D-AKAP2, a novel protein kinase A anchoring protein with a putative RGS domain.
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 RIalpha and RIIalpha. 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 Galpha protein thus providing a link between the signaling machinery at the plasma membrane and the downstream kinase.
Huang
L J
LJ
Howard Hughes Medical Institute, Department of Chemistry and Biochemistry, School of Medicine, University of California at San Diego, La Jolla, CA 92093-0654, USA.
Durick
K
K
Weiner
J A
JA
Chun
J
J
Taylor
S S
SS
D054758:A Kinase Anchor Proteins; D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D003001:Cloning, Molecular; D017124:Conserved Sequence; D054754:Cyclic AMP-Dependent Protein Kinase RIIalpha Subunit; D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D018076:DNA, Complementary; D004622:Embryo, Mammalian; D020690:GTPase-Activating Proteins; D015723:Gene Library; D046911:Macromolecular Substances; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009928:Organ Specificity; D011506:Proteins; D012333:RNA, Messenger / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D013737:Testis / Q000201:enzymology; D014158:Transcription, Genetic
D054758:A Kinase Anchor Proteins; D048868:Adaptor Proteins, Signal Transducing; C108772:Akap10 protein, mouse; D002352:Carrier Proteins; D054754:Cyclic AMP-Dependent Protein Kinase RIIalpha Subunit; D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; D018076:DNA, Complementary; D020690:GTPase-Activating Proteins; D046911:Macromolecular Substances; C517835:Prkar1a protein, mouse; C517821:Prkar2a protein, mouse; D011506:Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D054746:Cyclic AMP-Dependent Protein Kinase Type II; D017868:Cyclic AMP-Dependent Protein Kinases