The subcellular and cellular distribution of G protein-coupled receptor kinase 2 in rat brain

• Published in: Neuroscience 1998-12, Vol.87 (3), p.631-637
• Main Authors: Murga, C, Penela, P, Zafra, F, Mayor, F
• Format: Article
• Language: English
• Subjects: Anatomy; Animals; beta-Adrenergic Receptor Kinases; Biological and medical sciences; Brain - cytology; Brain - enzymology; Central nervous system; Cyclic AMP-Dependent Protein Kinases - analysis; desensitization; Fundamental and applied biological sciences. Psychology; G protein-coupled receptor kinase 2; G protein-coupled receptor kinases (GRK); G protein-coupled receptors (GPCR); GTP-Binding Proteins - analysis; Purkinje Cells - enzymology; Pyramidal Cells - enzymology; Rats; Rats, Wistar; subcellular distribution; Subcellular Fractions - chemistry; Synaptosomes - enzymology; Vertebrates: nervous system and sense organs; β-adrenergic receptor kinase ( βARK)
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/S0306-4522(98)00145-6

G protein-coupled receptor kinase 2 has been found to phosphorylate and thus regulate the activity of several G protein-coupled receptors implicated in neuronal signalling pathways. Although this kinase was initially described as a soluble protein, our laboratory has recently found that a significant amount of G protein-coupled receptor kinase 2 is associated with microsomal membranes in liver and different types of cultured cells. In the present report we show that high G protein-coupled receptor kinase 2 specific activity and protein levels are present in microsomal fractions of rat brain homogenates. On the other hand, immunochemical detection using a new antibody raised against the N-terminus of the kinase revealed a specific and widely distributed staining in different areas of the central nervous system, and the association of G protein-coupled receptor kinase 2 with intracellular structures in nervous cells. Our results further suggest that this receptor kinase may be involved in the modulation of G protein-coupled receptor-mediated neurotransmission and that association with microsomal membranes may play a role in G protein-coupled receptor kinase 2 functions in the brain.