APOBEC2 negatively regulates myoblast differentiation in muscle regeneration. (April 2017)

• Record Type: Journal Article
• Authors: Ohtsubo, Hideaki; Sato, Yusuke; Suzuki, Takahiro; Mizunoya, Wataru; Nakamura, Mako; Tatsumi, Ryuichi; Ikeuchi, Yoshihide
• Is Part Of: International journal of biochemistry & cell biology. Volume 85(2017)
• Page Start: 91
• Page End: 101
• Publication Date: 2017-04
• Subjects: APOBEC apoB mRNA editing enzyme catalytic polypeptide-like -- CTX cardiotoxin -- DMEM Dulbecco's modified Eagle's medium -- FBS fetal bovine serum -- HS horse serum -- MEF2C myocyte enhancer factor 2C -- MyHC myosin heavy chain; APOBEC2 -- Muscle regeneration -- Myoblast differentiation -- Myogenin -- Myotube; Biochemistry -- Periodicals; Cytology -- Periodicals; Biochemistry -- Periodicals; Cell Biology -- Periodicals; Biochimie -- Périodiques; Cytologie -- Périodiques; Biochimie; Cytologie; Biochemistry; Cytology; Ressource Internet (Descripteur de forme); Périodique électronique (Descripteur de forme); Periodicals; 572.05
• DOI: 10.1016/j.biocel.2017.02.005
• Languages: English
• ISSNs: 1357-2725

Abstract

Graphical abstract: Highlights: We examined the effect of APOBEC2 deficiency on myoblast differentiation. APOBEC2 deficiency accelerated myogenic differentiation and fusion of myoblasts. APOBEC2 knockout mice showed early recovery of fiber structures from muscle injury. APOBEC2 is a key negative-regulator of regenerative myoblast-differentiation. Abstract: Recently we found that the deficiency of APOBEC2, a member of apoB mRNA editing enzyme, catalytic polypeptide-like family, leads to a diminished muscle mass and increased myofiber with centrally-located nuclei known as dystrophic phenotypes. APOBEC2 expression is predominant in skeletal and cardiac muscles and elevated exclusively at the early-differentiation phase of wild-type (WT) myoblast cultures; however the physiological significance is still un-known. Here we show that APOBEC2 is a key negative regulator of myoblast differentiation in muscle regeneration. APOBEC2-knockout (A2KO) mice myoblast cultures displayed a normal morphology of primary myotubes along with earlier increase in fusion index and higher expression levels of myosin heavy chain (MyHC), myogenin and its cooperating factor MEF2C than WT myoblasts. Similar response was observable in APOBEC2-knockdown cultures of WT myoblasts that were transfected with the specific siRNA at the differentiation phase (not proliferation phase). Importantly, cardiotoxin-injured A2KO gastrocnemius muscle provided in vivo evidence by showing larger up-regulation of neonatal MyHC and myogenin and hence earlier regeneration of myofiber structures with diminished cross-sectional areas and minimal Feret diameters. Therefore, the findings highlight a promising role for APOBEC2 in normal progression of regenerative myogenesis at the early-differentiation phase upon muscle injury.