The SOCS box protein STOPS is required for phototransduction through its effects on phospholipase C

TitleThe SOCS box protein STOPS is required for phototransduction through its effects on phospholipase C
Publication TypeJournal Article
Year of Publication2008
AuthorsWang T, Wang X, Xie Q, Montell C
JournalNeuron
Volume57
Pagination56-68
Date Published2008 Jan 10
ISSN0896-6273
KeywordsAnimals, Animals, Genetically Modified, Antiporters, Drosophila melanogaster, Drosophila Proteins, Electroretinography, Gene Expression Regulation, GTP Phosphohydrolases, Hot Temperature, Membrane Potentials, Microtubule-Associated Proteins, Mutation, Phospholipase C beta, Photic Stimulation, Photoreceptor Cells, Photoreceptor Cells, Invertebrate, Protein Structure, Tertiary, Sequence Alignment, Suppressor of Cytokine Signaling Proteins, Type C Phospholipases, Vision, Ocular
Abstract

Phosphoinositide-specific phospholipase C (PLC) isozymes play roles in a diversity of processes including Drosophila phototransduction. In fly photoreceptor cells, the PLCbeta encoded by norpA is critical for activation of TRP channels. Here, we describe a PLCbeta regulator, STOPS, which encodes a SOCS box protein. Mutation of stops resulted in a reduced concentration of NORPA and a defect in stopping signaling following cessation of the light stimulus. NORPA has been proposed to have dual roles as a PLC- and GTPase-activating protein (GAP). We found that the slow termination resulting from expressing low levels of wild-type NORPA was suppressed by addition of normal amounts of an altered NORPA, which had wild-type GAP activity, but no PLC activity. STOPS is the first protein identified that specifically regulates PLCbeta protein concentration. Moreover, this work demonstrates that a PLCbeta derivative that does not promote TRP channel activation, still contributes to signaling in vivo.

DOI10.1016/j.neuron.2007.11.020
Alternate JournalNeuron
PubMed ID18184564
PubMed Central IDPMC2253723
Grant ListEY08117 / EY / NEI NIH HHS / United States
EY10852 / EY / NEI NIH HHS / United States
R01 EY008117-19 / EY / NEI NIH HHS / United States
R01 EY010852-14 / EY / NEI NIH HHS / United States