Mechanism of YTHDF2-mediated Degradation of M~6A-containing RNAs

正Methylation at the N6 position of adenosine(m~6A),which is a reversible process with important biological implications,is the most abundant internal modification within protein-coding and long noncoding RNAs in eukaryotes.YT521-B homology domain family(YTHDF)proteins are the readers of m~6A,the binding of which results in the alteration of the     

Sin1-mediated mTOR signaling in cell growth,metabolism and immune response

The mammalian target of rapamycin (mTOR) is an evolutionarily conserved Ser/Thr protein kinase with essential cellular function via processing various extracellular and intracellular inputs. Two distinct multi-protein mTOR complexes (mTORC), mTORC1 and mTORC2, have been identified and well characterized in eukaryotic cells from yeast to human. Sin1, which stands for Sty1/Spc1-interacting protein1, also known as mitogen-activated protein kinase (MAPK) associated protein (MAPKAP)1, is an evolutionarily conserved adaptor protein. Mammalian Sin1 interacts with many cellular proteins, but it has been widely studied as an essential component of mTORC2, and it is crucial not only for the assembly of mTORC2 but also for the regulation of its substrate specificity. In this review, we summarize our current knowledge of the structure and functions of Sin1, focusing specifically on its protein interaction network and its roles in the mTOR pathway that could account for various cellular functions of mTOR in growth, metabolism, immunity and cancer.     

Diet high in branched-chain amino acid promotes PDAC development by USP1-mediated BCAT2 stabilizationOA

BCAT2-mediated branched-chain amino acid(BCAA) catabolism is critical for pancreatic ductal adenocarcinoma(PDAC) development,especially at an early stage.However,whether a high-BCAA diet promotes PDAC development in vivo,and the underlying mechanism of BCAT2 upregulation,remain undefined.Here,we find that a high-BCAA diet promotes pancreatic intraepithelial neoplasia(PanIN)progression in LSL-Kras^{G12 D/+}; Pdx1-Cre(KC) mice.Moreover,we screened with an available deubiquitylase library w...     

CRISPR/Cas9-mediated MSTN gene editing induced mitochondrial alterations in C2C12 myoblast cells

BackgroundMyostatin (MSTN) negatively regulates muscle mass and is a potent regulator of energy metabolism. However, MSTN knockout have affect mitochondrial function. This research assessed the mitochondrial energy metabolism of Mstn −/+ KO cells, and wondered whether the mitochondria biogenesis are affected.ResultsIn this study, we successfully achieved Mstn knockout in skeletal muscle C2C12 cells using a CRISPR/Cas9 system and measured proliferation and differentiation using the Cell-Counting Kit-8 assay and qPCR, respectively. We found that MSTN dysfunction could promote proliferation and differentiation compared with the behaviour of wild-type cells. Moreover, Mstn KO induced an increase in KIF5B expression. The mitochondrial content was significantly increased in Mstn KO C2C12 cells, apparently associated with the increases in PGC-1α, Cox1, Cox2, ND1 and ND2 expression. However, no differences were observed in glucose consumption and lactate production. Interestingly, Mstn KO C2C12 cells showed an increase in IL6 and a decrease in TNF-1α levels.ConclusionThese findings indicate that MSTN regulates mitochondrial biogenesis and metabolism. This gene-editing cells provided favourable evidence for animal breeding and metabolic diseases.How to cite: Wang L, Ding Q, Ma S, et al. CRISPR/Cas9-mediated MSTN gene editing Induced Mitochondrial Alterations in C2C12 myoblast Cells. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.03.009     

Defensin γ-thionin from Capsicum chinense improves butyrate cytotoxicity on human colon adenocarcinoma cell line Caco-2

BackgroundButyrate is a histone deacetylase inhibitor that induces apoptosis and inhibits cell proliferation of colorectal cancer cells. To improve its anticancer activity, butyrate has been evaluated mixed with drugs and different molecules. Plant antimicrobial peptides are attractive anticancer alternative molecules because they show selective cytotoxic activity against different cancer cell lines. In this work, we explore if the plant defensin γ-thionin (Capsicum chinense) can improve butyrate activity on Caco-2 cell line and we also determined the mechanism of death activated.ResultsThe combined treatment of γ-thionin (3.5 µM) and butyrate (50 mM) showed higher cytotoxicity on Caco-2 cells with respect to single treatments. Also, the combined treatment reduced cell proliferation and exhibited a higher rate of apoptosis than single treatments. Combined treatment induced caspases 8 and 9 activation to an extent comparable with that of butyrate while γ-thionin did not activate caspases. Additionally, reactive oxygen species generation preceded the onset of apoptosis, and superoxide anion production was higher in cells treated with the combined treatment.ConclusionsThe γ-thionin from Habanero chili pepper improved the butyrate cytotoxicity on Caco-2 cells. This effect occurred through apoptosis induction associated with reactive oxygen species production. Therefore, the combination of butyrate with cytotoxic antimicrobial peptides could be an attractive strategy for cancer therapy.How to cite: Velázquez-Hernández ME, Ochoa-Zarzosa A, López-Meza JE, Defensin γ-thionin from Capsicum chinense improves butyrate cytotoxicity on human colon adenocarcinoma cell line Caco-2. Electron J Biotechnol 2021;52. https://doi.org/10.1016/j.ejbt.2021.04.009