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BACKGROUND Glycogen synthase kinase 3β (GSK3B, GSK-3β) is a multi-functional protein kinase involved in various cellular processes and its activity elevates after serum deprivation. We have shown that inhibition of GSK-3β activity triggered a profound autophagic response and subsequent necrotic cell death after serum deprivation in prostate cancer cells. In this study, we dissected the mechanisms involved in GSK-3β inhibition-triggered autophagy. METHODS Prostate cancer PC-3 and DU145 cells were used in the study. Multiple GSK-3β specific inhibitors were used including small chemicals TDZD8, Tideglusib, TWS119, and peptide L803-mts. Western blot assay coupled with phospho-specific antibodies were used in detecting signal pathway activation. ATP levels were assessed with ATPLite kit and HPLC methods. Autophagy response was determined by evaluating Microtubule-associated proteins 1A/1B light chain 3B (LC3B) processing and p62 protein stability in Western blot assays. Immunofluorescent microscopy was used to detect LKB1 translocation. RESULTS Inhibition of GSK-3β activity resulted in a significant decline of cellular ATP production, leading to a significant increase of AMP/ATP ratio, a strong trigger of AMP-activated protein kinase (AMPK) activation in prostate cancer PC-3 cells. In parallel with increased LC-3B biosynthesis and p62 protein reduction, the classical sign of autophagy induction, AMPK was activated after inhibition of GSK-3β activity. Further analysis revealed that Liver kinase B1 (LKB1) but not Calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ) is involved in AMPK activation and autophagy induction triggered by GSK-3β inhibition. Meanwhile, GSK-3β inhibition promoted LKB1 translocation from nuclear to cytoplasmic compartment and enhanced LKB1 interaction with its regulatory partners Mouse protein-25 (MO25) and STE20-related adaptor (STRAD). CONCLUSIONS In conclusion, our data suggest that GSK-3β plays an important role in controlling autophagy induction by modulating the activation of LKB1-AMPK pathway after serum deprivation.

The mechanism of alternative pre-mRNA splicing (AS) during preimplantation development is largely unknown. In order to capture the dynamic changes of AS occurring during embryogenesis, we carried out bioinformatics analysis based on scRNA-seq data over the time-course preimplantation development in mouse. We detected numerous previously-unreported differentially expressed genes at specific developmental stages and investigated the nature of AS at both minor and major zygotic genome activation (ZGA). The AS and differential AS atlas over preimplantation development were established. The differentially alternatively spliced genes (DASGs) are likely to be key splicing factors (SFs) during preimplantation development. We also demonstrated that there is a regulatory cascade of AS events in which some key SFs are regulated by differentially AS of their own gene transcripts. Moreover, 212 isoform switches (ISs) during preimplantation development were detected, which may be critical for decoding the mechanism of early embryogenesis. Importantly, we uncovered that zygotic AS activation (ZASA) is in conformity with ZGA and revealed that AS is coupled with transcription during preimplantation development. Our results may provide a deeper insight into the regulation of early embryogenesis.

Alternative splicing (AS) is pervasive in human multi-exon genes and is a major contributor to expansion of the transcriptome and proteome diversity. The accurate recognition of alternative splice sites is regulated by information contained in networks of protein-protein and protein-RNA interactions. However, the mechanisms leading to splice site selection are not fully understood. Although numerous databases have been built to describe AS, molecular interaction databases associated with AS have only recently emerged. In this study, we present a new database, MiasDB, that provides a description of molecular interactions associated with human AS events. This database covers 938 interactions between human splicing factors, RNA elements, transcription factors, kinases and modified histones for 173 human AS events. Every entry includes the interaction partners, interaction type, experimental methods, AS type, tissue specificity or disease-relevant information, a simple description of the functionally tested interaction in the AS event and references. The database can be queried easily using a web server (http://47.88.84.236/Miasdb). We display some interaction figures for several genes. With this database, users can view the regulation network describing AS events for 12 given genes.

The objective of this study is to evaluate the remission rate and describe the current use of medication in a large cohort of rheumatoid arthritis (RA) patients under routine clinical care in China. RA patients were recruited from 40 large teaching hospitals nationwide in China. Data regarding RA disease activity, medication treatment, and adverse events were recorded using a standardized clinical data questionnaire. RA remission was evaluated by the 28 Joint Disease Activity Score DAS28-ESR Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), and American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria. A total of 1945 patients with RA were included in the study. The proportions of patients who fulfilled the DAS28-ESR, CDAI, SDAI, and ACR/EULAR remission criteria were 10.90%, 6.17%, 5.04% , and 1.75%, respectively. Most patients had taken at least one disease-modifying anti-rheumatic drug (DMARD), and the most common prescriptions included leflunomide (LEF) and methotrexate (MTX). DMARD combined with botanics were the most common and dominant strategy for RA management (29.16%). Overall, 433 patients (22.27%) had at least one adverse event. Gastrointestinal adverse events (41.27%) were the most frequently reported events. The incidence of side effects in patients using biologics DMARDs (bDMARDs) was significantly lower than that in those taking MTX, LEF, or sulfasalazine (SSZ). The remission rate of RA disease activity, as assessed in Chinese clinical practice, was very low. Adverse effects of the medicine occurred in approximately one in five RA patients, with bDMARDs were demonstrated to be the medication with the lowest side effects.