Figure 2.

The POU_S domain is located on opposite sides of the POU_H domain on octamer and (OCTA⁻)TAATGARAT sites. Shown are the cleavage products generated after crosslinking of POU_S-UC54 and POU_H-UC7 proteins to the upper strands of the octamer (lanes 2 and 3) and the (OCTA⁻)TAATGARAT (lanes 5 and 6) sites, as indicated. Lanes 1 and 4 (A+G), purine-cleavage pattern of the probe indicated. In lanes 2, 3, 5, and 6, uppermost bands represent uncleaved DNA. Brackets mark the limits of the two sequences on the autoradiographs, and arrows indicate the directionality of each consensus motif. The two binding sites are cloned into the same plasmid in opposite orientations. ∗, Cleavage product mapping to flanking polylinker sequence, probably resulting from non-octamer-site binding. (Lower) Summary of positions of crosslink-induced cleavage. Dashed line indicates lower-yield cleavage product.