Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
Structure. 2012 Jul 3;20(7):1201-11. doi: 10.1016/j.str.2012.04.015. Epub 2012 Jun 14.
Ryanodine Receptors (RyRs) are huge Ca²⁺ release channels in the endoplasmic reticulum membrane and form targets for phosphorylation and disease mutations. We present crystal structures of a domain in three RyR isoforms, containing the Ser2843 (RyR1) and Ser2808/Ser2814 (RyR2) phosphorylation sites. The RyR1 domain is the target for 11 disease mutations. Several of these are clustered near the phosphorylation sites, suggesting that phosphorylation and disease mutations may affect the same interface. The L2867G mutation causes a drastic thermal destabilization and aggregation at room temperature. Crystal structures for other disease mutants show that they affect surface properties and intradomain salt bridges. In vitro phosphorylation experiments show that up to five residues in one long loop of RyR2 can be phosphorylated by PKA or CaMKII. Docking into cryo-electron microscopy maps suggests a putative location in the clamp region, implying that mutations and phosphorylation may affect the allosteric motions within this area.
兰尼碱受体（Ryanodine Receptors，RyRs）是内质网膜上的巨大钙离子释放通道，并且是磷酸化和疾病突变的作用靶点。我们呈现了三种 RyR 亚型中一个结构域的晶体结构，该结构域包含 Ser2843（RyR1）和 Ser2808/Ser2814（RyR2）磷酸化位点。RyR1 结构域是 11 种疾病突变的靶点。其中一些突变集中在磷酸化位点附近，这表明磷酸化和疾病突变可能影响相同的界面。L2867G 突变会导致在室温下剧烈的热不稳定性和聚集。其他疾病突变体的晶体结构表明，它们会影响表面特性和结构域内盐桥。体外磷酸化实验表明，RyR2 的一个长环中多达五个残基可以被 PKA 或 CaMKII 磷酸化。对接至冷冻电镜图谱提示了一个位于夹钳区域的假定位置，这意味着突变和磷酸化可能会影响该区域内的变构运动。
