title: Bex1 knock out mice show altered skeletal muscle regeneration.
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.
authors: Department of Anatomy and Neurobiology, School of Medicine, University of Maryland Baltimore, Baltimore, MD 21201, USA. jkoo001@umaryland.edu
authors: Jae Hyung
authors: JH
authors: Koo
authors: Mark A
authors: MA
authors: Smiley
authors: Richard M
authors: RM
authors: Lovering
authors: Frank L
authors: FL
authors: Margolis
mesh_terms: 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*
chemical_list: C118512:Bex1 protein, mouse; D009419:Nerve Tissue Proteins