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ABSTRACT: Altered alternative splicing (AS) events are considered pervasive causes that result in the development of carcinogenesis. Herein, we identified reprogrammed expression and splicing profiles of Muscle blind-like protein 1 (MBNL1) transcripts in tumorous tissues compared to those of adjacent normal tissues dissected from individual colorectal cancer (CRC) patients using whole-transcriptome analyses. MBNL1 transcript 8 (MBNL18) containing exons 5 and 7 was majorly generated by cancerous tissues and CRC-derived cell lines compared with those of the normal counterparts. Interplay between the exonic CA-rich element and upregulated SRSF3 facilitated the inclusion of MBNL1 exons 5 and 7, which encode a bipartite nuclear localization signal (NLS) and conformational NLS. Moreover, abundant SRSF3 interfered with the autoregulatory mechanism involved in utilization of MBNL1 exons 5 and 7, resulting in enrichment of the MBNL18 isoform in cultured CRC cell lines. Subsequently, an increase in the MBNL18 isoform drove a shift in the apoptotic chromatin condensation inducer in nucleus 1-S (Acin1-S) isoform to the Acin1-L isoform, leading to diminished DNA fragmentation in cultured CRC cells under oxidative stress. Taken together, SRSF3-MBNL1-Acin1 was demonstrated to constitute an emerging axis which is relevant to proapoptotic signatures and post-transcriptional events of CRC cells.

Background and objective During the occurring and developing of tumor, tumor-educated platelets mRNA profiles were altered. Since platelets are anuclear, the level of mRNAs is probably post-transcriptional regulated by the splicing maturation of pre-mRNA and alternative splicing. Apoptotic chromatin condensation inducer 1 (ACIN1) has been shown to be a component of a splicing-dependent multiprotein exon junction complex (EJC) and was involved in mRNA metabolism associated with splicing. This study analyzed the expression of ACIN1 mRNA in platelets, and explored its potential as a biomarker of lung cancer. Methods 156 patients with lung cancer and 58 healthy controls in Shandong Cancer Hospital were collected. We isolated platelet pellets by low-speed centrifugation and extracted total RNA. The expression of ACIN1 mRNA in platelets was detected by RT-PCR, the results were analyzed statistically. And the relationship between expression of ACIN1 mRNA and clinical factors were also analyzed. Results The expression level of ACIN1 mRNA in platelets of patients with lung cancer was significantly higher than that in platelets of healthy controls (P=0.015). The ROC curve showed that the area under the curve of ACIN1 mRNA for detecting lung cancer were 0.608. The expression of ACIN1 mRNA in platelets of lung cancer has no significant relationship with age, gender, pathological type and metastasis or not (P>0.05). Conclusion ACIN1 mRNA was highly expressed in platelets of lung cancer patients, and the detection of its expression level might have potential clinical value for the diagnosis of lung cancer.

• Differential splicing profiles of MBNL1 and Acin1 gene is noted in CRC tissues or cells. • Autoregulated exclusion of MBNL1 exons is altered with upregulated SRSF3 • MBNL1 isoform differentially modulates CRC-related AS events. • SRSF3 and MBNL1 exerts opposite impact on expression of the Acin1 isoform. • Acin1 isoform exhibits distinct influence on DNA fragmentation in CRC cells. • SRSF3-MBNL11-Acin1 constitutes an emerging circuit involved in apoptosis of CRC cells. Altered alternative splicing (AS) events are considered pervasive causes that result in the development of carcinogenesis. Herein, we identified reprogrammed expression and splicing profiles of Muscle blind-like protein 1 (MBNL1) transcripts in tumorous tissues compared to those of adjacent normal tissues dissected from individual colorectal cancer (CRC) patients using whole-transcriptome analyses. MBNL1 transcript 8 (MBNL1 8) containing exons 5 and 7 was majorly generated by cancerous tissues and CRC-derived cell lines compared with those of the normal counterparts. Interplay between the exonic CA-rich element and upregulated SRSF3 facilitated the inclusion of MBNL1 exons 5 and 7, which encode a bipartite nuclear localization signal (NLS) and conformational NLS. Moreover, abundant SRSF3 interfered with the autoregulatory mechanism involved in utilization of MBNL1 exons 5 and 7, resulting in enrichment of the MBNL1 8 isoform in cultured CRC cell lines. Subsequently, an increase in the MBNL1 8 isoform drove a shift in the apoptotic chromatin condensation inducer in nucleus 1-S (Acin1-S) isoform to the Acin1-L isoform, leading to diminished DNA fragmentation in cultured CRC cells under oxidative stress. Taken together, SRSF3-MBNL1-Acin1 was demonstrated to constitute an emerging axis which is relevant to proapoptotic signatures and post-transcriptional events of CRC cells. [ABSTRACT FROM AUTHOR]

