were affected by RSV-NS1. However, expression of RSV-NS1 significantly reduced ISRE and GAS promoter activity and anti-viral IRG expression. Further mechanistic studies demonstrated RSV-NS1 bound STAT1, with protein modeling indicating a possible interaction site between STAT1 and RSV-NS1. Nuclear translocation of STAT1 was reduced in the presence of RSV-NS1. Additionally, STAT1's interaction with the nuclear transport adapter protein, KPNA1, was also reduced, suggesting a mechanism by which RSV blocks STAT1 nuclear translocation. Indeed, reducing STAT1's access to the nucleus may explain RSV's suppression of IFN JAK/STAT promoter activation and antiviral gene induction. Taken together these results describe a novel mechanism by which RSV controls antiviral IFN-α JAK/STAT responses, which enhances our understanding of RSV's respiratory disease progression., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Efstathiou, Zhang, Kandwal, Fayne, Molloy and Stevenson.)

As is well known, apoptosis is an important form of immune response and immune regulation, particularly playing a crucial role in combating microbial infections. Apoptosis-inducing factor 1 (AIF-1) is essential for apoptosis to induce chromatin condensation and DNA fragmentation via a caspase-independent pathway. The nuclear translocation of AIF-1 is a key step in apoptosis but the molecular mechanism is still unclear. In this study, the homologous gene of AIF-1, named AjAIF-1, was cloned and identified in Apostichopus japonicus. The mRNA expression of AjAIF-1 was significantly increased by 46.63-fold after Vibrio splendidus challenge. Silencing of AjAIF-1 was found to significantly inhibit coelomocyte apoptosis because the apoptosis rate of coelomocyte decreased by 0.62-fold lower compared with the control group. AjAIF-1 was able to promote coelomocyte apoptosis through nuclear translocation under the V. splendidus challenge. Moreover, AjAIF-1 and Ajimportin β were mainly co-localized around the nucleus in vivo and silencing Ajimportin β significantly inhibited the nuclear translocation of AjAIF-1 and suppressed coelomocyte apoptosis by 0.64-fold compared with control. In summary, nuclear translocation of AjAIF-1 will likely mediate coelomocyte apoptosis through an importin β-dependent pathway in sea cucumber., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a crucial enzyme in glycolysis, an essential metabolic pathway for carbohydrate metabolism across all living organisms. Recent research indicates that phosphorylating GAPDH exhibits various moonlighting functions, contributing to plant growth and development, autophagy, drought tolerance, salt tolerance, and bacterial/viral diseases resistance. However, in rapeseed ( Brassica napus ), the role of GAPDHs in plant immune responses to fungal pathogens remains unexplored. In this study, 28 genes encoding GAPDH proteins were revealed in B. napus and classified into three distinct subclasses based on their protein structural and phylogenetic relationships. Whole-genome duplication plays a major role in the evolution of BnaGAPDHs . Synteny analyses revealed orthologous relationships, identifying 23, 26, and 26 BnaGAPDH genes with counterparts in Arabidopsis , Brassica rapa , and Brassica oleracea , respectively. The promoter regions of 12 BnaGAPDHs uncovered a spectrum of responsive elements to biotic and abiotic stresses, indicating their crucial role in plant stress resistance. Transcriptome analysis characterized the expression profiles of different BnaGAPDH genes during Sclerotinia sclerotiorum infection and hormonal treatment. Notably, BnaGAPDH17 , BnaGAPDH20 , BnaGAPDH21 , and BnaGAPDH22 exhibited sensitivity to S. sclerotiorum infection, oxalic acid, hormone signals. Intriguingly, under standard physiological conditions, BnaGAPDH17 , BnaGAPDH20 , and BnaGAPDH22 are primarily localized in the cytoplasm and plasma membrane, with BnaGAPDH21 also detectable in the nucleus. Furthermore, the nuclear translocation of BnaGAPDH20 was observed under H 2 O 2 treatment and S. sclerotiorum infection. These findings might provide a theoretical foundation for elucidating the functions of phosphorylating GAPDH., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Xu, Wang, Zhang, Zhuang, Zhang, Lin, Zhan, Chen, Lu, Wang and Liao.)

Ethnopharmacological Relevance: Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and arthritic pain. Sinomenine (SIN), derived from the rhizome of Chinese medical herb Qing Teng (scientific name: Sinomenium acutum (Thunb.) Rehd. Et Wils), has a longstanding use in Chinese traditional medicine for treating rheumatoid arthritis. It has been shown to possess anti-inflammatory, analgesic, and immunosuppressive effects with minimal side-effects clinically. However, the mechanisms governing its effects in treatment of joint pathology, especially on fibroblast-like synoviocytes (FLSs) dysfunction, and arthritic pain remains unclear., Aim: This study aimed to investigate the effect and underlying mechanism of SIN on arthritic joint inflammation and joint FLSs dysfunctions., Materials and Methods: Collagen-induced arthritis (CIA) was induced in rats and the therapeutic effects of SIN on joint pathology were evaluated histopathologically. Next, we conducted a series of experiments using LPS-induced FLSs, which were divided into five groups (Naïve, LPS, SIN 10, 20, 50 μg/ml). The expression of inflammatory factors was measured by qPCR and ELISA. The invasive ability of cells was detected by modified Transwell assay and qPCR. Transwell migration and cell scratch assays were used to assess the migration ability of cells. The distribution and content of relevant proteins were observed by immunofluorescence and laser confocal microscopy, as well as Western Blot and qPCR. FLSs were transfected with plasmids (CRMP2 T514A/D) to directly modulate the post-translational modification of CRMP2 protein and downstream effects on FLSs function was monitored., Results: SIN alleviated joint inflammation in rats with CIA, as evidenced by improvement of synovial hyperplasia, inflammatory cell infiltration and cartilage damage, as well as inhibition of pro-inflammatory cytokines release from FLSs induced by LPS. In vitro studies revealed a concentration-dependent suppression of SIN on the invasion and migration of FLSs induced by LPS. In addition, SIN downregulated the expression of cellular CRMP2 that was induced by LPS in FLSs, but increased its phosphorylation at residue T514. Moreover, regulation of pCRMP2 T514 by plasmids transfection (CRMP2 T514A/D) significantly influenced the migration and invasion of FLSs. Finally, SIN promoted nuclear translocation of pCRMP2 T514 in FLSs., Conclusions: SIN may exert its anti-inflammatory and analgesic effects by modulating CRMP2 T514 phosphorylation and its nuclear translocation of FLSs, inhibiting pro-inflammatory cytokine release, and suppressing abnormal invasion and migration. Phosphorylation of CRMP2 at the T514 site in FLSs may present a new therapeutic target for treating inflammatory joint's destruction and arthritic pain in RA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Cytoplasmic polyadenylation element-binding protein 4 (Cpeb4) is an RNA-binding protein that regulates posttranscriptional regulation, such as regulation of messenger RNA stability and translation. In the previous study, we reported that Cpeb4 localizes to nuclear bodies upon induction of osteoclast differentiation by RANKL. However, the mechanisms of the localization of Cpeb4 and osteoclastogenesis by Cpeb4 remain unknown. Here, we show that Cpeb4 localizes to the nuclear bodies by its RNA-binding ability and partially regulates normal splicing during osteoclast differentiation. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis with Phos-tag® revealed that the phosphorylation levels of Cpeb4 were already high in the RAW264.7 cells and were not altered by RANKL treatment. Immunofluorescence showed that exogenous Cpeb4 in HEK293T cells without RANKL stimulation localized to the same foci as shown in RANKL-stimulated RAW264.7 cells. Furthermore, when nuclear export was inhibited by leptomycin B treatment, Cpeb4 accumulated throughout the nucleus. Importantly, RNA recognition motif (RRM) 7 of Cpeb4 was essential for the localization. In contrast, the intrinsically disordered region, RRM1, and zinc finger domain CEBP_ZZ were not necessary for the localization. The mechanistic study showed that Cpeb4 co-localized and interacted with the splicing factors serine/arginine-rich splicing factor 5 (SRSF5) and SRSF6, suggesting that Cpeb4 may be involved in the splicing reaction. RNA-sequencing analysis revealed that the expression of genes related to cell proliferation processes, such as mitotic cell cycle and regulation of cell cycle processes, was elevated in osteoclasts depleted of Cpeb4. Interestingly, the splicing pattern of the inhibitor of DNA binding 2 (Id2) gene, which suppresses osteoclast differentiation, was altered by the depletion of Cpeb4. These results provide new insight into the role of Cpeb4 as a player of normal splicing of Id2 in osteoclast differentiation., (© 2024 Wiley Periodicals LLC.)

