Article

Bex1 knock out mice show altered skeletal muscle regeneration.

Department of Anatomy and Neurobiology, School of Medicine, University of Maryland Baltimore, Baltimore, MD 21201, USA.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 12/2007; 363(2):405-10. DOI:10.1016/j.bbrc.2007.08.186 pp.405-10
Source: PubMed

ABSTRACT Bex1 and Calmodulin (CaM) are upregulated during skeletal muscle regeneration. We confirm this finding and demonstrate the novel finding that they interact in a calcium-dependent manner. To study the role of Bex1 and its interaction with CaM in skeletal muscle regeneration, we generated Bex1 knock out (Bex1-KO) mice. These mice appeared to develop normally and are fertile, but displayed a functional deficit in exercise performance compared to wild type (WT) mice. After intramuscular injection of cardiotoxin, which causes extensive and reproducible myotrauma followed by recovery, regenerating muscles of Bex1-KO mice exhibited elevated and prolonged cell proliferation, as well as delayed cell differentiation, compared to WT mice. Thus, our results provide the first evidence that Bex1-KO mice show altered muscle regeneration, and allow us to propose that the interaction of Bex1 with Ca(2+)/CaM may be involved in skeletal muscle regeneration.

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Keywords

Bex1
 
Bex1-KO
 
Bex1-KO mice
 
Bex1-KO mice exhibited
 
calcium-dependent manner
 
causes extensive
 
cell differentiation
 
cell proliferation
 
exercise performance
 
fertile
 
functional deficit
 
intramuscular injection
 
muscle regeneration
 
regenerating muscles
 
reproducible myotrauma
 
skeletal muscle regeneration
 
wild type
 
WT
 
WT mice