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Isolation and characterization of the hamster gadd153 gene. Activation of promoter activity by agents that damage DNA.

The Journal of biological chemistry (1990-09-25)
J D Luethy, J Fargnoli, J S Park, A J Fornace, N J Holbrook
RÉSUMÉ

A group of five cDNA clones, representing the gadd genes, were recently isolated from Chinese hamster ovary (CHO) cells as genes induced upon growth arrest and after DNA damage (Fornace, A. J., Jr., Nebert, D. W., Hollander, M. C., Luethy, J. D., Papathanasiou, M., Fargnoli, J., and Holbrook, N. J. (1989) Mol. Cell. Biol. 9, 4196-4203). We have isolated and characterized one of these genes, gadd153. The gene spans five kilobases and contains four exons. The 5'-flanking region of the gene, within 420 base pairs of the transcription initiation site, contains a number of cis elements associated with transcriptional regulation in other genes. These include a Hogness box, ATAAAA, an inverted GCCAAT box; seven SP1 transcription factor binding sites, and an AP-1 site. This region is rich in G + C content (greater than 70%) and contains an unusually long stretch of alternating CpG residues. The 800-base pair region immediately upstream of the transcription start site can drive expression of the bacterial chloramphenicol acetyltransferase (CAT) gene, but only in its endogenous orientation, in three different cell lines: HeLa, CHO, and Jurkat. The gadd153 promoter is strongly activated by methyl methanesulfonate, hydrogen peroxide, and UV irradiation, but not by growth arrest signals. This suggests that separate and very different regulatory pathways are involved in the induction of the gadd153 gene by growth cessation and DNA damage.