Molecular Mechanism of MMP14 Regulating Skeletal Muscle Satellite Cell Differentiation
The aim of this study was to analyze the molecular mechanism by which matrix metal-loproteinase 14(MMP14)regulated the differentiation of skeletal muscle satellite cells.Skeletal muscle satellite cells were isolated from 10 4-week-old C57/BL6 female mice by collagenase diges-tion.First,skeletal muscle satellite cells were induced to differentiate,and then qRT-PCR and Western blot were used to identify the expression changes of MMP14 during the proliferation and differentiation stages of satellite cells.siRNA was applied to inhibit the expression of MMP14 protein,which was divided into experimental group(si-MMP14)and control group(si-NC),with 3 replicates per group:firstly,the cells were induced to differentiate,and the level of cell differentiation between the experimental group and the control group was analyzed by immuno-fluorescence and qRT-PCR;furthermore,proteomic analysis was performed,combined with bioinformatics analysis to identify differentially expressed proteins and screen for key differentially expressed proteins and pathways regulated by MMP14.The results of this study show that:1)The expression level of MMP14 was up-regulated in satellite cell proliferation stage and down-regulated in differentiation stage.Inhibition of MMP14 protein led to the obstruction of myogene-sis,which was manifested by the decrease of myotube fusion index.2)A total of 549 differentially expressed proteins were identified through proteomic analysis,including 66 up-regulated proteins and 483 down-regulated proteins.Differentially expressed proteins were mainly enriched in cell adhesion,fatty acid metabolism,and the AMPK pathway,and were involved in regulating bio-logical processes such as cell fate determination,histone methylation,and chromatin structure.3)MMP14 was found to directly interact with myogenic differentiation related proteins,lipogene-sis related proteins,and heterochromatin structure regulation proteins,through protein interac-tion network analysis.Furthermore,the inhibition of MMP14 resulted in the down-regulation of myogenic differentiation transcription factors(PAX7 and MYOD)as well as H3-K9 methyltrans-ferases(SETDB1 and SUV39H1),while leading to the up-regulation of lipogenic differentiation transcription factors(JUN and C/EBP-β).This study preliminarily analyzed the mechanism by which MMP14 regulates the differentiation of skeletal muscle satellite cells.MMP14 may be involved in the fate determination of satellite cells and the conversion of myogenic and lipogenic differentiation through H3-K9 histone methylation,which occurs before the initiation of satellite cell differentiation.The results of this study provide a theoretical basis for the study of skeletal muscle development.
skeletal muscle satellite cellsdifferentiation of satellite cellsMMP14
万方数据
维普
