Critical sulfhydryls regulate calcium release from sarcoplasmic reticulum.
Rapid Ca2+ release from the sarcoplasmic reticulum (SR)3 can be triggered by either binding of heavy metals to a sulfhydryl (SH) group or by catalyzing the oxidation of endogenous groups to a disulfide. Ca2+ release has been monitored directly using isolated vesicle preparations or indirectly by monitoring phasic contractions in a skinned fiber preparation. SH oxidation triggered by addition of Cu2+/mercaptans, phthalocyanine dyes, reactive disulfides, and various anthraquinones appears to involve a direct interaction with the Ca2+ release protein from the SR. A model is presented in which reversible oxidation and reduction of endogenous SH groups results in the opening and closing of the Ca2+ release channel from the SR.
Abramson
J J
JJ
Physics Department, Portland State University, Oregon 97207.
Salama
G
G
D000818:Animals; D002118:Calcium / Q000502:physiology*; D008962:Models, Theoretical; D009132:Muscles / Q000502:physiology; D015388:Organelles / Q000502:physiology; D012519:Sarcoplasmic Reticulum / Q000502:physiology*; D013438:Sulfhydryl Compounds / Q000378:metabolism
D013438:Sulfhydryl Compounds; D002118:Calcium