PUBLICATION
Kinase activity-independent regulation of cyclin pathway by GRK2 is essential for zebrafish early development
- Authors
- Jiang, X., Yang, P., and Ma, L.
- ID
- ZDB-PUB-090616-35
- Date
- 2009
- Source
- Proceedings of the National Academy of Sciences of the United States of America 106(25): 10183-10188 (Journal)
- Registered Authors
- Keywords
- cyclin B1, early arrest, embryonic development, G protein-coupled receptor kinase, PTCH1
- MeSH Terms
-
- Animals
- Cattle
- Cell Proliferation
- Cyclin B/metabolism
- Cyclin B1
- Cyclins/metabolism*
- Down-Regulation
- G-Protein-Coupled Receptor Kinase 2/genetics
- G-Protein-Coupled Receptor Kinase 2/metabolism*
- Humans
- Mutation
- Receptors, Cell Surface/metabolism*
- Two-Hybrid System Techniques
- Zebrafish/embryology*
- Zebrafish/metabolism
- PubMed
- 19502428 Full text @ Proc. Natl. Acad. Sci. USA
Citation
Jiang, X., Yang, P., and Ma, L. (2009) Kinase activity-independent regulation of cyclin pathway by GRK2 is essential for zebrafish early development. Proceedings of the National Academy of Sciences of the United States of America. 106(25):10183-10188.
Abstract
G protein-coupled receptor (GPCR) kinases (GRKs) are known as a family of serine/threonine kinases that function as key regulators of GPCRs, as well as other types of receptors. Extensive studies of GRKs at the cellular and organismal levels have led to a consensus that GRK-catalyzed phosphorylation of receptors is the primary mechanism underlying their physiological functions. Here, we report that down-regulation of GRK2 in zebrafish embryos with GRK2 morpholino results in developmental early arrest and, interestingly, that this arrest can be rescued by exogenous expression of a GRK2 kinase-dead mutant, K220R. A physical interaction between GRK2 and cyclin B1 regulator patched homolog 1 (PTCH1), stimulated by Hedgehog (Hh), rather than GRK2-mediated phosphorylation of downstream targets, appears as the underlying mechanism. We identify residues 262-379 as the PTCH1-binding region (BP). Interaction of GRK2, K220R, and BP with PTCH1 reduces the association of PTCH1 with cyclin B1 and disrupts PTCH1-mediated inhibition of cyclin B1 nuclear translocation, whereas the PTCH1-binding deficient GRK2 mutant (Delta312-379) does not. Cell cycle and cell proliferation assays show that overexpressing PTCH1 remarkably inhibited cell growth and this effect could be attenuated by GRK2, K220R, or BP, but not Delta312-379. In vivo studies show that BP, as well as the nuclear-localizing cyclin B1 mutant, is effective in rescuing the early arrest phenotype in GRK2 knockdown embryos, but Delta312-379 is not. Our data thus reveal a novel kinase activity-independent function for GRK and establish a role for GRK2 as a cell-cycle regulator during early embryonic development.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping