钙离子对RGLG2-VWA的调节作用。

The regulation of RGLG2-VWA by Ca ions.

作者信息

Zhang MeiLing, Zhang JiaXiang, Liang Yan, Tian ShiCheng, Xie ShuYang, Zhou Tong, Wang Qin

机构信息

Department of Biochemistry and Molecular Biology, Binzhou Medical University, YanTai, ShanDong 264003, PR China.

出版信息

Biochim Biophys Acta Proteins Proteom. 2024 Jan 1;1872(1):140966. doi: 10.1016/j.bbapap.2023.140966. Epub 2023 Sep 19.

DOI:10.1016/j.bbapap.2023.140966

PMID:37734561

Abstract

RGLG2, an E3 ubiquitin ligase in Arabidopsis thaliana, affects hormone signaling and participates in drought regulation. Here, we determined two crystal structures of RGLG2 VWA domain, representing two conformations, open and closed, respectively. The two structures reveal that Ca ions are allosteric regulators of RGLG2-VWA, which adopts open state when NCBS1(Novel Calcium ions Binding Site 1) binds Ca ions and switches to closed state after Ca ions are removed. This mechanism of allosteric regulation is identical to RGLG1-VWA, but distinct from integrin α and β VWA domains. Therefore, our data provide a backdrop for understanding the role of the Ca ions in conformational change of VWA domain. In addition, we found that RGLG2, corresponding to low affinity, can bind pseudo-ligand, which has never been observed in other VWA domains.

摘要

RGLG2是拟南芥中的一种E3泛素连接酶，影响激素信号传导并参与干旱调节。在此，我们确定了RGLG2 VWA结构域的两种晶体结构，分别代表开放和闭合两种构象。这两种结构表明，钙离子是RGLG2-VWA的变构调节剂，当NCBS1（新型钙离子结合位点1）结合钙离子时，RGLG2-VWA处于开放状态，去除钙离子后则转变为闭合状态。这种变构调节机制与RGLG1-VWA相同，但与整合素α和β VWA结构域不同。因此，我们的数据为理解钙离子在VWA结构域构象变化中的作用提供了背景。此外，我们发现，亲和力较低的RGLG2能够结合假配体，这在其他VWA结构域中从未观察到。