Ryanodine receptor 1 (RYR-1) also known as skeletal muscle calcium release channel or skeletal muscle-type ryanodine receptor is a protein found primarily in skeletal muscle. In humans, it is encoded by the RYR1gene.[1][2]
RYR1 functions as a calcium release channel in the sarcoplasmic reticulum, as well as a connection between the sarcoplasmic reticulum and the transverse tubule.[3] RYR1 is associated with the dihydropyridine receptor (L-type calcium channels) within the sarcolemma of the T-tubule, which opens in response to depolarization, and thus effectively means that the RYR1 channel opens in response to depolarization of the cell.
RYR1 plays a signaling role during embryonic skeletal myogenesis. A correlation exists between RYR1-mediated Ca2+ signaling and the expression of multiple molecules involved in key myogenic signaling pathways.[4] Of these, more than 10 differentially expressed genes belong to the Wnt family which are essential for differentiation. This coincides with the observation that without RYR1 present, muscle cells appear in smaller groups, are underdeveloped, and lack organization. Fiber type composition is also affected, with less type 1 muscle fibers when there are decreased amounts of RYR1.[5] These findings demonstrate RYR1 has a non-contractile role during muscle development.
RYR1 is mechanically linked to neuromuscular junctions for the calcium release-calcium induced biological process. While nerve-derived signals are required for acetylcholine receptor cluster distribution, there is evidence to suggest RYR1 activity is an important mediator in the formation and patterning of these receptors during embryological development.[6] The signals from the nerve and RYR1 activity appear to counterbalance each other. When RYR1 is eliminated, the acetylcholine receptor clusters appear in an abnormally narrow pattern, yet without signals from the nerve, the clusters are scattered and broad. Although their direct role is still unknown, RYR1 is required for proper distribution of acetylcholine receptor clusters.
Clinical significance
Mutations in the RYR1 gene are associated with malignant hyperthermia susceptibility, central core disease, minicore myopathy with external ophthalmoplegia and samaritan myopathy, a benign congenital myopathy.[7] Alternatively spliced transcripts encoding different isoforms have been demonstrated.[3]Dantrolene may be the only known drug that is effective during cases of malignant hyperthermia.[citation needed]
↑Fujii J, Otsu K, Zorzato F, de Leon S, Khanna VK, Weiler JE, O'Brien PJ, MacLennan DH (July 1991). "Identification of a mutation in porcine ryanodine receptor associated with malignant hyperthermia". Science. 253 (5018): 448–51. doi:10.1126/science.1862346. PMID1862346.
↑Wu S, Ibarra MC, Malicdan MC, Murayama K, Ichihara Y, Kikuchi H, Nonaka I, Noguchi S, Hayashi YK, Nishino I (June 2006). "Central core disease is due to RYR1 mutations in more than 90% of patients". Brain. 129 (Pt 6): 1470–80. doi:10.1093/brain/awl077. PMID16621918.
↑Willemse H, Theodoratos A, Smith PN, Dulhunty AF (February 2016). "Unexpected dependence of RyR1 splice variant expression in human lower limb muscles on fiber-type composition". Pflügers Archiv. 468 (2): 269–78. doi:10.1007/s00424-015-1738-9. PMID26438192.
↑Gaburjakova M, Gaburjakova J, Reiken S, Huang F, Marx SO, Rosemblit N, Marks AR (May 2001). "FKBP12 binding modulates ryanodine receptor channel gating". The Journal of Biological Chemistry. 276 (20): 16931–5. doi:10.1074/jbc.M100856200. PMID11279144.
↑Hwang SY, Wei J, Westhoff JH, Duncan RS, Ozawa F, Volpe P, Inokuchi K, Koulen P (August 2003). "Differential functional interaction of two Vesl/Homer protein isoforms with ryanodine receptor type 1: a novel mechanism for control of intracellular calcium signaling". Cell Calcium. 34 (2): 177–84. doi:10.1016/S0143-4160(03)00082-4. PMID12810060.
↑ 14.014.114.2Feng W, Tu J, Yang T, Vernon PS, Allen PD, Worley PF, Pessah IN (November 2002). "Homer regulates gain of ryanodine receptor type 1 channel complex". The Journal of Biological Chemistry. 277 (47): 44722–30. doi:10.1074/jbc.M207675200. PMID12223488.
↑Lee JM, Rho SH, Shin DW, Cho C, Park WJ, Eom SH, Ma J, Kim DH (February 2004). "Negatively charged amino acids within the intraluminal loop of ryanodine receptor are involved in the interaction with triadin". The Journal of Biological Chemistry. 279 (8): 6994–7000. doi:10.1074/jbc.M312446200. PMID14638677.
↑Caswell AH, Motoike HK, Fan H, Brandt NR (January 1999). "Location of ryanodine receptor binding site on skeletal muscle triadin". Biochemistry. 38 (1): 90–7. doi:10.1021/bi981306. PMID9890886.
↑Guo W, Campbell KP (April 1995). "Association of triadin with the ryanodine receptor and calsequestrin in the lumen of the sarcoplasmic reticulum". The Journal of Biological Chemistry. 270 (16): 9027–30. doi:10.1074/jbc.270.16.9027. PMID7721813.
↑Groh S, Marty I, Ottolia M, Prestipino G, Chapel A, Villaz M, Ronjat M (April 1999). "Functional interaction of the cytoplasmic domain of triadin with the skeletal ryanodine receptor". The Journal of Biological Chemistry. 274 (18): 12278–83. doi:10.1074/jbc.274.18.12278. PMID10212196.
Further reading
Treves S, Anderson AA, Ducreux S, Divet A, Bleunven C, Grasso C, Paesante S, Zorzato F (October 2005). "Ryanodine receptor 1 mutations, dysregulation of calcium homeostasis and neuromuscular disorders". Neuromuscular Disorders. 15 (9–10): 577–87. doi:10.1016/j.nmd.2005.06.008. PMID16084090.