Secretory proteins of Plasmodium exhibit differential spatial and functional activity within the host cell nucleus. However, the nuclear localization signals (NLSs) for these proteins remain largely uncharacterized. In this study, we have identified and characterized two NLSs in the circumsporozoite protein of Plasmodium falciparum (Pf-CSP). Both NLSs in the Pf-CSP contain clusters of lysine and arginine residues essential for specific interactions with the conserved tryptophan and asparagine residues of importin-α, facilitating nuclear translocation of Pf-CSP. While the two NLSs of Pf-CSP function independently and are both crucial for nuclear localization, a single NLS of Pf-CSP leads to weak nuclear localization. These findings shed light on the mechanism of nuclear penetrability of secretory proteins of Plasmodium proteins., (© 2024 Federation of European Biochemical Societies.)

The imbalance in the phosphorylation and the dephosphorylation of proteins leads to various diseases. Therefore, in vivo, the functions of protein kinases and protein phosphatases are strictly regulated. Mg 2+ /Mn 2+ -dependent protein phosphatase PPM1M has been implicated in immunity and cancer; however, the regulation mechanism remains unknown. In this study, we show that PPM1M is regulated in different ways by multiple phosphorylation. PPM1M has four Ser/Thr-Pro motifs (Ser27, Ser43, Ser60, and Thr254) that are recognized by proline-directed kinases, and Ser60 was found to be phosphorylated by cyclin-dependent kinase 5 (CDK5) in the cell. The phospho-mimetic mutation of Ser27 and Ser43 in the N-terminal domain suppresses the nuclear localization of PPM1M and promotes its accumulation in the cytoplasm. The phospho-mimetic mutation of Ser60 decreases PPM1M activity; conversely, the phospho-mimetic mutation of Thr254 increases PPM1M activity. These results suggest that the subcellular localization and phosphatase activity of PPM1M are regulated by protein kinases, including CDK5, via phosphorylation at multiple sites. Thus, PPM1M is differentially regulated by proline-directed kinases, including CDK5., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The intricate relationship between Forkhead box O1 (FOXO1), a well-established tumor suppressor, and breast cancer (BC) remains partially elucidated. This study aims to investigate the mechanistic role of FOXO1 nuclear localization in the context of BC., Methods: In vitro experiments employed BC cell lines MCF-7 and MDA-MB-175 treated with LOM612, a small molecule activator of FOXO nuclear-cytoplasmic shuttling, and selinexor, an exportin 1 inhibitor. Nuclear accumulation of FOXO1, its interaction with β-catenin, and expressions of key proteins like V-Myc avian myelocytomatosis viral oncogene homolog (c-Myc), cyclin D1 and apoptosis markers were assessed. In vivo, the effects of LOM612 and selinexor were studied using MCF-7 cell-derived xenografts (CDX)., Results: Treatment with LOM612 exhibited a significant enhancement in nuclear accumulation of FOXO1 within BC cells. This effect coincided with suppressed migratory behavior and heightened apoptosis susceptibility in these cells. Mechanistically, LOM612 orchestrated FOXO1 to compete with transcription factors (TCF) for binding to β-catenin in the nucleus, leading to reduced c-Myc and cyclin D1 expressions, along with elevated levels of apoptosis-related proteins. Similar trends were observed in CDX models, where LOM612 effectively suppressed tumor growth, increased FOXO1 nuclear localization, and downregulated c-Myc and cyclin D1 expressions. Importantly, selinexor synergistically reinforced the therapeutic effects of LOM612 both in vitro and in vivo., Conclusions: Collectively, this study underscores the potential of combining LOM612 and selinexor as an efficacious anti-BC strategy. The underlying mechanism involves FOXO1's nuclear translocation, which disrupts TCF-β-catenin interactions, thus indirectly inhibiting the Wnt/β-catenin signaling pathway., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Hepatic ischemia-reperfusion injury (IRI) typically manifests during subtotal hepatectomy and inflicts substantial damage to liver function in the perioperative period. Although the central role of cGAS-STING-mediated immune inflammation in hepatocyte damage during hepatic IRI is acknowledged, the precise regulatory mechanisms remain elusive. The current study aims to elucidate how Sirt3 inhibition activates the cGAS-STING pathway and exacerbates hepatocyte damage in hepatic IRI. We established both in vivo and in vitro models by creating hepatic IRI mice model and subjecting AML-12 hepatocyte cell lines to oxygen-glucose deprivation/reperfusion (OGD/R). Hepatic IRI compromised liver and mitochondrial function while elevating cytosolic mitochondrial DNA (mtDNA) levels in hepatocytes. Additionally, both in vivo hepatic IRI and in vitro OGD/R induced increased phosphorylation and activation of cGAS, STING, and IRF3, accompanied by heightened levels of pro-inflammatory factors, including TNF-α, IL-1β, and type I interferon (IFN-β). Importantly, knockdown of cGAS or STING through siRNA effectively attenuated hepatic IRI-induced inflammation and ameliorated liver function in both experimental settings, underscoring the dynamic involvement of the cGAS-STING pathway in hepatic IRI-induced inflammation. Furthermore, we observed a significant reduction in Sirt3 expression following hepatic IRI, both in vivo and in vitro. Then we generated Sirt3-deficient mice and applied Sirt3 knockdown in AML-12 hepatocytes. Notably, Sirt3 deficiency led to increased phosphorylation and activation of cGAS, STING, and IRF3, coupled with elevated TNF-α, IL-1β, and IFN-β levels in both in vivo and in vitro conditions. Moreover, upon silencing various downstream targets of Sirt3, such as transcription factors Sp1, Pu1, and p65, we observed that specifically knocking down p65 in AML-12 hepatocytes reduced cGAS mRNA levels. Co-immunoprecipitation assays confirmed a direct interaction between Sirt3 and p65. The absence of Sirt3 significantly increased nuclear translocation of p65 in mice, whereas Sirt3 knockdown in AML-12 hepatocytes heightened nuclear translocation of p65. ChIP-PCR assays demonstrated that Sirt3 deficiency notably enhanced the binding of p65 to two cGAS promoters, ultimately promoting cGAS transcription. Collectively, our results underscored that inhibition of Sirt3 activates the cGAS-STING pathway to aggravate hepatocyte damage by increasing cytosolic mtDNA and promoting nuclear translocation of p65 to promote cGAS transcription in hepatic IRI. These findings hold promise for potential therapeutic interventions in hepatic IRI by targeting the Sirt3-cGAS-STING axis, offering new avenues for the development of clinical strategies to mitigate liver damage during the perioperative period., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Glioblastoma (GBM) is the most common malignant tumor of the central nervous system. It is an aggressive tumor characterized by rapid proliferation, diffuse tumor morphology, and poor prognosis. Unfortunately, current treatments, such as surgery, radiotherapy, and chemotherapy, are unable to achieve good outcomes. Therefore, there is an urgent need to explore new treatment targets. A detailed mechanistic exploration of the role of the nuclear pore transporter KPNB1 in GBM is lacking. This study demonstrated that KPNB1 regulated GBM progression through a transcription factor YBX1 to promote the expression of post-protrusion membrane protein NLGN3. This regulation was mediated by the deubiquitinating enzyme USP7., Methods: A tissue microarray was used to measure the expression of KPNB1 and USP7 in glioma tissues. The effects of KPNB1 knockdown on the tumorigenic properties of glioma cells were characterized by colony formation assays, Transwell migration assay, EdU proliferation assays, CCK-8 viability assays, and apoptosis analysis using flow cytometry. Transcriptome sequencing identified NLGN3 as a downstream molecule that is regulated by KPNB1. Mass spectrometry and immunoprecipitation were performed to analyze the potential interaction between KPNB1 and YBX1. Moreover, the nuclear translocation of YBX1 was determined with nuclear-cytoplasmic fractionation and immunofluorescence staining, and chromatin immunoprecipitation assays were conducted to study DNA binding with YBX1. Ubiquitination assays were performed to determine the effects of USP7 on KPNB1 stability. The intracranial orthotopic tumor model was used to detect the efficacy in vivo., Results: In this study, we found that the nuclear receptor KPNB1 was highly expressed in GBM and could mediate the nuclear translocation of macromolecules to promote GBM progression. Knockdown of KPNB1 inhibited the progression of GBM, both in vitro and in vivo. In addition, we found that KPNB1 could regulate the downstream expression of Neuroligin-3 (NLGN3) by mediating the nuclear import of transcription factor YBX1, which could bind to the NLGN3 promoter. NLGN3 was necessary and sufficient to promote glioma cell growth. Furthermore, we found that deubiquitinase USP7 played a critical role in stabilizing KPNB1 through deubiquitination. Knockdown of USP7 expression or inhibition of its activity could effectively impair GBM progression. In vivo experiments also demonstrated the promoting effects of USP7, KPNB1, and NLGN3 on GBM progression. Overall, our results suggested that KPNB1 stability was enhanced by USP7-mediated deubiquitination, and the overexpression of KPNB1 could promote GBM progression via the nuclear translocation of YBX1 and the subsequent increase in NLGN3 expression., Conclusion: This study identified a novel and targetable USP7/KPNB1/YBX1/NLGN3 signaling axis in GBM cells., (© 2024. The Author(s).)

