TdIF1 Recognizes a Specific DNA Sequence through Its Helix-Turn-Helix and AT-Hook Motifs to Regulate Gene Transcription
Figure 3
TdIF1 preferentially recognizes 5′-GNTGCATG-3′ following an AT-tract.
(A) Sequences of the biotin-labelled AT-rich probe and the competitors used. Asterisks indicate replaced residues in the AT-tract or 5′-GNTGCATG-3′ motifs. (B) Competitive EMSA. All reaction mixtures contained 5 pmol of biotin-labelled AT-rich probe. Purified His-TdIF1 (100 ng) was incubated in the reaction mixture alone or with competitors (5, 15, or 45 pmol) as indicated (lanes 2–14). (C) Competitive EMSA using TdIF1mtHTH2, which has mutations in the HTH. TdIF1mtHTH2 (200 ng) or wild-type TdIF1 (100 ng) was incubated with biotin-labelled AT-rich probe alone or with competitors (15 or 45 pmol), as indicated.