Identification of the cis-elements required for transcriptional control of the Chinese hamster ovary APRT gene

• Published in: Gene Vol. 159; no. 2; pp. 175 - 180
• Main Authors: She, Bin-Ru, Taylor, Milton W.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 1995
• Subjects: adenine phosphoribosyltransferase; Adenine Phosphoribosyltransferase - biosynthesis; Adenine Phosphoribosyltransferase - genetics; Animals; Base Sequence; Binding Sites; CHO Cells; Cricetinae; DNA Mutational Analysis; DNA-Binding Proteins - metabolism; GC-box-binding factor; Gene Expression Regulation, Enzymologic; linker-scanning; Molecular Sequence Data; Promoter Regions, Genetic - genetics; Protein Binding; Sp1 Transcription Factor - metabolism; Spl; transcription start point; Transcription, Genetic; nt; LS; CHO; Inr; Spl; bp; tsp; linker-scanning; adenine phosphoribosyltransferase; Δ; DDT; EMSA; TBE; kb; oligo; wt; SSC; SDS; GC-box-binding factor; PAGE; transcription start point; GCF; PIPES; APRT; PolIk; PMSF; CAT
• ISSN: 0378-1119; 1879-0038
• DOI: 10.1016/0378-1119(95)00024-Z

Transcriptional regulation of the Chinese hamster ovary (CHO) adenine phosphoribosyltransferase-encoding gene (APRT) was studied. The 5′ region of the CHO APRT is G+C-rich, but lacking TATA or CCAAT boxes. RNase protection assays indicate that it contains multiple transcription start points ( tsp). A tsp 64 bp upstream from the translation start codon is denoted as + 1. Linker-scanning (LS) mutation analysis indicates that the −33 to + 19 region is important in regulating APRT transcription. Mutations in the −23 to −14 region abolish transcription initiated from the −23 downstream region. An unidentified protein complex binds to this region. Three Spl-binding sites are found in the APRT promoter; however, mutations of the Sp1-binding sites do not reduce APR T transcription. Mutations at two putative GCF-binding sites increase levels of transcription.