Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, 20850, USA.
Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20740, USA.
Biomol NMR Assign. 2024 Dec;18(2):253-256. doi: 10.1007/s12104-024-10196-0. Epub 2024 Aug 31.
Sorcin is a penta-EF hand calcium-binding protein that confers multidrug resistance in cancer cells. It regulates cellular Ca homeostasis by interacting with calcium channels such as Ryanodine receptor 2 and Sarcoplasmic/endoplasmic reticulum Ca-ATPase in a calcium-dependent manner. The crystal structure of the Sorcin has been determined in both calcium-free and calcium-bound states to understand calcium-binding induced conformational change. However, due to its flexibility, most of the N-terminal domain is invisible in these crystal structures. Here we report the H, C, and N backbone resonance assignments of full-length Sorcin in the calcium-free state using solution NMR. The protein secondary structure was predicted based on the assigned backbone chemical shifts using TALOS+ and CSI 3.0. Our backbone resonance assignment of the full-length Sorcin provides a foundation for future NMR spectroscopic studies to uncover the mechanism of Ca sensing by Sorcin.
Sorcin 是一种五 EF 手钙结合蛋白，可赋予癌细胞多药耐药性。它通过与钙通道（如 Ryanodine 受体 2 和肌浆/内质网 Ca-ATPase）相互作用，以依赖于钙的方式调节细胞内 Ca 稳态。已经确定了 Sorcin 的晶体结构，分别处于无钙和结合钙状态，以了解钙结合诱导的构象变化。然而，由于其灵活性，这些晶体结构中大多数 N 端结构域是不可见的。在这里，我们使用溶液 NMR 报告了无钙状态下全长 Sorcin 的 H、C 和 N 骨架共振分配。根据分配的骨架化学位移使用 TALOS+ 和 CSI 3.0 预测了蛋白质二级结构。我们对全长 Sorcin 的骨架共振分配为未来的 NMR 光谱研究提供了基础，以揭示 Sorcin 的 Ca 感应机制。