Background: Renal cell carcinoma (RCC) is one of the most common malignant tumor worldwide. Metastasis is a leading case of cancer-related deaths of RCC. Circular RNAs (circRNAs), a class of noncoding RNAs, have emerged as important regulators in cancer metastasis. However, the functional effects and regulatory mechanisms of circRNAs on RCC metastasis remain largely unknown., Methods: High-throughput RNA sequencing techniques were performed to analyze the expression profiles of circRNAs and mRNAs in highly and poorly invasive clear cell renal cell carcinoma (ccRCC) cell lines. Functional experiments were performed to unveil the regulatory role of circPPAP2B in the proliferation and metastatic capabilities of ccRCC cells. RNA pulldown, Mass spectrometry analysis, RNA methylation immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), co-immunoprecipitation (CoIP), next-generation RNA-sequencing and double luciferase experiments were employed to clarify the molecular mechanisms by which circPPAP2B promotes ccRCC metastasis., Results: In this study, we describe a newly identified circular RNA called circPPAP2B, which is overexpressed in highly invasive ccRCC cells, as determined through advanced high-throughput RNA sequencing techniques. Furthermore, we observed elevated circPPAP2B in ccRCC tissues, particularly in metastatic ccRCC tissues, and found it to be associated with poor prognosis. Functional experiments unveiled that circPPAP2B actively stimulates the proliferation and metastatic capabilities of ccRCC cells. Mechanistically, circPPAP2B interacts with HNRNPC in a m6A-dependent manner to facilitate HNRNPC nuclear translocation. Subcellular relocalization was dependent upon nondegradable ubiquitination of HNRNPC and stabilization of an HNRNPC/Vimentin/Importin α7 ternary complex. Moreover, we found that circPPAP2B modulates the interaction between HNRNPC and splicing factors, PTBP1 and HNPNPK, and regulates pre-mRNA alternative splicing. Finally, our studies demonstrate that circPPAP2B functions as a miRNA sponge to directly bind to miR-182-5p and increase CYP1B1 expression in ccRCC., Conclusions: Collectively, our study provides comprehensive evidence that circPPAP2B promotes proliferation and metastasis of ccRCC via HNRNPC-dependent alternative splicing and miR-182-5p/CYP1B1 axis and highlights circPPAP2B as a potential therapeutic target for ccRCC intervention., (© 2023. The Author(s).)

Potential genotoxicity and carcinogenicity of carbon nanotubes (CNT), as well as the underlying mechanisms, remains a pressing topic. The study aimed to evaluate and compare the genotoxic effect and mechanisms of DNA damage under exposure to different types of CNT. Immortalized human cell lines of respiratory origin BEAS-2B, A549, MRC5-SV40 were exposed to three types of CNT: MWCNT Taunit-M, pristine and purified SWCNT TUBALL™ at concentrations in the range of 0.0006-200 μg/ml. Data on the CNT content in the workplace air were used to calculate the lower concentration limit. The genotoxic potential of CNTs was investigated at non-cytotoxic concentrations using a DNA comet assay. We explored reactive oxygen species (ROS) formation, direct genetic material damage, and expression of a profibrotic factor TGFB1 as mechanisms related to genotoxicity upon CNT exposure. An increase in the number of unstable DNA regions was observed at a subtoxic concentration of CNT (20 μg/ml), with no genotoxic effects at concentrations corresponding to industrial exposures being found. While the three test articles of CNTs exhibited comparable genotoxic potential, their mechanisms appeared to differ. MWCNTs were found to penetrate the nucleus of respiratory cells, potentially interacting directly with genetic material, as well as to enhance ROS production and TGFB1 gene expression. For A549 and MRC5-SV40, genotoxicity depended mainly on MWCNT concentration, while for BEAS-2B - on ROS production. Mechanisms of SWCNT genotoxicity were not so obvious. Oxidative stress and increased expression of profibrotic factors could not fully explain DNA damage under SWCNT exposure, and other mechanisms might be involved., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background/purpose: Dysregulation of receptor tyrosine kinases is implicated in cancer development. This study aimed to investigate the nuclear translocation of Axl, a membrane protein and receptor tyrosine kinase in cancer malignancy., Materials and Methods: We examined Axl's entry into the cell nucleus and validated it with the nuclear export inhibitor leptomycin. Transfection experiments with mutated nuclear localization signals were conducted to assess the impact of reduced nuclear Axl levels on cancer cell malignancy. Additionally, we evaluated the effects of decreased nuclear Axl on sensitivity to radiation and cisplatin, a chemotherapeutic drug., Results: In the present study, we observed nuclear translocation of Axl in cancer cells. Reducing nuclear Axl levels led to a decrease in cancer cell malignancy. This nuclear translocation was further validated using a nuclear export inhibitor, leptomycin. Additionally, transfection experiments with mutated nuclear localization signals confirmed the functional significance of Axl's nuclear localization. Notably, decreased nuclear Axl levels also increased the sensitivity of cancer cells to radiation and cisplatin treatment., Conclusion: This study suggests that Axl's nuclear translocation plays a significant role in cancer malignancy. Targeting Axl's nuclear localization could offer a potential strategy to inhibit cancer progression and improve the efficacy of radiation and chemotherapy treatments., Competing Interests: The authors have no conflicts of interest relevant to this article., (© 2023 Association for Dental Sciences of the Republic of China. Publishing services by Elsevier B.V.)

