The adhesion GPCRs CELSR1-3 and LPHN3 engage G proteins via distinct activation mechanisms.

Autor: Huong Bui DL, Roach A, Li J, Bandekar SJ, Orput E, Raghavan R, Araç D, Sando R
Jazyk: angličtina
Zdroj: BioRxiv : the preprint server for biology [bioRxiv] 2023 Apr 03. Date of Electronic Publication: 2023 Apr 03.
DOI: 10.1101/2023.04.02.535287
Abstrakt: Adhesion GPCRs (aGPCRs) are a large GPCR class that direct diverse fundamental biological processes. One prominent mechanism for aGPCR agonism involves autoproteolytic cleavage, which generates an activating, membrane-proximal tethered agonist (TA). How universal this mechanism is for all aGPCRs is unclear. Here, we investigate G protein induction principles of aGPCRs using mammalian LPHN3 and CELSR1-3, members of two aGPCR families conserved from invertebrates to vertebrates. LPHNs and CELSRs mediate fundamental aspects of brain development, yet CELSR signaling mechanisms are unknown. We found that CELSR1 and CELSR3 are cleavage-deficient, while CELSR2 is efficiently cleaved. Despite differential autoproteolysis, CELSR1-3 all engage GαS, and CELSR1 or CELSR3 TA point mutants retain GαS coupling activity. CELSR2 autoproteolysis enhances GαS coupling, yet acute TA exposure alone is insufficient. These studies support that aGPCRs signal via multiple paradigms and provide insights into CELSR biological function.
Databáze: MEDLINE