Participation of oligomerization through C-terminal D domain region of Sp1 in DNA binding.
Transcription factor Sp1 is a Cys2His2-type zinc finger protein that specifically binds to GC-boxes on numerous viral and cellular genes. In this study, we prepared several Sp1 mutant peptides Sp1 (530-696) containing zinc finger region and the domain D, and Sp1 (530--623) containing only zinc finger region, and then investigated the participation of the C-terminal domain D of Sp1 for GC-box binding. Gel mobility shift assays demonstrate that Sp1 (530--696) evidently shows DNA-binding modes different from Spl (530--623) and that the Sp1 mutant containing the domain D self-interacts directly. Domain D may play an important role in the synergistic activation of Sp1 by the stacking of tetramers. A novel model for Sp1 oligomerization has also been proposed.
Matsushita
K
K
Institute for Chemical Research, Kyoto University, Uji, Japan.
Hagihara
M
M
Sugiura
Y
Y
D000595:Amino Acid Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D004247:DNA / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D013539:Simian virus 40 / Q000235:genetics; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D020080:Tandem Repeat Sequences
D016329:Sp1 Transcription Factor; D004247:DNA