Separate promoters in the human A1 adenosine receptor gene direct the synthesis of distinct messenger RNAs that regulate receptor abundance

H Ren and GL Stiles

Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA.

There are two types of transcripts for the human A1, adenosine receptor. They are expressed in a tissue-specific manner in human tissues and contain distinct exons. Previously, it had appeared that the two transcripts may have occurred through alternative splicing. The transcript beta has two upstream AUG codons, which in transiently transfected COS-7 cells leads to a reduced level of receptor expression. When genomic sequence including sequences 5' to transcriptional start site, exon 1A, intron 1A, exon 1B, intron 1B, exon 2, and coding sequence was inserted into an expression vector (pCMV5/huA1), the resulting transcripts had the same overall structure as the transcripts present in human tissues. Primer extension and 5' rapid amplification of cDNA ends of mRNA from transfected cells revealed the transcription start sites for these two transcripts occurred in what previously had been termed introns. These results were confirmed with similar analysis of mRNA derived from human tissues. Two nonconsensus putative TATA boxes (TTAAGA and TTTAAA) are located upstream of the transcription start sites for transcripts alpha and beta. When the TATA boxes and their flanking sequences were fused to a firefly luciferase gene containing promoterless vector, both demonstrated strong promoter activity in Chinese hamster ovary cells. Promoter A directs the synthesis of transcript alpha, and promoter B directs the synthesis of transcript beta. Promoter A contains a series of AGG elements between the putative TATA box and the transcription start, which accounts for a major portion of the promoter activity based on deletion and mutation analysis. In general, promoter A is more active than promoter B in transfected cells. The nonconsensus TATA box in promoter B plays a more important role in promoter activity than the TATA box in promoter A. The human A1 adenosine receptor gene appears to use two separate promoters to direct synthesis of distinct transcripts, which can then regulate the relative abundance of A1 adenosine receptor in tissues. We have redefined the human A1 adenosine receptor gene structure based on these new data.

Volume 48, Issue 6, pp. 975-980, 12/01/1995
Copyright © 1995 by American Society for Pharmacology and Experimental Therapeutics

This article has been cited by other articles:

				S. C. Pingle, S. Jajoo, D. Mukherjea, L. F. Sniderhan, K. A. Jhaveri, A. Marcuzzi, L. P. Rybak, S. B. Maggirwar, and V. Ramkumar Activation of the Adenosine A1 Receptor Inhibits HIV-1 Tat-Induced Apoptosis by Reducing Nuclear Factor-{kappa}B Activation and Inducible Nitric-Oxide Synthase Mol. Pharmacol., October 1, 2007; 72(4): 856 - 867. [Abstract] [Full Text] [PDF]

				S. C. Pingle, S. Mishra, A. Marcuzzi, S. G. Bhat, Y. Sekino, L. P. Rybak, and V. Ramkumar Osmotic Diuretics Induce Adenosine A1 Receptor Expression and Protect Renal Proximal Tubular Epithelial Cells against Cisplatin-mediated Apoptosis J. Biol. Chem., October 8, 2004; 279(41): 43157 - 43167. [Abstract] [Full Text] [PDF]

				L. Yip, H. C. H. Leung, and Y. N. Kwok Role of Adenosine A1 Receptor in the Regulation of Gastrin Release J. Pharmacol. Exp. Ther., August 1, 2004; 310(2): 477 - 487. [Abstract] [Full Text] [PDF]

				S. Tsutsui, J. Schnermann, F. Noorbakhsh, S. Henry, V. W. Yong, B. W. Winston, K. Warren, and C. Power A1 Adenosine Receptor Upregulation and Activation Attenuates Neuroinflammation and Demyelination in a Model of Multiple Sclerosis J. Neurosci., February 11, 2004; 24(6): 1521 - 1529. [Abstract] [Full Text] [PDF]

				H. Pankevych, V. Korkhov, M. Freissmuth, and C. Nanoff Truncation of the A1 Adenosine Receptor Reveals Distinct Roles of the Membrane-proximal Carboxyl Terminus in Receptor Folding and G Protein Coupling J. Biol. Chem., August 8, 2003; 278(32): 30283 - 30293. [Abstract] [Full Text] [PDF]

				B. B. Fredholm, A. P. IJzerman, K. A. Jacobson, K.-N. Klotz, and J. Linden International Union of Pharmacology. XXV. Nomenclature and Classification of Adenosine Receptors Pharmacol. Rev., December 1, 2001; 53(4): 527 - 552. [Abstract] [Full Text] [PDF]

				S. A. Rivkees, M. Chen, J. Kulkarni, J. Browne, and Z. Zhao Characterization of the Murine A1 Adenosine Receptor Promoter, Potent Regulation by GATA-4 and Nkx2.5 J. Biol. Chem., May 14, 1999; 274(20): 14204 - 14209. [Abstract] [Full Text] [PDF]

				H. Ren and G. L. Stiles Dexamethasone Stimulates Human A1 Adenosine Receptor (A1AR) Gene Expression through Multiple Regulatory Sites in Promoter B Mol. Pharmacol., February 1, 1999; 55(2): 309 - 316. [Abstract] [Full Text]

				Z. Nie, Y. Mei, M. Ford, L. Rybak, A. Marcuzzi, H. Ren, G. L. Stiles, and V. Ramkumar Oxidative Stress Increases A1 Adenosine Receptor Expression by Activating Nuclear Factor kappa B Mol. Pharmacol., April 1, 1998; 53(4): 663 - 669. [Abstract] [Full Text]

				S. G. Bhat, M. Wilson, and V. Ramkumar Age-dependent reductions in A1 adenosine receptor expression in rat testes Am J Physiol Cell Physiol, April 1, 1998; 274(4): C1057 - C1064. [Abstract] [Full Text] [PDF]

				H. Ren and G. L. Stiles A Single-Stranded DNA Binding Site in the Human A1 Adenosine Receptor Gene Promoter Mol. Pharmacol., January 1, 1998; 53(1): 43 - 51. [Abstract] [Full Text]

				S. Lu, H. H. Loh, and L.-N. Wei Studies of Dual Promoters of Mouse kappa -Opioid Receptor Gene Mol. Pharmacol., September 1, 1997; 52(3): 415 - 420. [Abstract] [Full Text]

				P. Svenningsson and B. B. Fredholm Glucocorticoids Regulate the Expression of Adenosine A1 but not A2A Receptors in Rat Brain J. Pharmacol. Exp. Ther., February 1, 1997; 280(2): 1094 - 1101. [Abstract] [Full Text]

				S.-H. Lee, M. T. Minowa, and M. M. Mouradian Two Distinct Promoters Drive Transcription of the Human D1A Dopamine Receptor Gene J. Biol. Chem., October 11, 1996; 271(41): 25292 - 25299. [Abstract] [Full Text] [PDF]