| Structural highlights
Function
[FKB1B_HUMAN] Has the potential to contribute to the immunosuppressive and toxic effects of FK506 and rapamycin. PPIases accelerate the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. [RYR1_RABIT] Calcium channel that mediates the release of Ca(2+) from the sarcoplasmic reticulum into the cytoplasm and thereby plays a key role in triggering muscle contraction following depolarization of T-tubules. Repeated very high-level exercise increases the open probability of the channel and leads to Ca(2+) leaking into the cytoplasm. Can also mediate the release of Ca(2+) from intracellular stores in neurons, and may thereby promote prolonged Ca(2+) signaling in the brain. Required for normal embryonic development of muscle fibers and skeletal muscle. Required for normal heart morphogenesis, skin development and ossification during embryogenesis (By similarity).[1] [2]
Publication Abstract from PubMed
Ryanodine receptors (RyRs) mediate the rapid release of calcium (Ca2+) from intracellular stores into the cytosol, which is essential for numerous cellular functions including excitation-contraction coupling in muscle. Lack of sufficient structural detail has impeded understanding of RyR gating and regulation. Here we report the closed-state structure of the 2.3-megadalton complex of the rabbit skeletal muscle type 1 RyR (RyR1), solved by single-particle electron cryomicroscopy at an overall resolution of 4.8 A. We fitted a polyalanine-level model to all 3,757 ordered residues in each protomer, defining the transmembrane pore in unprecedented detail and placing all cytosolic domains as tertiary folds. The cytosolic assembly is built on an extended alpha-solenoid scaffold connecting key regulatory domains to the pore. The RyR1 pore architecture places it in the six-transmembrane ion channel superfamily. A unique domain inserted between the second and third transmembrane helices interacts intimately with paired EF-hands originating from the alpha-solenoid scaffold, suggesting a mechanism for channel gating by Ca2+.
Structure of a mammalian ryanodine receptor.,Zalk R, Clarke OB, Georges AD, Grassucci RA, Reiken S, Mancia F, Hendrickson WA, Frank J, Marks AR Nature. 2014 Dec 1. doi: 10.1038/nature13950. PMID:25470061[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Dulhunty AF, Laver DR, Gallant EM, Casarotto MG, Pace SM, Curtis S. Activation and inhibition of skeletal RyR channels by a part of the skeletal DHPR II-III loop: effects of DHPR Ser687 and FKBP12. Biophys J. 1999 Jul;77(1):189-203. PMID:10388749 doi:10.1016/S0006-3495(99)76881-5
- ↑ Kakizawa S, Yamazawa T, Chen Y, Ito A, Murayama T, Oyamada H, Kurebayashi N, Sato O, Watanabe M, Mori N, Oguchi K, Sakurai T, Takeshima H, Saito N, Iino M. Nitric oxide-induced calcium release via ryanodine receptors regulates neuronal function. EMBO J. 2011 Oct 28;31(2):417-28. doi: 10.1038/emboj.2011.386. PMID:22036948 doi:10.1038/emboj.2011.386
- ↑ Zalk R, Clarke OB, Georges AD, Grassucci RA, Reiken S, Mancia F, Hendrickson WA, Frank J, Marks AR. Structure of a mammalian ryanodine receptor. Nature. 2014 Dec 1. doi: 10.1038/nature13950. PMID:25470061 doi:http://dx.doi.org/10.1038/nature13950
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