The skeletal muscle ryanodine receptor of malignant hyperthermia-susceptible (MHS) pigs contains a mutation at residue 615 that is highly correlated with various abnormalities in the regulation of sarcoplasmic reticulum (SR) Ca2+ channel activity. In isolated SR membranes the Arg615 to Cys615 ryanodine receptor mutation is now shown to be directly responsible for an altered tryptic peptide map, due to the elimination of the Arg615 cleavage site. Furthermore, trypsin treatment released 86-99 kDa ryanodine receptor fragments encompassing residue 615 from the SR membranes. We conclude that the 86-99 kDa domain containing residue 615 is near the cytoplasmic surface of the ryanodine receptor and likely near important Ca2+ channel regulatory sites.
Bibliographical noteFunding Information:
.I~~k/,trll~l~T~he a/uthco~rs rwrirshc ,tro/ h.uñk : Dr. Clivc Sl;myhtcr 01 the Howard Huphss Mcdicul loslitutc. University or TL’XIS South-wcstcrn Medical Center, Ibr protein-suqucnciii~ cxpcrtisc. This work was supported by pr;lnts rrom 111~M’u scular Dystrophy Association ol’Amcric;i ;II~ the Niltiunill Pork Producers COUIIC~(lIo J.R.M. und C.F.L.). NIH GM 31382 (to C.F.L.). ;mrl by the University or.Minnc-sotil Agricultural Experiment Stiltion (C.F,L. und W.E,R,), K.P.C. is UII Invcstiyutor ol’ The Ho\vurd Hughes Mcdicul Institute.
- Calcium release channel
- Malignant hyperthermia
- Ryanodine receptor
- Sarcoplasmic reticulum