unc-68 encodes a ryanodine receptor ortholog that is expressed in body-wall muscle cells and is required for normal body tension and locomotion; unc-68 mutants are flaccid, sluggish, and resistant to ryanodine, but have normal muscle ultrastructure; UNC-68 is dispensable for excitation-contraction coupling itself, but may amplify its calcium signals; the unc-68/kra-1(kh30) mutation is an S1444N substitution at a putative protein kinase C phosphorylation site; UNC-68 reduced unc-103(sy557)-induced spicule protraction by one half; unc-68 is orthologous to the human genes RYR1 (OMIM:180901, mutated in malignant hyperthermia and central core disease), RYR2 (OMIM:180902, mutated in stress-induced polymorphic ventricular tachycardia), and RYR3 (OMIM:180903).
Predicted to enable calcium ion binding activity and ryanodine-sensitive calcium-release channel activity. Involved in locomotion; positive regulation of programmed cell death; and protein localization to organelle. Located in I band and sarcoplasmic reticulum. Expressed in body wall musculature; intestine; neurons; and non-striated muscle. Used to study congenital myopathy 1A and malignant hyperthermia. Human ortholog(s) of this gene implicated in several diseases, including catecholaminergic polymorphic ventricular tachycardia 1; intracranial vasospasm; and muscle tissue disease (multiple). Is an ortholog of human RYR1 (ryanodine receptor 1); RYR2 (ryanodine receptor 2); and RYR3 (ryanodine receptor 3).