Objective: To investigate the molecular mechanism of how lactate induces high mobility group box 1 (HMGB1) release. Methods: Gastric cancer HGC-27 cells were divided into the control group and the lactate group (The cells were treated with lactate for 6 h). The level of HMGB1 in the cell culture medium was detected by enzyme-linked immunosorbent assay (ELISA), the localization of HMGB1 was detected using laser confocal microscopy, and the nuclear translocation of HMGB1 was detected using the nucleoplasmic separation assay. The phosphorylation and acetylation levels of HMGB1 were determined by co-immunoprecipitation, and Western blot was used to measure the phosphorylation of Akt and protein kinase C (PKC). HGC-27 cells were first treated with lactate and LY294002, the inhibitor of Akt, and then the phosphorylation of HMGB1 and Akt was analyzed by co-immunoprecipitation and Western blot, respectively. The localization of HMGB1 in cells was detected by laser confocal microscopy. EdU and Transwell assays were used to detect the proliferation and migration abilities of HGC-27 cells, respectively. HGC-27 cells were then injected into the BALB/C null mice for subcutaneous tumor implantation. Mice in the lactate group were intraperitoneally injected with lactate (0.2 g/kg/2 d), while those in the control group were intraperitoneally injected with an equal amount of PBS for 20 consecutive days. ELISA was used to detect the HMGB1 levels in the blood samples taken from the medial canthus vein of the mice, while co-immunoprecipitation and Western blot were used to detect the phosphorylation of HMGB1 and Akt in tumor tissue proteins, respectively. Results: The release levels of HMGB1 in the lactate group were (2 995.00±660.91) pg/ml and (696.33±22.03) pg/ml, after lactate treatment for 6 h and 12 h, respectively, both higher than those in the control group (485.00±105.83) pg/ml ( P <0.001 and P =0.028, respectively). After lactate treatment for 6 h, the relative expression of HMGB1 protein in the cytoplasm of HGC-27 cells was 1.13±0.09, higher than that of the control group (0.83±0.07, P =0.001), while the relative expression of HMGB1 in the nucleus was 0.79±0.06, lower than that of the control group (1.07±0.06, P =0.007). The phosphorylation level of HMGB1 reached 1.41±0.09, which was higher than that of the control group (0.97±0.10, P =0.031). The phosphorylation level of Akt was 11.16±0.06, higher than that of the control group (0.91±0.022, P =0.002). The phosphorylation level and nuclear translocation of HMGB1 induced by lactate decreased obviously after Akt inhibition; the proliferation and migration abilities induced by lactate were also obviously inhibited after Akt inhibition. In vivo, the HMGB1 level in the peripheral blood was (1 280.70±389.66) pg/ml in the lactate group, which was obviously higher than that in the control group (595.11±44.75) pg/ml ( P =0.008), and the phosphorylation levels of HMGB1 and Akt in tumor tissues in the lactate group were obviously enhanced compared with the control group. Conclusion: Lactate induces HMGB1 release through enhancing HMGB1 phosphorylation via the Akt signaling pathway.

Dysregulation of factors in nucleocytoplasmic transport is closely linked to neural developmental diseases. Mutation in Hikeshi, encoding a nonconventional nuclear import carrier of heat shock protein 70 family (HSP70s), leads to inherited leukodystrophy; however, the pathological mechanisms remain elusive. Here, we showed that Hikeshi is essential for central nervous system (CNS) myelination. Deficiency of Hikeshi, which is observed in inherited leukodystrophy patients, resulted in murine oligodendrocyte maturation arrest. Hikeshi is required for nuclear translocation of HSP70s upon differentiation. Nuclear-localized HSP70 promotes murine oligodendrocyte differentiation and remyelination after white matter injury. Mechanistically, HSP70s interacted with SOX10 in the nucleus and protected it from E3 ligase FBXW7-mediated ubiquitination degradation. Importantly, we discovered that Hikeshi-dependent hyperthermia therapy, which induces nuclear import of HSP70s, promoted oligodendrocyte differentiation and remyelination following in vivo demyelinating injury. Overall, these findings demonstrate that Hikeshi-mediated nuclear translocation of HSP70s is essential for myelinogenesis and provide insights into pathological mechanisms of Hikeshi-related leukodystrophy., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Classically associated with gap junction-mediated intercellular communication, connexin43 (Cx43) is increasingly recognized to possess non-canonical biological functions, including gene expression regulation. However, the mechanisms governing the localization and role played by Cx43 in the nucleus, namely in transcription modulation, remain unknown. Using comprehensive and complementary approaches encompassing biochemical assays, super-resolution and immunogold transmission electron microscopy, we demonstrate that Cx43 localizes to the nuclear envelope of different cell types and in cardiac tissue. We show that translocation of Cx43 to the nucleus relies on Importin-β, and that Cx43 significantly impacts the cellular transcriptome, likely by interacting with transcriptional regulators. In vitro patch-clamp recordings from HEK293 and adult primary cardiomyocytes demonstrate that Cx43 forms active channels at the nuclear envelope, providing evidence that Cx43 can participate in nucleocytoplasmic shuttling of small molecules. The accumulation of nuclear Cx43 during myogenic differentiation of cardiomyoblasts is suggested to modulate expression of genes implicated in this process. Altogether, our study provides new evidence for further defining the biological roles of nuclear Cx43, namely in cardiac pathophysiology.

Breast cancer is malignant tumours in women. A large amount of data analysis shows that Metformin has been shown to play a significance role in reducing the risk of breast cancer, but the mechanism remains unclear. The hippo signalling pathway can be involved in the formation, metastasis and recurrence of breast cancer. When YAP/TAZ is activated, cells can overcome contact inhibition and enter a state of uncontrolled proliferation. Therefore, YAP/TAZ is considered a potential therapeutic target for breast cancer. Eighty breast cancer patients, forty cases of triple-negative and forty cases of HER-2+, were included in this study. In vitro and in vivo experiments were used to confirm the YAP/TAZ axis was involved in the effects of metformin on breast cancer. EMT plays an important role in breast cancer, including chemoresistance and tumour metastasis. Our results confirmed that YAP could modulate the activity of EMT, which in turn altered tumour resistance. Therefore, MET can inhibit EMT by reducing the expression of YAP, and finally achieve the therapeutic effect of breast cancer. Our findings support metformin as a novel YAP inhibitor and potentially as a novel breast cancer drug.

Insulin-like growth factor 1 (IGF1) is a peptide growth factor with important functions in multiple aspects of growth, development and metabolism. The biological actions of IGF1 are mediated by the IGF1 receptor (IGF1R), a cell-surface protein that is evolutionarily related to the insulin receptor (InsR). The effects of IGF1 are moderated by a group of binding proteins (IGFBPs) that bind and transport the ligand in the circulation and extracellular fluids. In mechanistic terms, IGF1R function is linked to the MAPK and PI3K signaling pathways. Furthermore, IGF1R has been shown to migrate to cell nucleus, where it functions as a transcriptional activator. The co-localization of IGF1R and MAPK in the nucleus is of major interest as it suggests novel mechanistic paradigms for the IGF1R-MAPK network. Given its potent anti-apoptotic and pro-survival roles, and in view of its almost universal pattern of expression in most types of cancer, IGF1R has emerged as a promising molecular target in oncology. The present review article provides a concise overview of key scientific developments in the research area of IGF and highlights a number of more recent findings, including its nuclear migration and its interaction with oncogenes and tumor suppressors.

