D-AKAP2, a Novel Protein Kinase A Anchoring Protein with a Putative RGS Domain

• Published in: Proceedings of the National Academy of Sciences - PNAS 1997-10, Vol.94 (21), p.11184-11189
• Main Authors: Huang, Lily Jun-Shen, Durick, Kyle, Weiner, Joshua A., Chun, Jerold, Taylor, Susan S.
• Format: Article
• Language: English
• Subjects: A Kinase Anchor Proteins; Adaptor Proteins, Signal Transducing; Amino Acid Sequence; Amino acids; Animals; Base Sequence; Binding Sites; Biochemistry; Biological Sciences; Carrier Proteins - biosynthesis; Carrier Proteins - chemistry; Carrier Proteins - metabolism; Cloning, Molecular; Complementary DNA; Conserved Sequence; Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; Cyclic AMP-Dependent Protein Kinase RIIalpha Subunit; Cyclic AMP-Dependent Protein Kinase Type II; Cyclic AMP-Dependent Protein Kinases - biosynthesis; Cyclic AMP-Dependent Protein Kinases - chemistry; Cyclic AMP-Dependent Protein Kinases - metabolism; Deoxyribonucleic acid; DNA; DNA, Complementary; Embryo, Mammalian; Focalism; Gene Library; Goods and services tax; GTPase-Activating Proteins; Macromolecular Substances; Male; Messenger RNA; Mice; Molecular Sequence Data; Organ Specificity; Proteins; Recombinant Proteins - biosynthesis; Recombinant Proteins - chemistry; Recombinant Proteins - metabolism; Resins; RGS proteins; RNA, Messenger - biosynthesis; Sequence Alignment; Sequence Homology, Amino Acid; Substrate Specificity; Testes; Testis - enzymology; Transcription, Genetic
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.94.21.11184

Subcellular localization directed by specific A kinase anchoring proteins (AKAPs) is a mechanism for compartmentalization of cAMP-dependent protein kinase (PKA). Using a two-hybrid screen, a novel AKAP was isolated. Because it interacts with both the type I and type II regulatory subunits, it was defined as a dual specific AKAP or D-AKAP1. Here we report the cloning and characterization of another novel cDNA isolated from that screen. This new member of the D-AKAP family, D-AKAP2, also binds both types of regulatory subunits. A message of 5 kb pairs was detected for D-AKAP2 in all embryonic stages and in all adult tissues tested. In brain, skeletal muscle, kidney, and testis, a 10-kb mRNA was identified. In testis, several small mRNAs were observed. Therefore, D-AKAP2 represents a novel family of proteins. cDNA cloning from a mouse testis library identified the full length D-AKAP2. It is composed of 372 amino acids which includes the R binding fragment, residues 333-372, at its C-terminus. Based on coprecipitation assays, the R binding domain interacts with the N-terminal dimerization domain of RIα and RIIα . A putative RGS domain was identified near the N-terminal region of D-AKAP2. The presence of this domain raises the intriguing possibility that D-AKAP2 may interact with a Gα protein thus providing a link between the signaling machinery at the plasma membrane and the downstream kinase.