期刊
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY
卷 294, 期 5, 页码 C1288-C1297出版社
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/ajpcell.00033.2008
关键词
ryanodine receptor; calcium sparks; calcium-induced calcium release; calcium signaling; calcium imaging
资金
- NIAMS NIH HHS [K01 AR051519, K01 AR051519-06, K01 AR-051519-04] Funding Source: Medline
- NINDS NIH HHS [F32 NS044636] Funding Source: Medline
Calmodulin is a ubiquitous Ca2+ binding protein that binds to ryanodine rectors (RyR) and is thought to modulate its activity. Here we evaluated the effects of recombinant calmodulin on the rate of occurrence and spatial properties of Ca2+ sparks as an assay of activation in saponin-permeabilized mouse myofibers. Control myofibers exhibited a time-dependent increase and subsequent decrease in spark frequency. Recombinant wild-type calmodulin prevented the time-dependent appearance of Ca2+ sparks and decreased the derived Ca2+ flux from the sarcoplasmic reticulum during a spark by similar to 37%. A recombinant Ca2+-insensitive form of calmodulin resulted in an instantaneous increase in spark frequency as well as an increase in the derived Ca2+ flux by similar to 24%. Endogenous calmodulin was found to primarily localize to the Z-line. Surprisingly, removal of endogenous calmodulin did not alter the time dependence of Ca2+ spark appearance. These results indicate that calmodulin may not be essential for RyR1-dependent Ca2+ release in adult mammalian skeletal muscle.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据