The Drosophila G-protein-coupled receptor kinase homologue Gprk2 is required for egg morphogenesis.
G protein signaling is a widely utilized form of extracellular communication that is mediated by a family of serpentine receptors containing seven transmembrane domains. In sensory neurons, cardiac muscle and other tissues, G protein-coupled receptors are desensitized through phosphorylation by a family of kinases, the G protein-coupled receptor kinases (GRKs). Desensitization allows a cell to decrease its response to a given signal, in the continued presence of that signal. We have identified a Drosophila mutant, gprk2(6936) that disrupts expression of a putative member of the GRK family, the G protein-coupled receptor kinase 2 gene (Gprk2). This mutation affects Gprk2 gene expression in the ovaries and renders mutant females sterile. The mutant eggs contain defects in several anterior eggshell structures that are produced by specific subsets of migratory follicle cells. In addition, rare eggs that become fertilized display gross defects in embryogenesis. These observations suggest that developmental signals transduced by G protein-coupled receptors are regulated by receptor phosphorylation. Based on the known functions of G protein-coupled receptor kinases, we speculate that receptor desensitization assists cells that are migrating or undergoing shape changes to respond rapidly to changing external signals.
Schneider
L E
LE
University of Vermont, Department of Biology, Burlington 05405, USA.
Spradling
A C
AC
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002451:Cell Compartmentation; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D005260:Female; D054769:G-Protein-Coupled Receptor Kinase 2; D019204:GTP-Binding Proteins / Q000378:metabolism; D015870:Gene Expression; D007247:Infertility, Female; D019476:Insect Proteins; D008969:Molecular Sequence Data; D009024:Morphogenesis; D009154:Mutation; D009866:Oogenesis / Q000235:genetics*; D010063:Ovum / Q000254:growth & development* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014018:Tissue Distribution; D051552:beta-Adrenergic Receptor Kinases
D029721:Drosophila Proteins; D019476:Insect Proteins; D012333:RNA, Messenger; C064196:dpp protein, Drosophila; D017868:Cyclic AMP-Dependent Protein Kinases; D051552:beta-Adrenergic Receptor Kinases; D054769:G-Protein-Coupled Receptor Kinase 2; C496574:Gprk2 protein, Drosophila; D019204:GTP-Binding Proteins