CLONING AND CHARACTERIZATION OF THE PROMOTER REGION OF MONKEY THYMIDYLATE SYNTHASE GENE

Thymidylate synthase (TS) catalyzes the conversion of deoxyuridylate t o thymidylate. Promoter regions of the TS gene from three vertebrates, human, mouse and rat, have been analyzed so far. A unique inverted re peat was present in the promoter region of the human, but not in the m ouse and rat, TS genes, and the feature of the promoter region is cons iderably different between the human TS gene and the two rodent TS gen es. To examine whether the characteristics of the human TS gene promot er is intrinsic to human or primate, we cloned a DNA fragment containi ng the promoter region of the monkey TS gene and determined the nucleo tide sequence in this region. The nucleotide sequence in the promoter region of the monkey TS gene was revealed to have 88% homology with th at in the corresponding region of the human TS gene. The unique repeat ed structure mentioned above was also found in the monkey TS gene. Fur thermore, the Sp1-binding motif and the CACCC box were found to be con served in the monkey TS gene. The result of chloramphenicol acetyltran sferase assay suggested that the Sp1-binding motif and the CACCC box a re essential for the promoter activity of the monkey TS gene, as in th e case of the human TS gene.