Cloning and expression of a bovine adenylyl cyclase type VII specific to the retinal pigment epithelium

• Published in: FEBS letters 1996-01, Vol.378 (3), p.245-249
• Main Authors: Völkel, H., Beitz, E., Klumpp, S., Schultz, J.E.
• Format: Article
• Language: English
• Subjects: AC, adenylyl cyclase; Adenylyl cyclase; Adenylyl Cyclases - biosynthesis; Adenylyl Cyclases - chemistry; Adenylyl Cyclases - genetics; Amino Acid Sequence; Animals; Base Sequence; Blotting, Northern; Cattle; cDNA cloning; Cells, Cultured; Cloning, Molecular; DNA, Complementary; Expression; GTPγS, guanosine-5′-O-(3-thio-triphosphate); Haplorhini; Isoenzymes - chemistry; Isoenzymes - genetics; Kidney - cytology; Molecular Sequence Data; PCR, polymerase chain reaction; Pigment Epithelium of Eye - enzymology; Recombinant Proteins - biosynthesis; Retina; Retina - enzymology; Retinal pigment epithelium; RPE, retinal pigment epithelium; Sequence Homology, Amino Acid
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(95)01470-5

A cDNA of a type 7 adenylyl cyclase isoform was cloned from a bovine retinal pigment epithelium cDNA library using oligonucleotides developed to conserved regions common to mammalian adenylyl cyclases. A 6.7 kb mRNA of very high abundance was uniquely present on Northern blots containing mRNA or total RNA from the pigment epithelium. This transcript was undetectable in all other tissues examined. The cDNA encoded a protein of 1,097 amino acids and exhibited the known doublet of 6 transmembrane-spanning regions in a hydrophobicity plot. The novel member of the type 7 adenylyl cyclase isoform was expressed in COS-1 cells. It was stimulated 10- and 20-fold by 10 μM GTPγS and 100 μM forskolin, respectively. The high expression rate exclusively in the retinal pigment epithelium suggests that this adenylyl cyclase isoform is involved in processes specific to this functionally exceedingly important subretinal cell layer.