Minor sarcoplasmic reticulum membrane components that modulate excitation-contraction coupling in striated muscles.
In striated muscle, activation of contraction is initiated by membrane depolarisation caused by an action potential, which triggers the release of Ca(2+) stored in the sarcoplasmic reticulum by a process called excitation-contraction coupling. Excitation-contraction coupling occurs via a highly sophisticated supramolecular signalling complex at the junction between the sarcoplasmic reticulum and the transverse tubules. It is generally accepted that the core components of the excitation-contraction coupling machinery are the dihydropyridine receptors, ryanodine receptors and calsequestrin, which serve as voltage sensor, Ca(2+) release channel, and Ca(2+) storage protein, respectively. Nevertheless, a number of additional proteins have been shown to be essential both for the structural formation of the machinery involved in excitation-contraction coupling and for its fine tuning. In this review we discuss the functional role of minor sarcoplasmic reticulum protein components. The definition of their roles in excitation-contraction coupling is important in order to understand how mutations in genes involved in Ca(2+) signalling cause neuromuscular disorders.
Treves
Susan
S
Departments of Anesthesia and Biomedicine, Basel University Hospital, Switzerland.
Vukcevic
Mirko
M
Maj
Marcin
M
Thurnheer
Raphael
R
Mosca
Barbara
B
Zorzato
Francesco
F
D000818:Animals; D020013:Calcium Signaling / Q000235:genetics / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D009119:Muscle Contraction / Q000235:genetics / Q000502:physiology*; D009124:Muscle Proteins / Q000235:genetics / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D012519:Sarcoplasmic Reticulum / Q000502:physiology*
D009124:Muscle Proteins