Activated human Orai1 channel in lipid biolayer may exist as a pentamer.
Biochem Biophys Res Commun
; 733: 150723, 2024 Nov 12.
Article
em En
| MEDLINE
| ID: mdl-39312878
ABSTRACT
The human Orai1 (hOrai1) channel plays a crucial role in extracellular Ca2+ influx and has emerged as an attractive drug target for various diseases. However, the activated structure of the hOrai1 channel assembly within a lipid bilayer remains unknown. In this study, we expressed and purified the hOrai1 channel covalently linked to two SOAR tandems (HOSS). Patch-clamp experiments in whole-cell configuration showed that HOSS is constitutively active. Biochemical characterization confirmed that the purified HOSS channels were successfully incorporated into MSP1E3D1 nanodiscs. Negative staining revealed that the HOSS channels resemble a mushroom, with the body representing the hOrai1 channel and the leg representing the SOAR domain. Surprisingly, 2D analysis of cryo-EM data demonstrated a pentameric assembly of HOSS in a lipid bilayer. Our findings suggest that the hOrai1 channel may assemble into different oligomeric states in response to varying membrane environments.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteína ORAI1
/
Bicamadas Lipídicas
Limite:
Humans
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article