Molecular cloning, chromosomal localization of human peripheral-type benzodiazepine receptor and PKA regulatory subunit type 1A (PRKAR1A)-associated protein PAP7, and studies in PRKAR1A mutant cells and tissues.
A mouse protein that interacts with the peripheral-type benzodiazepine receptor (PBR) and cAMP-dependent protein kinase A (PKA) regulatory subunit RIalpha (PRKAR1A), named PBR and PKA-associated protein 7 (PAP7), was identified and shown to be involved in hormone-induced steroid biosynthesis. We report the identification of the human PAP7 gene, its expression pattern, genomic structure, and chromosomal mapping to 1q32-1q41. Human PAP7 is a 60-kDa protein highly homologous to the rodent protein. PAP7 is widely present in human tissues and highly expressed in seminal vesicles, pituitary, thyroid, pancreas, renal cortex, enteric epithelium, muscles, myocardium and in steroidogenic tissues, including the gonads and adrenal cortex. These tissues are also targets of Carney complex (CNC), a multiple neoplasia syndrome caused by germline inactivating PRKAR1A mutations (PRKAR1A-mut) and associated with primary pigmented nodular adrenocortical disease (PPNAD) and increased steroid synthesis. PAP7 and PRKAR1A expression were studied in PPNAD and in lymphoblasts from patients bearing PRKAR1A-mut. Like PRKAR1A, PAP7 was decreased in CNC lymphocytes and PPNAD nodules, but not in the surrounding cortex. These studies showed that, like in the mouse, human PAP7 is highly expressed in steroidogenic tissues, where it follows the pattern of PRKAR1A expression, suggesting that it participates in PRKAR1A-mediated tumorigenesis and hypercortisolism.
Liu
Jun
J
Division of Hormone Research, Department of Cell Biology, Georgetown University Medical Center, Washington, DC 20057, USA. papadopv@georgetown.edu).
Matyakhina
Ludmila
L
Han
Zeqiu
Z
Sandrini
Fabiano
F
Bei
Thalia
T
Stratakis
Constantine A
CA
Papadopoulos
Vassilios
V
D048868:Adaptor Proteins, Signal Transducing; D000303:Adrenal Cortex Diseases / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002784:Cholesterol / Q000378:metabolism; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D008565:Membrane Proteins; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D012333:RNA, Messenger / Q000096:biosynthesis; D011963:Receptors, GABA-A / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D013256:Steroids / Q000096:biosynthesis; D013737:Testis / Q000378:metabolism; D014018:Tissue Distribution
C449459:ACBD3 protein, human; C486730:Acbd3 protein, mouse; D048868:Adaptor Proteins, Signal Transducing; D054756:Cyclic AMP-Dependent Protein Kinase RIalpha Subunit; D008565:Membrane Proteins; C517834:PRKAR1A protein, human; C517835:Prkar1a protein, mouse; D012333:RNA, Messenger; D011963:Receptors, GABA-A; D013256:Steroids; D002784:Cholesterol; D017868:Cyclic AMP-Dependent Protein Kinases