AIM: To observe the expression of Acin1(apoptotic chromatin condensation inducer 1)in congenital cataract mouse retina during development and investigate the differences of retinal apoptosis and the connection of lens and retina development between congenital cataract mouse and normal mouse.METHODS: There were congenital cataract mice(10 female and 5 male)and normal C57BL/6 mice(10 female and 5 male). One male and two female mice were fed in the same cage randomly. The young mice were divided into two groups: congenital cataract group and normal control group. Five young mice were treated each group on 1, 5, 9, 14, 17, 21, 26, 60d. The left eyes were fixed with 4% neutral formalin to detect ACIN1 protein by immunohistochemistry and retinas from right eyes were used to detect the mRNA expression of Acin1.RESULTS: Acin1 had sustained expression in each group. ACIN1 protein gradually expressed from the ganglion cell layer, inner nuclear layer to the outer nuclear layer following retinal development. It mainly expressed on ganglion cell layer and inner nuclear layer, but not neuroblastoma layer. ACIN1 protein positive cells on P1～P14d increased in normal control group, P17d reduced, after P21d positive cells of each layers decreased. The overall trend was similar in congenital cataract group with normal control group, P1～P14d positive cells count was lower than normal control group, P17-P21d positive cells were flat and higher than the normal control group. Compared with the same day of the two groups, the differences except for P17, P26, P60d were significant(PFcataract=295.07, PPFnormal=214.21, PPPAcin1 mRNA trends of two groups were similar with ACIN1 protein. Compared with the same day of the two groups, the difference was significant except for P17, P21, P60d(PFcataract=522.29, PFnormal=472.05, PPPCONCLUSION: Acin1 exist differential expression of time and space in mouse retina during development, congenital cataract crystal developmental disorder may affect the expression of Acin1 and retinal cell apoptosis and development.

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N6-methyladenosine (m6A) plays a critical role in the tumorigenesis of cervical cancer (CC). Here, we aimed to investigate the potential role of methyltransferase-like 3 (METTL3) in CC. Gene expression was determined via real-time quantitative polymerase chain reaction. Cellular functions were detected using colony formation, 5-ethynyl-2'-deoxyuridine (EdU), and Transwell assays. The interactions among METTL3, insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3), and apoptotic chromatin condensation inducer 1 (ACIN1) were confirmed using the MeRIP and RIP assays. An in vivo assay was performed to verify the role of METTL3 in CC development. METTL3 is overexpressed in CC, and therefore, its knockdown inhibits the proliferation and migration of CC cells. Silencing METTL3 inhibits tumor growth in vivo . Moreover, a positive association was observed between METTL3 and ACIN1. METTL3 interacts with IGF2BP3 to promote the mRNA stability of ACIN1, the overexpression of which induces the aggressiveness of CC cells. METTL3 promotes ACIN1 mRNA stability to accelerate CC progression, implying that METTL3 is a promising biomarker in CC.

