Search

The phytochrome-interacting factor (PIF) proteins are part of a subfamily of basic helix–loop–helix (bHLH) transcription factors that integrate with phytochromes (PHYs) and are known to play important roles in adaptive changes in plant architecture. However, the characterization and function of PIFs in potatoes are currently poorly understood. In this study, we identified seven PIF members in potatoes and named them StPIF01-1, StPIF01-2, StPIF03, StPIF06-1, StPIF06-2, StPIF07, and StPIF09 based on their location in potato chromosomes. The chromosomal location, gene structures, physicochemical characteristics, phylogenetic tree, and tissue-specific expression of StPIFs were also analyzed. RT-qPCR analysis revealed that the StPIF3 gene was highly induced by shade and may play a crucial regulatory role in potato responses to shade stress. Also, multiple cis-regulatory elements involved in light response were detected in the promoter of the StPIF genes. Subcellular localization analysis indicated that the StPIF3-encoding protein is mainly localized in the nucleus. Transgenic overexpression of StPIF3 in potatoes increased stem length, chlorophyll accumulation, and enhanced shade-avoidance symptoms, whereas the StPIF3-interfering lines had a lower plant height and more chlorophyll accumulation. These findings enhance our comprehension of StPIF gene roles, potentially advancing potato yield and quality research. This study provides detailed information about StPIFs and identifies the function of StPIF3, which is involved in shade-avoidance syndrome. [ABSTRACT FROM AUTHOR]

Secreted proteins are critical mediators in various biological systems, including the immune system, nervous system, and tumor microenvironment. Understanding profound cellular functional heterogeneity in secretion requires multiplexed secreted protein analysis at the single‐cell level. However, most single‐cell protein secretion analysis technologies rely on bulky, expensive instruments, preventing widespread use. Herein, we proposed using a portable and low‐cost desktop scanner to detect multiplexed proteins secreted from single cells. Gold nanoparticle‐enhanced silver staining and tyramide signal amplification are combined to construct a two‐step amplification for single‐cell secretion assay detection. We used this approach to investigate the heterogeneous immune response of macrophages at the single‐cell level, which revealed that only a minority of cells could secrete 10‐fold more MCP‐1 and TNF‐α than the averaged secretion. The reported platform eliminates bulky equipment for single‐cell secretion analysis, making it affordable for basic and clinical research. [ABSTRACT FROM AUTHOR]

Background: Carbapenem-resistant Enterobacterales (CRE) are a significant threat to worldwide public health, resulting in increased morbidity, death, hospitalization time and healthcare expenses. Here, the genomic and phylogenetic characteristics of a multidrug-resistant Escherichia coli isolate carrying both the new mcr-1.33 variant and blaNDM-5 gene obtained from a urinary tract infection in China are investigated. Methods: Antimicrobial susceptibility of E. coli 779 was evaluated by using the broth microdilution method. Short-read Illumina NovaSeq 6000 and long-read Oxford Nanopore MinION platforms were applied to sequence the bacterial whole genomic DNA and then de novo assembled. The genome sequence was annotated using the NCBI Prokaryotic Genome Annotation Pipeline and further subjected to identify the sequence type (ST), capsular type, and antibiotic resistance genes. BacWGSTdb 2.0 was used to perform the core genome multilocus sequence typing (cgMLST) analysis with other closely related E. coli isolates deposited in the public database. Results: E. coli 779 was resistant to aztreonam, levofloxacin, fosfomycin, cefoxitin, cefepime, cefotaxime, imipenem, meropenem, polymyxin, and tigecycline. The complete genome sequence of E. coli 779 is made up of nine contigs totaling 5,667,876 bp, including one chromosome and eight plasmids. The isolate was assigned to ST101, serotype O-:H31, and phylogroup B1. The colistin resistance gene mcr-1.33 (located in a 242,460 bp IncHI2/IncHI2A plasmid) and the β-lactam resistance gene blaNDM-5 (located in a 46,161 bp IncX3 plasmid) were among the 27 antimicrobial resistance genes discovered. The closest relative of E. coli 779, another ST101 strain (E. coli 443) obtained from a sewage sample in Shandong, China in 2015, differs by only 24 cgMLST alleles. Conclusion: We discovered the first multidrug-resistant ST101 E. coli strain with plasmid-mediated mcr-1.33 variant and blaNDM-5 gene in China. These findings would help us to better understanding the genomic traits, antimicrobial resistance mechanisms and epidemiological aspects of this bacterial pathogen. [ABSTRACT FROM AUTHOR]

Recent advances in single-cell proteomics enable the direct profiling of thousands of proteins from a single mammalian cell. However, due to the bottlenecks in detecting low-abundance secreted proteins and extracellular vesicle (EV) proteins (collectively referred to as the secretome) against a background of high-abundance proteins in serum-containing culture medium, the comprehensive investigation of the secretome at the single-cell level using nanoLC-MS/MS still remains challenging. Herein, we report a novel single-cell secretome profiling (SCSP) method by integrating the metabolic labeling of newly synthesized proteins, click chemistry-based enrichment, and in situ digestion of the labeled secretome in an alkyne-functionalized capillary micro-reactor, followed by nanoLC-MS/MS analysis. By this method, an average of 389 protein groups were quantified from the secretome of single HeLa cells (n = 17), with a total of 752 protein groups confidently identified in the single-cell secretome, which is a significant increase compared to the previously reported targeted analysis limited to dozens of secreted proteins by antibody recognition. These results indicated that our developed SCSP method would provide a powerful tool to gain insights into secretion heterogeneity and intercellular communication at the single-cell level., (© 2024 Wiley‐VCH GmbH.)

Background: Lung metastasis is the primary cause of breast cancer-related mortality. Neutrophil extracellular traps (NETs) are involved in the progression of breast cancer. However, the mechanism of NET formation is not fully understood. This study posits that tumor cell-released autophagosomes (TRAPs) play a crucial role in this process., Methods: TRAPs were isolated from breast cancer cell lines to analyze their impact on NET formation in both human and mouse neutrophils. The study used both in vitro and in vivo models, including Toll-like receptor 4 (TLR4 - / - ) mice and engineered breast cancer cell lines. Immunofluorescence, ELISA, Western blotting, RNA sequencing, and flow cytometry were employed to dissect the signaling pathways leading to NET production and to explore their immunosuppressive effects, particularly focusing on the impact of NETs on T-cell function. The therapeutic potential of targeting TRAP-induced NETs and their immunosuppressive functions was evaluated using DNase I and αPD-L1 antibodies. Clinical relevance was assessed by correlating circulating levels of TRAPs and NETs with lung metastasis in patients with breast cancer., Results: This study showed that TRAPs induced the formation of NETs in both human and mouse neutrophils by using the high mobility group box 1 and activating the TLR4-Myd88-ERK/p38 signaling axis. More importantly, PD-L1 carried by TRAP-induced NETs inhibited T-cell function in vitro and in vivo, thereby contributing to the formation of lung premetastatic niche (PMN) immunosuppression. In contrast, Becn1 KD-4T1 breast tumors with decreased circulating TRAPs in vivo reduced the formation of NETs, which in turn attenuated the immunosuppressive effects in PMN and resulted in a reduction of breast cancer pulmonary metastasis in murine models. Moreover, treatment with αPD-L1 in combination with DNase I that degraded NETs restored T-cell function and significantly reduced tumor metastasis. TRAP levels in the peripheral blood positively correlated with NET levels and lung metastasis in patients with breast cancer., Conclusions: Our results demonstrate a novel role of TRAPs in the formation of PD-L1-decorated NETs, which may provide a new strategy for early detection and treatment of pulmonary metastasis in patients with breast cancer., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Efficacy and long-term success of trabeculectomy largely depends on the postoperative development of a functioning filtering bleb. This study was designed to observe histological changes in filtering blebs after trabeculectomy using in vivo confocal microscopy (IVCM), and to investigate the correlation between morphologic appearance and function of filtering blebs., Methods: A total of 46 glaucoma patients who had received a trabeculectomy unilaterally in the past 1 to 60 months underwent slit-lamp examination, applanation tonometry, and in vivo confocal microscopy. Eyes were classified into 4 groups according to the morphologic appearance of the filtering bleb based on the Kronfled system: type I blebs (8 eyes), type II blebs (14 eyes), type III blebs (16 eyes), and type IV blebs (8 eyes). The IVCM images were analyzed for the number of intraepithelial microcysts, the density of subepithelial connective tissue and the presence of blood vessels., Results: Type II blebs presented with numerous intraepithelial vacuolar microcysts, while several large intraepithelial microcysts were found in type I blebs. Subepithelial connective tissue was widely spaced in type I and II blebs. In contrast, type III and IV blebs showed few or no intraepithelial microcysts, and subepithelial connective tissue was densely distributed. Neovascularization was seen in 83.3% of failed blebs, whereas neovascularization was found in only 16.6% of successful blebs., Conclusion: Different types of blebs reveal various histological characteristics at the cellular level, which appear to be correlated with postoperative filtering function.

The study on the 64 vegetable garden soil samples in the Baiyuan District of Guangzhou City showed that there were significantly positive correlations of soil microbial biomass carbon (Cmic) with soil total N, alkali-hydrolygable N, available K, cation exchange capacity (CEC) and organic matter (OM), of soil microbial biomass nitrogen (Nmic) with soil total N, total P, CEC and OM, of soil basal respiration (SBR) with soil total N, alkali-hydrolygable N, available K, CEC and OM, of AWCD with soil total N and OM, and of Shannon diversity index with soil total N and CEC. Low alkali-hydrolygable N increased Cmic SBR, and metabolic quotient (qCO2), while high alkali-hydrolygable N decreased qCO2. High available P decreased Cmic, Nmic and microbial quotient, and a high ratio of available P to alkali-hydrolygable N was related to the decrease of Cmic, Nmic, Cmic/Nmic and SBR. It was suggested that there were significant correlations between soil microbial ecological characteristics and physico-chemical properties, and excessive available nutrients or inappropriate ratios of alkali-hydrolygable N to available P in soil were harmful to soil microbes.