Innate immunity is the first line of defense against viral pathogens. Retinoic Acid-Inducible Gene 1 (RIG-I) is a pattern recognition receptor that recognizes virus-associated double-stranded RNA and initiates the interferon responses. Besides signal transduction, RIG-I exerts direct antiviral functions to displace viral proteins on dsRNA via its Helicase activity. Nevertheless, this effector-like activity of RIG-I against herpesviruses remains largely unexplored. It has been previously reported that herpesviruses deamidate RIG-I, resulting in the abolishment of its Helicase activity and signal transduction. In this study, we discovered that RIG-I possessed signaling-independent antiviral activities against murine gamma herpesviruses 68 (γHV68, murid herpesvirus 4). Importantly, a Helicase-dead mutant of RIG-I (K270A) demonstrated comparable inhibition on herpesviruses lytic replication, indicating that this antiviral activity is Helicase-independent. Mechanistically, RIG-I bound the Replication and Transcription Activator (RTA) and diminished its nuclear localization to repress viral transcription. We further demonstrated that RIG-I blocked the nuclear translocation of ORF21 (Thymidine Kinase), ORF75c (vGAT), both of which form a nuclear complex with RTA and RNA polymerase II (Pol II) to facilitate viral transcription. Moreover, RIG-I retained ORF59 (DNA processivity factor) in the cytoplasm to repress viral DNA replication. Altogether, we illuminated a previously unidentified, Helicase-independent effector-like function of RIG-I against γHV68, representing an exquisite host strategy to counteract viral manipulations on innate immune signaling. IMPORTANCE: Retinoic acid-inducible gene I (RIG-I), a member of DExD/H box RNA helicase family, functions as a key pattern recognition receptor (PRR) responsible for the detection of intracellular double-stranded RNA (dsRNA) from virus-infected cells and induction of type I interferon (IFN) responses. Nevertheless, our understanding of the helicase-independent effector-like activity of RIG-I against virus infection, especially herpesvirus infection, remains largely unknown. Herein, by deploying murine gamma herpesviruses 68 (γHV68) as a model system, we demonstrated that RIG-I possessed an interferon and helicase-independent antiviral activity against γHV68 via blocking the nuclear trafficking of viral proteins, which concomitantly repressed the viral early transcription and genome replication thereof. Our work illuminates a previously unidentified antiviral strategy of RIG-I against herpesvirus infection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Nitric oxide synthase (NOS) was initially discovered to participate in the generation of nitric oxide as a defense mechanism against pathogenic infections. In recent years, it has been found that NOS plays a pivotal role in regulating apoptosis and inflammation in mammals. However, the mechanisms underlying NOS-mediated apoptosis in invertebrates remain largely unclear. In this study, we found that the Apostichopus japonicus NOS (AjNOS) expression levels were upregulated by 2.20-fold and 3.46-fold after being challenged with Vibrio splendidus at concentrations of 10 7  CFU mL -1 and 10 8  CFU mL -1 for 12 h compared to the control group, respectively. Under these conditions, the rates of coelomocytes apoptosis were increased from 14.7% to 32.7% and 45.4%, respectively. Treatment with NOS inhibitor (l-NAME) resulted in a reduction of coelomocytes apoptosis rates from 32.6% to 26.5% in V. splendidus (10 7  CFU mL -1 ) groups and from 42.3% to 33.3% in V. splendidus (10 8  CFU mL -1 ) groups, respectively. NOS has been reported to regulate apoptosis through IκBα phosphorylation. Simultaneously, exposure to V. splendidus in conjunction with l-NAME resulted in down-regulation of AjIκBα phosphorylation levels compared to the group infected solely with V. splendidus. Furthermore, immunofluorescence analysis revealed that treatment with l-NAME or interference of AjNOS using siRNA inhibited translocation of AjNF-κB/p65 (RelA) into the nucleus. Previous studies have shown that NF-κB can down-regulate expression levels of Bcl-2 family members, which is an important pathway for regulating apoptosis. In the present study, treatment with l-NAME was found to promote anti-apoptotic AjBcl-2 mRNA increase to 1.41-fold and protein expression increase to 1.86-fold at 12 h post V. splendidus challenge. However, these effects were suppressed by PMA (an NF-κB activator). Overall, our findings demonstrate that AjNOS regulates coelomocytes apoptosis induced by V. splendidus through activation of the AjNF-κB signaling pathway and down-regulation of AjBcl-2 in A. japonicus., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Skin damage caused by exposure to ultraviolet (UV) light has been well documented clinically and histologically. Dopamine receptor D2 (DRD2) possesses various biological functions. However, no study has reported the possible association of DRD2 with UV-induced skin damage. We established DRD2 conditional knockout and UV damage models in this work. The results showed that DRD2 played an important role in the treatment of UV-induced skin damage. The findings of the molecular mechanism study revealed that the internalization of DRD2 after activation can stabilize nuclear factor erythroid 2-related factor 2 (Nrf2). However, the entry of Nrf2 into the nucleus did not increase. We prepared and characterized hyaluronic acid (HA)-coated mesoporous polydopamine (MPDA) nanoparticles (H@P@M). HA facilitated skin epidermal penetration of the nanoparticles to reach the site of inflammation smoothly. Meanwhile, MPDA activated DRD2 internalization to stabilize Nrf2. The release of prunetin inhibited the interaction of Kelch-like ECH-associated protein 1 with Nrf2 and promoted the nuclear translocation of Nrf2. In summary, this study unveiled that in skin inflammation, H@P@M activated and internalized DRD2, which subsequently formed a protein complex with arrestin beta 1-ubiquitin specific protease 8 (USP8)-Nrf2. Deubiquitination was performed to stabilize Nrf2 while promoting the nuclear translocation of Nrf2 to exert anti-inflammatory and antioxidant functions. STATEMENT OF SIGNIFICANCE: Skin is the body's largest physical barrier, always protecting the body from the interference of the external environment. However, excessive exposure to ultraviolet rays in the sun can cause skin inflammation, leading to skin erythema, itching, edema and pain, which can be troublesome in our daily lives. The complex mechanism of skin inflammation caused by ultraviolet radiation has not been fully clarified. In this study, the role of DRD2 in UV-induced skin inflammation was explored, and nano-composite particles HA@Prunetin@MPDA, which act on multiple targets in the anti-inflammatory pathway of DRD2, were developed to maximize the effect of the drug. It provides a new way to treat skin inflammation caused by UV., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Cardiac hypertrophy is initially an adaptive response to physiological and pathological stimuli. Although pathological myocardial hypertrophy is the main cause of morbidity and mortality, our understanding of its mechanism is still weak. NFAT3 (nuclear factor of activated T-cell-3) is a member of the nuclear factor of the activated T cells (NFAT) family. NFAT3 plays a critical role in regulating the expression of cardiac hypertrophy genes by inducing their transcription. Recently, accumulating evidence has indicated that NFAT3 is a potent regulator of the progression of cardiac hypertrophy. This review, for the first time, summarizes the current studies on NFAT3 in cardiac hypertrophy, including the pathophysiological processes and the underlying pathological mechanism, focusing on the nuclear translocation and transcriptional function of NFAT3. This review will provide deep insight into the pathogenesis of cardiac hypertrophy and a theoretical basis for identifying new therapeutic targets in the NFAT3 network., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Background: Thioredoxin 1 (Trx-1) is a small redox protein predominantly localized in the cytoplasm. Its expression is increased in several cancers, including colorectal cancer (CRC). However, the function of Trx-1 translocation to the nucleus in cancer is not clear. In this study, we investigated the role of Trx-1 nuclear translocation in development of CRC. Methods: Expression of Trx-1 and STAT3 was analyzed by Western blot and immunofluorescence. Endogenous interaction of Trx-1, STAT3, and karyopherin α1 in CRC cells was analyzed by co-immunoprecipitation. Trx-1 and pSTAT3 nuclear staining in human CRC tissues was analyzed by immunohistochemistry. A mouse model of AOM/DSS induced colitis-associated cancer (CAC) was utilized to investigate the antitumor effect of PX-12, a Trx-1 inhibitor. A knockin mouse with the Txn1 (KK81-82EE) mutation was generated via CRISPR/Cas9, and CAC was induced in knockin and wild-type mice. Results: Nuclear translocation of Trx-1 was induced by IL-6, and inhibition of this translocation reversed IL-6-induced epithelial-to-mesenchymal transition, invasion and metastasis. Karyopherin α1 was found to specifically mediate IL-6-induced translocation of the Trx-1-pSTAT3 complex into the nucleus. Nuclear Trx-1 expression was closely correlated with lymph node metastasis and distant metastasis in human CRC. In addition, nuclear staining of Trx-1 showed significant positive correlation with nuclear staining of pSTAT3 in human CRC tissues. PX-12, an inhibitor of Trx-1, significantly impaired the activation of STAT3 and suppressed the development of AOM/DSS-induced CAC in mice. Moreover, AOM/DSS-induced nuclear Trx-1 expression was suppressed in Txn1 (KK81-82EE) mice, which inhibited STAT3 activation and cancer progression. Conclusions: These results provide new insights into the mechanisms of STAT3 activation triggered by IL-6 and identify nuclear translocation of Trx-1 as a potential therapeutic target for the treatment of CRC and CAC., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

