Light intensity-dependent arrestin switching for inactivation of a light-sensitive GPCR, bistable opsin.

ABSTRACT: Inactivation of most light-sensitive G protein-coupled receptor (GPCR) opsins involves arrestin binding to terminate cell responses. In the zebrafish pineal organ, UV sensitive parapinopsin 1 (PP1)-expressing cells exhibit color opponency through photoequilibria between two photo-interconvertible states of PP1. The amount of visible light-sensitive active states (photoproducts) is crucial for generating color opponency, raising questions about how and what arrestins are involved in PP1 inactivation. Here, we found two arrestins, Arr3a and Sagb competitively bind to PP1. Photoresponse analyses of the PP1 cells using gene-knockdown larvae revealed Arr3a-involved quick inactivation was switched to Sagb-involved moderate inactivation depending on increased light intensity. Furthermore, we foun

SUBMITTER: Shen B 

PROVIDER: S-EPMC11803233 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature