TRPC3 cation channel plays an important role in proliferation and differentiation of skeletal muscle myoblasts.
10.3858/emm.2010.42.9.061
- Author:
Jin Seok WOO
1
;
Chung Hyun CHO
;
Do Han KIM
;
Eun Hui LEE
Author Information
1. Department of Physiology College of Medicine The Catholic University of Korea Seoul 137-701, Korea. EHUI@catholic.ac.kr
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
calcium channel;
dihydropyridine receptor;
MG29;
Orai1;
ryanodine receptor;
TRPC3 cation channel;
TRPC4 cation channel
- MeSH:
Animals;
Calcium/metabolism;
Calcium Channels/metabolism;
Calcium Channels, L-Type/genetics/metabolism;
Cations/metabolism;
*Cell Differentiation;
*Cell Proliferation;
Cells, Cultured;
Excitation Contraction Coupling;
Gene Knockdown Techniques;
Membrane Potentials;
Mice;
Muscle Fibers, Skeletal/*metabolism;
Muscle Proteins/metabolism;
Myoblasts, Skeletal/*metabolism;
Ryanodine Receptor Calcium Release Channel/metabolism;
Sarcoplasmic Reticulum/*physiology;
Synaptophysin/metabolism;
TRPC Cation Channels/genetics/*metabolism;
Transient Receptor Potential Channels/metabolism
- From:Experimental & Molecular Medicine
2010;42(9):614-627
- CountryRepublic of Korea
- Language:English
-
Abstract:
During membrane depolarization associated with skeletal excitation-contraction (EC) coupling, dihydropyridine receptor [DHPR, a L-type Ca2+ channel in the transverse (t)-tubule membrane] undergoes conformational changes that are transmitted to ryanodine receptor 1 [RyR1, an internal Ca2+-release channel in the sarcoplasmic reticulum (SR) membrane] causing Ca2+ release from the SR. Canonical-type transient receptor potential cation channel 3 (TRPC3), an extracellular Ca2+-entry channel in the t-tubule and plasma membrane, is required for full-gain of skeletal EC coupling. To examine additional role(s) for TRPC3 in skeletal muscle other than mediation of EC coupling, in the present study, we created a stable myoblast line with reduced TRPC3 expression and without alpha1SDHPR (MDG/TRPC3 KD myoblast) by knock-down of TRPC3 in alpha1SDHPR-null muscular dysgenic (MDG) myoblasts using retrovirus-delivered small interference RNAs in order to eliminate any DHPR-associated EC coupling-related events. Unlike wild-type or alpha1SDHPR-null MDG myoblasts, MDG/TRPC3 KD myoblasts exhibited dramatic changes in cellular morphology (e.g., unusual expansion of both cell volume and the plasma membrane, and multi-nuclei) and failed to differentiate into myotubes possibly due to increased Ca2+ content in the SR. These results suggest that TRPC3 plays an important role in the maintenance of skeletal muscle myoblasts and myotubes.