The N -methyl-D-aspartate (NMDA) glutamate receptors function as plasma membrane ionic channels and take part in very tightly controlled cellular processes activating neurogenic and inflammatory pathways. In particular, the NR1 subunit (new terminology: GluN1) is required for many neuronal and non-neuronal cell functions, including plasticity, survival, and differentiation. Physiologic levels of glutamate agonists and NMDA receptor activation are required for normal neuronal functions such as neuronal development, learning, and memory. When glutamate receptor agonists are present in excess, binding to NMDA receptors produces neuronal/CNS/PNS long-term potentiation, conditions of acute pain, ongoing severe intractable pain, and potential excitotoxicity and pathology. The GluNR1 subunit (116 kD) is necessary as the anchor component directing ion channel heterodimer formation, cellular trafficking, and the nuclear localization that directs functionally specific heterodimer formation, cellular trafficking, and nuclear functions. Emerging studies report the relevance of GluN1 subunit composition and specifically that nuclear GluN1 has major physiologic potential in tissue and/or subnuclear functioning assignments. The shift of the GluN1 subunit from a surface cell membrane to nuclear localization assigns the GluN1 promoter immediate early gene behavior with access to nuclear and potentially nucleolar functions. The present narrative review addresses the nuclear translocation of GluN1, focusing particularly on examples of the role of GluN1 in nociceptive processes.

Objective: Yes-associated protein (YAP) has been widely studied as a mechanotransducer in many cell types, but its function in cartilage is controversial. The aim of this study was to identify the effect of YAP phosphorylation and nuclear translocation on the chondrocyte response to stimuli relevant to osteoarthritis (OA)., Design: Cultured normal human articular chondrocytes from 81 donors were treated with increased osmolarity media as an in vitro model of mechanical stimulation, fibronectin fragments (FN-f) or IL-1β as catabolic stimuli, and IGF-1 as an anabolic stimulus. YAP function was assessed with gene knockdown and inhibition by verteporfin. Nuclear translocation of YAP and its transcriptional co-activator TAZ and site-specific YAP phosphorylation were determined by immunoblotting. Immunohistochemistry and immunofluorescence to detect YAP were performed on normal and OA human cartilage with different degrees of damage., Results: Chondrocyte YAP/TAZ nuclear translocation increased under physiological osmolarity (400 mOsm) and IGF-1 stimulation, which was associated with YAP phosphorylation at Ser128. In contrast, catabolic stimulation decreased the levels of nuclear YAP/TAZ through YAP phosphorylation at Ser127. Following YAP inhibition, anabolic gene expression and transcriptional activity decreased. Additionally, YAP knockdown reduced proteoglycan staining and levels of type II collagen. Total YAP immunostaining was greater in OA cartilage, but YAP was sequestered in the cytosol in cartilage areas with more severe damage., Conclusions: YAP chondrocyte nuclear translocation is regulated by differential phosphorylation in response to anabolic and catabolic stimuli. Decreased nuclear YAP in OA chondrocytes may contribute to reduced anabolic activity and promotion of further cartilage loss., (Copyright © 2023 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Cancer cells are commonly subjected to endoplasmic reticulum (ER) stress. To gain survival advantage, cancer cells exploit the adaptive aspects of the unfolded protein response such as upregulation of the ER luminal chaperone GRP78. The finding that when overexpressed, GRP78 can escape to other cellular compartments to gain new functions regulating homeostasis and tumorigenesis represents a paradigm shift. Here, toward deciphering the mechanisms whereby GRP78 knockdown suppresses EGFR transcription, we find that nuclear GRP78 is prominent in cancer and stressed cells and uncover a nuclear localization signal critical for its translocation and nuclear activity. Furthermore, nuclear GRP78 can regulate expression of genes and pathways, notably those important for cell migration and invasion, by interacting with and inhibiting the activity of the transcriptional repressor ID2. Our study reveals a mechanism for cancer cells to respond to ER stress via transcriptional regulation mediated by nuclear GRP78 to adopt an invasive phenotype.

Dysregulated biological behaviors of trophoblast cells can result in recurrent spontaneous abortion (RSA)-whose underlying etiology still remains insufficient. Autophagy, a conserved intracellular physiological process, is precisely monitored throughout whole pregnancy. Although the exact mechanism or role remains elusive, epigenetic modification has emerged as an important process. Herein, we found that a proportion of RSA patients exhibited higher levels of autophagy in villus tissues compared to controls, accompanied with impaired histone deacetylase (HDAC) expression. The purpose of this study is to explore the connection between HDACs and autophagy in the pathological course of RSA. Mechanistically, using human trophoblast cell models, treatment with HDAC inhibitor (HDACI)-trichostatin A (TSA) can induce autophagy by promoting nuclear translocation and transcriptional activity of the central autophagic regulator transcription factor EB (TFEB). Specifically, overactivated autophagy is involved in the TSA-driven growth inhibition of trophoblast, which can be partially reversed by the autophagy inhibitor chloroquine (CQ) or RNA interference of TFEB. In summary, our results reveal that abnormal acetylation and autophagy levels during early gestation may be associated with RSA and suggest the potential novel molecular target TFEB for RSA treatment.

