Identification of a dantrolene-binding sequence on the skeletal muscle ryanodine receptor.

Article Details

Citation

Copy to clipboard

Paul-Pletzer K, Yamamoto T, Bhat MB, Ma J, Ikemoto N, Jimenez LS, Morimoto H, Williams PG, Parness J

Identification of a dantrolene-binding sequence on the skeletal muscle ryanodine receptor.

J Biol Chem. 2002 Sep 20;277(38):34918-23. Epub 2002 Jul 11.

PubMed ID

12167662 [ View in PubMed

]

Abstract

Dantrolene is a drug that suppresses intracellular Ca(2+) release from sarcoplasmic reticulum (SR) in skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Although its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca(2+) release channel in SR, as a molecular target for dantrolene using the photoaffinity analog [(3)H]azidodantrolene. Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [(3)H]azidodantrolene, indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1 previously shown to affect RyR1 function in vitro and in vivo were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2s, peptides containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [(3)H]azidodantrolene. A monoclonal anti-RyR1 antibody that recognizes RyR1 and its 1400-amino acid N-terminal fragment recognizes DP1 and DP1-2s in both Western blots and immunoprecipitation assays and specifically inhibits [(3)H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in SR. Our results indicate that synthetic domain peptides can mimic a native, ligand-binding conformation in vitro and that the dantrolene-binding site and the epitope for the monoclonal antibody on RyR1 are equivalent and composed of amino acids 590-609.

DrugBank Data that Cites this Article

Drug Targets

Drug	Target	Kind	Organism	Pharmacological Action	Actions
Dantrolene	Ryanodine receptor 1	Protein	Humans	Yes	Antagonist	Details