The RNA-binding Protein HuR Binds to Acetylcholinesterase Transcripts and Regulates Their Expression in Differentiating Skeletal Muscle Cells

摘要: During myogenic differentiation, acetylcholinesterase (AChE) transcript levels are known to increase dramatically. Although this can be attributed in part increased transcriptional activity, posttranscriptional mechanisms have also been implicated the high of AChE mRNA myotubes. In study, we observed that transfection a luciferase reporter construct containing full-length 3'-untranslated region (UTR) resulted significantly higher (5-fold) activity differentiated myotubes versus myoblasts. RNA-electrophoretic mobility shift assays (REMSAs) performed with 3'-UTR probe and AU-rich element revealed intensity RNA-binding protein complexes as differentiation proceeded. Using several complementary approaches including supershift REMSA, mRNA-binding pull-down assays, immunoprecipitation followed by reverse transcription-PCR, found mRNA-stabilizing HuR interacts directly transcripts. Stable overexpression C2C12 cells expression endogenous transcripts well 3'-UTR. vitro stability extracts from these controls slower rate decay. The down-regulation mediated through small interfering RNA further confirmed role regulation levels. Taken together, studies demonstrate regulate posttranscriptionally during differentiation.