Light-induced translocation of Drosophila visual Arrestin2 depends on Rac2

TitleLight-induced translocation of Drosophila visual Arrestin2 depends on Rac2
Publication TypeJournal Article
Year of Publication2010
AuthorsElsaesser R, Kalra D, Li R, Montell C
JournalProc Natl Acad Sci U S A
Volume107
Pagination4740-5
Date Published03/2010
ISSN1091-6490
KeywordsAnimals, Arrestins, Blotting, Western, Drosophila melanogaster, Drosophila Proteins, Eye Proteins, Immunohistochemistry, Light, Microscopy, Confocal, Microscopy, Electron, Transmission, Mutation, Photoreceptor Cells, Invertebrate, Protein Transport, rac GTP-Binding Proteins, Rhodopsin, Vision, Ocular
Abstract

Photoreceptor cells are remarkable in their ability to adjust their sensitivity to light over a wide range of intensities. Rapid termination of the photoresponse is achieved in part by shuttling proteins in and out of the light-transducing compartment of the photoreceptor cells. One protein that undergoes light-dependent translocation is the rhodopsin regulatory protein arrestin. However, the mechanisms coupling rhodopsin to arrestin movement are poorly understood. Here we show that light-dependent shuttling of the major arrestin in Drosophila photoreceptor cells, Arrestin2 (Arr2), occurs independently of known elements of the phototransduction cascade. Disruptions of the trimeric G protein, phospholipase Cbeta, the TRP channel, or the Na(+)/Ca(2+) exchanger did not influence Arr2 localization. Rather, we found that loss of the small GTPase Rac2 severely impaired Arr2 movement and prolonged the termination of the photoresponse. Our findings demonstrate that light-induced translocation of Arr2 occurs through a noncanonical rhodopsin/Rac2 pathway, which is distinct from the classical phototransduction cascade.

DOI10.1073/pnas.0906386107
Alternate JournalProc. Natl. Acad. Sci. U.S.A.
PubMed ID20176938
PubMed Central IDPMC2842041
Grant ListEY010852 / EY / NEI NIH HHS / United States