Promoter regions of the human X-linked housekeeping genes PRPS1 and PRPS2 encoding phosphoribosylpyrophosphate synthetase subunit I and II isoforms.
The 5' regions of the human phosphoribosylpyrophosphate synthetase subunit I and II genes (PRPS1 and PRPS2, respectively) were isolated and sequenced. A comparison of the nucleotide sequences between human and rat PRPS1 genes revealed that the sequences around the transcription initiation sites were conserved over 56 nucleotides, and that a TATA-like sequence, a CCAAT box and three putative Sp1 binding sites were present at almost the same positions in the GC-rich sequences. Two major transcription initiation sites were localized in the human PRPS1, one of the two was located 27 nucleotides downstream from the TATA-like sequence, while the upstream initiation site was in the TATA-like sequence. The promoter region of the human PRPS2 gene was also GC-rich and contained a TATA-like sequence, four Sp1 binding sites and a homopyrimidine stretch. The initiation sites were localized at 90 nucleotides upstream from the ATG initiation codon. Chloramphenicol acetyltransferase (CAT)/promoter fusion assays showed that a 2.0 kb region (human PRPS1) and a 1.1 kb region (human PRPS2) possessed the promoter activities in four cell lines. The CAT activities in the three human cell lines tended to correlate with the steady-state mRNA levels of the PRPS1 and PRPS2 genes. These results suggest that the 5' flanking regions cloned contribute to the cell-differential expression of these two genes.
Ishizuka
T
T
Department of Biochemistry, Chiba University School of Medicine, Japan.
Iizasa
T
T
Taira
M
M
Ishijima
S
S
Sonoda
T
T
Shimada
H
H
Nagatake
N
N
Tatibana
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D016466:CHO Cells; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D005260:Female; D015870:Gene Expression; D008040:Genetic Linkage; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D012268:Ribose-Phosphate Pyrophosphokinase / Q000235:genetics*; D016385:TATA Box; D014158:Transcription, Genetic; D014162:Transfection; D014960:X Chromosome
D007527:Isoenzymes; D012333:RNA, Messenger; D004247:DNA; D015500:Chloramphenicol O-Acetyltransferase; D012268:Ribose-Phosphate Pyrophosphokinase