Identification and characterization of the human serotonin-4 receptor gene promoter.
The human serotonin-4 (5-HT(4)) receptor gene expression is highly regulated in various tissues. We isolated the human 5-HT(4) receptor gene containing the 5'-flanking region and characterized its promoter. By 5'-RACE (5'-rapid amplification of the cDNA ends) and inverse PCR, multiple transcription initiation sites were identified. The most 5' one (assigned to +1) was 5135 bp upstream to the translation start site. The 500-bp 5'-flanking region contained potential binding sites for transcription factor Sp-1, AP-2, AP-4, and GATA. However, this region lacked TATA- and CAAT-boxes. Transient transfection analyses in human choriocarcinoma T3M-3 (5-HT(4) receptor-positive) and HepG2 (5-HT(4) receptor-negative) cells revealed that the region (-210 to -105) is necessary for the basic and cell-type specific 5-HT(4) receptor gene expression. In addition, untranslated exon 1 contained negative (+112 to +182) as well as positive (+1 to +111) modulators, indicating that exon 1 plays a regulatory role in the 5-HT(4) receptor gene expression.
Hiroi
T
T
Radioisotope Research Institute, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan.
Hayashi-Kobayashi
N
N
Nagumo
S
S
Ino
M
M
Okawa
Y
Y
Aoba
A
A
Matsui
H
H
D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002822:Choriocarcinoma / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005091:Exons; D015723:Gene Library; D006801:Humans; D007438:Introns; D008156:Luciferases / Q000378:metabolism; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D011985:Receptors, Serotonin / Q000235:genetics*; D044422:Receptors, Serotonin, 5-HT4; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016329:Sp1 Transcription Factor / Q000378:metabolism; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured
D017931:DNA Primers; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D011985:Receptors, Serotonin; D016329:Sp1 Transcription Factor; D050656:Transcription Factor AP-2; D014157:Transcription Factors; C055473:enhancer-binding protein AP-4; D044422:Receptors, Serotonin, 5-HT4; D004247:DNA; D008156:Luciferases