Viruses, such as Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infect hosts and take advantage of host cellular machinery for genome replication and new virion production. Identifying and elucidating host pathways for viral infection is critical for understanding the development of the viral life cycle and novel therapeutics. The SARS-CoV-2 N protein is critical for viral RNA (vRNA) genome packaging in new virion formation. Using our quantitative Förster energy transfer/Mass spectrometry (qFRET/MS) coupled method and immunofluorescence imaging, we identified three SUMOylation sites of the SARS-CoV-2 N protein. We found that (1) Small Ubiquitin-like modifier (SUMO) modification in Nucleocapsid (N) protein interaction affinity increased, leading to enhanced oligomerization of the N protein; (2) one of the identified SUMOylation sites, K65, is critical for its nuclear translocation. These results suggest that the host human SUMOylation pathway may be critical for N protein functions in viral replication and pathology in vivo. Thus, blocking essential host pathways could provide a novel strategy for future anti-viral therapeutics development, such as for SARS-CoV-2 and other viruses.

There are diverse links between macroautophagy/autophagy pathways and unfolded protein response (UPR) pathways under endoplasmic reticulum (ER) stress conditions to restore ER homeostasis. Phosphorylation of EIF2S1/eIF2α is an important mechanism that can regulate all three UPR pathways through transcriptional and translational reprogramming to maintain cellular homeostasis and overcome cellular stresses. In this study, to investigate the roles of EIF2S1 phosphorylation in regulation of autophagy during ER stress, we used EIF2S1 phosphorylation-deficient ( A/A ) cells in which residue 51 was mutated from serine to alanine. A/A cells exhibited defects in several steps of autophagic processes (such as autophagosome and autolysosome formation) that are regulated by the transcriptional activities of the autophagy master transcription factors TFEB and TFE3 under ER stress conditions. EIF2S1 phosphorylation was required for nuclear translocation of TFEB and TFE3 during ER stress. In addition, EIF2AK3/PERK, PPP3/calcineurin-mediated dephosphorylation of TFEB and TFE3, and YWHA/14-3-3 dissociation were required for their nuclear translocation, but were insufficient to induce their nuclear retention during ER stress. Overexpression of the activated ATF6/ATF6α form, XBP1s, and ATF4 differentially rescued defects of TFEB and TFE3 nuclear translocation in A/A cells during ER stress. Consequently, overexpression of the activated ATF6 or TFEB form more efficiently rescued autophagic defects, although XBP1s and ATF4 also displayed an ability to restore autophagy in A/A cells during ER stress. Our results suggest that EIF2S1 phosphorylation is important for autophagy and UPR pathways, to restore ER homeostasis and reveal how EIF2S1 phosphorylation connects UPR pathways to autophagy. Abbreviations: A/A : EIF2S1 phosphorylation-deficient; ACTB: actin beta; Ad- : adenovirus-; ATF6: activating transcription factor 6; ATZ: SERPINA1/α1-antitrypsin with an E342K (Z) mutation; Baf A1: bafilomycin A 1 ; BSA: bovine serum albumin; CDK4: cyclin dependent kinase 4; CDK6: cyclin dependent kinase 6; CHX: cycloheximide; CLEAR: coordinated lysosomal expression and regulation; Co-IP: coimmunoprecipitation; CTSB: cathepsin B; CTSD: cathepsin D; CTSL: cathepsin L; DAPI: 4',6-diamidino-2-phenylindole dihydrochloride; DMEM: Dulbecco's modified Eagle's medium; DMSO: dimethyl sulfoxide; DTT: dithiothreitol; EBSS: Earle's Balanced Salt Solution; EGFP: enhanced green fluorescent protein; EIF2S1/eIF2α: eukaryotic translation initiation factor 2 subunit alpha; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; ERAD: endoplasmic reticulum-associated degradation; ERN1/IRE1α: endoplasmic reticulum to nucleus signaling 1; FBS: fetal bovine serum; gRNA: guide RNA; GSK3B/GSK3β: glycogen synthase kinase 3 beta; HA: hemagglutinin; Hep : immortalized hepatocyte; IF: immunofluorescence; IRES: internal ribosome entry site; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LMB: leptomycin B; LPS: lipopolysaccharide; MAP1LC3A/B/LC3A/B: microtubule associated protein 1 light chain 3 alpha/beta; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MEFs: mouse embryonic fibroblasts; MFI: mean fluorescence intensity; MTORC1: mechanistic target of rapamycin kinase complex 1; NES: nuclear export signal; NFE2L2/NRF2: NFE2 like bZIP transcription factor 2; OE: overexpression; PBS: phosphate-buffered saline; PLA: proximity ligation assay; PPP3/calcineurin: protein phosphatase 3; PTM: post-translational modification; SDS: sodium dodecyl sulfate; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SEM: standard error of the mean; TEM: transmission electron microscopy; TFE3: transcription factor E3; TFEB: transcription factor EB; TFs: transcription factors; Tg: thapsigargin; Tm: tunicamycin; UPR: unfolded protein response; WB: western blot; WT: wild-type; Xbp1s : spliced Xbp1 ; XPO1/CRM1: exportin 1.

Background: LRRC6 is an assembly factor for dynein arms in the cytoplasm of motile ciliated cells, and when mutated, dynein arm components remained in the cytoplasm. Here, we demonstrate the role of LRRC6 in the active nuclear translocation of FOXJ1, a master regulator for cilia-associated gene transcription., Methods: We generated Lrrc6 knockout (KO) mice, and we investigated the role of LRRC6 on ciliopathy development by using proteomic, transcriptomic, and immunofluorescence analysis. Experiments on mouse basal cell organoids confirmed the biological relevance of our findings., Results: The absence of LRRC6 in multi-ciliated cells hinders the assembly of ODA and IDA components of cilia; in this study, we showed that the overall expression of proteins related to cilia decreased as well. Expression of cilia-related transcripts, specifically ODA and IDA components, dynein axonemal assembly factors, radial spokes, and central apparatus was lower in Lrrc6 KO mice than in wild-type mice. We demonstrated that FOXJ1 was present in the cytoplasm and translocated into the nucleus when LRRC6 was expressed and that this process was blocked by INI-43, an importin α inhibitor., Conclusions: Taken together, these results hinted at the LRRC6 transcriptional regulation of cilia-related genes via the nuclear translocation of FOXJ1. Video Abstract., (© 2023. The Author(s).)

Background: We have previously demonstrated that ginsenoside compound K can attenuate the formation of atherosclerotic lesions. Therefore, ginsenoside compound K has potential for atherosclerosis therapy. How to improve the druggability and enhance the antiatherosclerotic activity of ginsenoside compound K are the core problems in the prevention and treatment of atherosclerosis. CKN is a ginsenoside compound K derivative that was previously reported to have excellent antiatherosclerotic activity in vitro, and we have applied for international patents for it., Methods: Male C57BL/6 ApoE -/- mice were fed a high-fat and high-choline diet to induce atherosclerosis and were subjected to in vivo studies. In vitro, the CCK-8 method was applied to evaluate cytotoxicity in macrophages. Foam cells were utilized, and cellular lipid determination was performed for in vitro studies. The area of atherosclerotic plaque and fatty infiltration of the liver were measured by image analysis. Serum lipid and liver function were determined by a seralyzer. Immunofluorescence and western blot analysis were conducted to explore the alterations in the expression levels of lipid efflux-related proteins. Molecular docking, reporter gene experiments and cellular thermal shift assays were used to verify the interaction between CKN and LXRα., Results: After confirming the therapeutic effects of CKN, molecular docking, reporter gene experiments and cellular thermal shift assays were used to predict and investigate the antiatherosclerotic mechanisms of CKN. CKN exhibited the greatest potency, with a 60.9% and 48.1% reduction in en face atherosclerotic lesions on the thoracic aorta and brachiocephalic trunk, reduced plasma lipid levels and decreased foam cell levels in the vascular plaque content in HHD-fed ApoE -/- mice. Moreover, CKN in the present study may exert its antiatherosclerotic effects through activated ABCA1 by promoting LXRα nuclear translocation and reducing the adverse effects of LXRα activation., Conclusions: Our results revealed that CKN prevented the formation of atherosclerosis in ApoE -/- mice by activating the LXRα pathway., (© 2023. The Author(s).)

