Structure of a monomeric variant of rhodopsin kinase at 2.5 Å resolution.
G protein-coupled receptor kinase 1 (GRK1 or rhodopsin kinase) phosphorylates activated rhodopsin and initiates a cascade of events that results in the termination of phototransduction by the receptor. Although GRK1 seems to be a monomer in solution, seven prior crystal structures of GRK1 revealed a similar domain-swapped dimer interface involving the C-terminus of the enzyme. The influence of this interface on the overall conformation of GRK1 is not known. To address this question, the crystalline dimer interface was disrupted with a L166K mutation and the structure of GRK1-L166K was determined in complex with Mg(2+) · ATP to 2.5 Å resolution. GRK1-L166K crystallized in a novel space group as a monomer and exhibited little overall conformational difference from prior structures of GRK1, although the C-terminal domain-swapped region had reorganized owing to loss of the dimer interface.
Life Sciences Institute and the Department of Pharmacology, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216, USA. tesmerjj@umich.edu
John J G
JJ
Tesmer
Mark R
MR
Nance
Puja
P
Singh
Harie
H
Lee
D000818:Animals; D002417:Cattle; D018360:Crystallography, X-Ray; D051606:G-Protein-Coupled Receptor Kinase 1 / Q000737:chemistry* / Q000235:genetics; D008958:Models, Molecular; D009154:Mutation; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D040681:Structural Homology, Protein
D051606:G-Protein-Coupled Receptor Kinase 1