Apoptotic chromatin condensation inducer in the nucleus (also referred as Acin1) was first characterized as an RNA-binding protein involved in apoptosis. In later reports, Acin1 was identified as an auxiliary component of the exon junction complex (EJC) which is assembled throughout pre-messenger RNA splicing. In this study, results of whole-transcriptome analyses revealed reduced expressions and reprogrammed splicing profiles of Acin1 transcripts throughout development of brown adipose tissues (BATs) that execute non-shivering thermogenesis in small rodents and infants by consuming lipids. Depletion of endogenous Acin1 isoforms led to activation of brown adipogenic signatures in mouse C3H10T1/2 fibroblasts. Nevertheless, overexpressions of the Acin1-L or Acin1-S isoform exerted discriminative influences on brown adipogenesis and reprogramming of the expression of serine/arginine-rich splicing factor 3 (SRSF3) through an alternative splicing-coupled nonsense-mediated decay mechanism in a sequence-specific manner. Moreover, the Acin1-SRSF3 axis constitutes a regulatory pathway that participates in the brown adipocyte-related splicing network. Taken together, the interplay between accessory EJC components and splicing regulators constitutes an emerging mechanism for differentially manipulating the activity of brown adipogenesis via alternative splicing network. • Altered expressions of Acin1 transcripts are noted during brown adipogenesis. • Depletion of Acin1 protein leads to active brown adipogenesis. • Acin1 isoform exerts discriminative impact on BAs-related splicing events. • Acin1 modulates splicing of SRSF3 transcripts via an intronic U-motif mechanism. • Acin1-SRSF3 cascade manipulates BAs-related splicing events. [ABSTRACT FROM AUTHOR]

Apoptotic chromatin condensation inducer in the nucleus (also referred as Acin1) was first characterized as an RNA-binding protein involved in apoptosis. In later reports, Acin1 was identified as an auxiliary component of the exon junction complex (EJC) which is assembled throughout pre-messenger RNA splicing. In this study, results of whole-transcriptome analyses revealed reduced expressions and reprogrammed splicing profiles of Acin1 transcripts throughout development of brown adipose tissues (BATs) that execute non-shivering thermogenesis in small rodents and infants by consuming lipids. Depletion of endogenous Acin1 isoforms led to activation of brown adipogenic signatures in mouse C3H10T1/2 fibroblasts. Nevertheless, overexpressions of the Acin1-L or Acin1-S isoform exerted discriminative influences on brown adipogenesis and reprogramming of the expression of serine/arginine-rich splicing factor 3 (SRSF3) through an alternative splicing-coupled nonsense-mediated decay mechanism in a sequence-specific manner. Moreover, the Acin1-SRSF3 axis constitutes a regulatory pathway that participates in the brown adipocyte-related splicing network. Taken together, the interplay between accessory EJC components and splicing regulators constitutes an emerging mechanism for differentially manipulating the activity of brown adipogenesis via alternative splicing network., Competing Interests: Declaration of competing interest All authors agree and declare that no conflict of interest exists., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: During the occurring and developing of tumor, tumor-educated platelets mRNA profiles were altered. Since platelets are anuclear, the level of mRNAs is probably post-transcriptional regulated by the splicing maturation of pre-mRNA and alternative splicing. Apoptotic chromatin condensation inducer 1 (ACIN1) has been shown to be a component of a splicing-dependent multiprotein exon junction complex (EJC) and was involved in mRNA metabolism associated with splicing. This study analyzed the expression of ACIN1 mRNA in platelets, and explored its potential as a biomarker of lung cancer., Methods: 156 patients with lung cancer and 58 healthy controls in Shandong Cancer Hospital were collected. We isolated platelet pellets by low-speed centrifugation and extracted total RNA. The expression of ACIN1 mRNA in platelets was detected by RT-PCR, the results were analyzed statistically. And the relationship between expression of ACIN1 mRNA and clinical factors were also analyzed., Results: The expression level of ACIN1 mRNA in platelets of patients with lung cancer was significantly higher than that in platelets of healthy controls (P=0.015). The ROC curve showed that the area under the curve of ACIN1 mRNA for detecting lung cancer were 0.608. The expression of ACIN1 mRNA in platelets of lung cancer has no significant relationship with age, gender, pathological type and metastasis or not (P>0.05)., Conclusions: ACIN1 mRNA was highly expressed in platelets of lung cancer patients, and the detection of its expression level might have potential clinical value for the diagnosis of lung cancer.