Active Notch signalling is elicited through receptor-ligand interactions that result in release of the Notch intracellular domain (NICD), which translocates into the nucleus. NICD activates transcription at target genes, forming a complex with the DNA-binding transcription factor CSL [CBF1/Su(H)/LAG-1] and co-activator Mastermind. However, CSL lacks its own nuclear localisation sequence, and it remains unclear where the tripartite complex is formed. To probe the mechanisms involved, we designed an optogenetic approach to control NICD release (OptIC-Notch) and monitored the subsequent complex formation and target gene activation. Strikingly, we observed that, when uncleaved, OptIC-Notch sequestered CSL in the cytoplasm. Hypothesising that exposure of a juxta membrane ΦWΦP motif is key to sequestration, we masked this motif with a second light-sensitive domain (OptIC-Notch{ω}), which was sufficient to prevent CSL sequestration. Furthermore, NICD produced by light-induced cleavage of OptIC-Notch or OptIC-Notch{ω} chaperoned CSL into the nucleus and induced target gene expression, showing efficient light-controlled activation. Our results demonstrate that exposure of the ΦWΦP motif leads to CSL recruitment and suggest this can occur in the cytoplasm prior to nuclear entry., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)

The pro-inflammatory phenotype of microglia usually induces neuroinflammatory reactions in neuropathic pain. Glycometabolism shift to glycolysis can promote the pro-inflammatory phenotype transition of microglia. The omics data analysis suggest a critical role for Lyn dysregulation in neuropathic pain. The present study aimed at exploring the mechanism of Lyn-mediated glycolysis enhancement of microglia in neuropathic pain. Neuropathic pain model was established by chronic constriction injury (CCI), then pain thresholds and Lyn expression were measured. Lyn inhibitor Bafetinib and siRNA-lyn knockdown were administrated intrathecally to evaluate the effects of Lyn on pain thresholds, glycolysis and interferon regulatory factor 5 (IRF5) nuclear translocation of microglia in vivo and in vitro. ChIP was carried out to observe the binding of transcription factors SP1, PU.1 to glycolytic gene promoters by IRF5 knockdown. Finally, the relationship between glycolysis and pro-inflammatory phenotype transition of microglia was evaluated. CCI led to the upregulation of Lyn expression and glycolysis enhancement in microglia of spinal dorsal horn. Bafetinib or siRNA-lyn knockdown intrathecally alleviated pain hyperalgesia, suppressed glycolysis enhancement and inhibited nuclear translocation of IRF5 in CCI mice. Also, IRF5 promoted the binding of transcription factors SP1, PU.1 to glycolytic gene promoters, and then the enhanced glycolysis facilitated the proliferation and pro-inflammatory phenotype transition of microglia and contributed to neuropathic pain. Lyn-mediated glycolysis enhancement of microglia contributes to neuropathic pain through facilitating IRF5 nuclear translocation in spinal dorsal horn., (© 2023 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Myocardial ischemia-reperfusion injury (MIRI) remains an unsolved puzzle in medical circles. Naringenin (NAR) is a flavonoid with cardioprotective potential. The purpose of this article was to discuss the protective mechanism of NAR in MIRI by regulating macrophage polarization. The MIRI mouse model was established and perfused with NAR before surgery. In the in vitro experiment, macrophages RAW264.7 were treated with lipopolysaccharide to induce M1 polarization after pretreatment with NAR. Rescue experiments were carried out to validate the functions of transcription factor EB (TFEB), the NLR pyrin domain containing 3 (NLRP3) inflammasome, and autophagy in macrophage polarization. NAR reduced histopathological injury and infarction of myocardial tissues in MIRI mice, inhibited M1 polarization and promoted M2 polarization of macrophages, diminished levels of pro-inflammatory factors, and augmented levels of anti-inflammatory factors. NAR facilitated TFEB nuclear translocation and inhibited the NLRP3 inflammasome pathway. Silencing TFEB or Nigericin partly nullified the effect of NAR on macrophage polarization. NAR increased autophagosome formation, autophagy flux, and autophagy level. Autophagy inhibitor 3-methyladenine partly invalidated the inhibition of NAR on the NLRP3 inflammasome pathway. In animal experiments, NAR protected MIRI mice through the TFEB-autophagy-NLRP3 inflammasome pathway. Collectively, NAR inhibited NLRP3 inflammasome activation and facilitated M2 macrophage polarization by stimulating TFEB nuclear translocation, thus protecting against MIRI., (© 2023 Wiley Periodicals LLC.)

Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus belonging to the Arteriviridae family. Currently, the strain has undergone numerous mutations, bringing massive losses to the swine industry worldwide. Despite several studies had been conducted on PRRSV, the molecular mechanisms by which it causes infection remain unclear. Proliferating cell nuclear antigen (PCNA) is a sign of DNA damage and it participates in DNA replication and repair. Therefore, in this study, we investigated the potential role of PCNA in PRRSV infection. We observed that PCNA expression was stable after PRRSV infection in vitro; however, PCNA was translocated from the nucleus to the cytoplasm. Notably, we found the redistribution of PCNA from the nucleus to the cytoplasm in cells transfected with the N protein. PCNA silencing inhibited PRRSV replication and the synthesis of PRRSV shorter subgenomic RNA (sgmRNA) and genomic RNA (gRNA), while PCNA overexpression promoted virus replication and PRRSV shorter sgmRNA and gRNA synthesis. By performing immunoprecipitation and immunofluorescence colocalization, we confirmed that PCNA interacted with replication-related proteins, namely NSP9, NSP12, and N, but not with NSP10 and NSP11. Domain III of the N protein (41-72 aa) interacted with the IDCL domain of PCNA (118-135 aa). Therefore, we propose cytoplasmic transport of PCNA and its subsequent influence on PRRSV RNA synthesis could be a viral strategy for manipulating cell function, thus PCNA is a potential target to prevent and control PRRSV infection., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purpose: Nuclear position is precisely orchestrated during cell division, migration, and maturation of cells and tissues. Here we report a previously unrecognized, programmed movement of the nucleus in rat and mouse cochlear inner hair cells (IHCs) coinciding with the functional maturation of inner hair cells around the onset of hearing., Methods: We measured hair cell length and nuclear position from confocal scans of immunofluorescence-labeled hair cells from whole-mount cochlear preparations throughout post-natal development., Results: In early post-natal days, the IHC experiences a period of sustained growth, during which the nucleus sits at the very basal pole of the cell, far from the apically located mechano-transducing stereocilia, but close to where synapses with primary afferent and efferent neurons are forming. After IHCs reach their final length, the nucleus moves to occupy a new position half-way along the length of the cell. Nuclear translocation begins in the middle turn, completes throughout the cochlea within 2-3 days, and coincides with the emergence of endolymphatic potential, the acquisition of big-conductance potassium channels (BK), and the onset of acoustic hearing. IHCs cultured in-vitro without endolymphatic potential (EP) do not grow, do not express BK, and do not experience nuclear movement. IHCs cultured in high K+ solutions (to simulate EP) grow but do not experience nuclear movement or acquire BK channels., Conclusion: Nuclear migration at the onset of hearing is a key step in the morphological maturation of IHCs. Whether this plays a role in functional maturation remains to be explored., (© 2023. The Author(s).)