Deoxyribonucleic acid-protein interactions associated with transcriptional initiation of the mouse testis-specific cytochrome c gene.
Transcriptional regulation of the mouse testis-specific cytochrome c (cyt. cT) gene was studied by examining DNA-protein interactions in its proximal promoter. Testicular and liver nuclear proteins bound to the cyt. cT gene at sites -105 to -81, +87 to +113, and +146 to +169, suggesting interactions with ubiquitous nuclear proteins. Protein present in liver nuclear extracts bound to a fourth site at -176 to -125, whereas protein present in testicular nuclear extracts bound to a subregion of this site at -176 to -140. The sequence from -136 to -127, bound by liver but not testicular nuclear proteins, is similar to that of the binding site of a somatic c-mos repressor protein. Lastly, different nuclear proteins from mouse liver and testis bound to a region from -18 to +31 that contains a putative Y box at -13 to -2. Mobility shift assays, Southwestern blots, and immunoprecipitation studies have established that this putative Y box binds a 52-kDa mouse testicular homologue of the Xenopus germ cell-specific Y-box protein and a competing 50-kDa protein present in both liver and testis nuclear extracts. These data suggest that the testis-specific expression of the mouse cyt. cT gene during spermatogenesis may be regulated by the differential binding of tissue-specific nuclear proteins to its proximal promoter region.
Yiu
G K
GK
Department of Biology, Tufts University, Medford, Massachusetts 02155, USA.
Murray
M T
MT
Hecht
N B
NB
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D003574:Cytochrome c Group / Q000378:metabolism*; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D013737:Testis / Q000378:metabolism*; D014981:Xenopus
D003574:Cytochrome c Group; D009687:Nuclear Proteins; D004247:DNA