The regulation of RGLG2-VWA by Ca2+ ions

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

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 Ca2+ ions are allosteric regulators of RGLG2-VWA, which adopts open state when NCBS1(Novel Calcium ions Binding Site 1) binds Ca2+ ions and switches to closed state after Ca2+ 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 Ca2+ ions in conformational change of VWA domain. In addition, we found that RGLG2closed, corresponding to low affinity, can bind pseudo-ligand, which has never been observed in other VWA domains.

Keywords: Calcium ions binding site; Closed state; Conformational change; Open state; VWA domain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis Proteins* / genetics
  • Arabidopsis Proteins* / metabolism
  • Arabidopsis* / genetics
  • Arabidopsis* / metabolism
  • Ions / metabolism
  • Ligands
  • Molecular Conformation
  • Ubiquitin-Protein Ligases / metabolism

Substances

  • Ubiquitin-Protein Ligases
  • Ligands
  • Ions
  • RGLG2 protein, Arabidopsis
  • Arabidopsis Proteins