Bex1 knock out mice show altered skeletal muscle regeneration.
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.
Koo
Jae Hyung
JH
Department of Anatomy and Neurobiology, School of Medicine, University of Maryland Baltimore, Baltimore, MD 21201, USA. jkoo001@umaryland.edu
Smiley
Mark A
MA
Lovering
Richard M
RM
Margolis
Frank L
FL
D000818:Animals; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D018763:Muscle Fatigue / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D012038:Regeneration / Q000502:physiology*
C118512:Bex1 protein, mouse; D009419:Nerve Tissue Proteins