title: KLF15 regulates slow myosin heavy chain expression through NFATc1 in C2C12 myotubes.
abstract: A comprehensive understanding of genetic and environmental factors that control skeletal muscle fiber type specification and transformation is essential not only in sports science, but also in myopathy and metabolic disorders. Krüppel-like factors (KLFs) are a subfamily of the zinc-finger class of transcription factors, which are involved in the development, homeostasis, and pathology of cardiovascular systems. Compared to cardiac and smooth muscles, the role of KLFs in skeletal muscle is much less understood. In this study, the endogenous expression of KLF15 was analyzed in differentiating C2C12 muscle cells and mouse skeletal muscle. Our data indicated that Klf15 was upregulated during myogenic differentiation and higher levels of Klf15 mRNA were detected in mouse slow, oxidative soleus muscle (SL) compared to that in fast, glycolytic tibialis anterior muscle (TA), indicating that KLF15 may play a role in myogenesis or myofiber typing. Additional studies revealed that KLF15 regulated the expression of MHC-β/slow rather than muscle cell differentiation. Gene silencing, overexpression, and luciferase reporter assay showed that KLF15 regulated MHC-β/slow by binding to Nfatc1 promoter, inducing its activity, therefore mediating calcineurin/NFAT signaling. Our study contributed to the current knowledge on KLFs in skeletal muscle, and it indicated a need for further intensive studies on the redundant and divergent functions of KLFs.
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Fu
authors.initials: F
authors.lastname: Feng
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Wei
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Weijun
authors.initials: W
authors.lastname: Pang
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Gongshe
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Animal Science, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: yaoyao3153@aliyun.com.
authors.forename: Qingwu W
authors.initials: QW
authors.lastname: Shen
mesh_terms: D000818:Animals; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D051741:Kruppel-Like Transcription Factors; D051379:Mice; D018485:Muscle Fibers, Skeletal / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D018995:Myosin Heavy Chains / Q000235:genetics* / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D004268:DNA-Binding Proteins; C467418:Klf15 protein, mouse; D051741:Kruppel-Like Transcription Factors; D050778:NFATC Transcription Factors; C494005:Nfatc1 protein, mouse; D012333:RNA, Messenger; D014157:Transcription Factors; D018995:Myosin Heavy Chains
keywords: C2C12 myotubes; KLF15; Myosin heavy chain; NFAT