Molecular cloning and nuclear localization of ATBP, a novel (A+T)-stretch-binding protein of Sarcophaga peregrina (flesh fly).

Previously, we purified a DNA-binding protein, named ATBP, from cultured Sarcophaga cells. This protein was found to bind specifically to (A+T) stretches that locate in the 5'-upstream region and the intron of the Sarcophaga lectin gene [Matsui, M., Kobayashi, A., Kubo, T. & Natori, S. (1994) Eur. J. Biochem. 219, 449-454]. Here, we report molecular cloning of a cDNA for ATBP. The cDNA encoded a protein with two zinc-finger motifs, an acidic domain, two glutamine-rich domains and a glutamine run. Immunofluorescence study revealed that ATBP was localized in the nuclei. Thus, ATBP is possibly a transcription factor for genes having (A+T) stretches in their promoter and/or enhancer regions.