DNA binding by bZIP-type coiled-coil proteins can be inhibited
by dominant negative versions of the proteins in which the Nterminalbasic region is replaced by an acidic extension. Photocontrolof bZIP function can be achieved by introducing intramolecularazobenzene-based crosslinkers into dominant negatives.
We show that the largest degree of photocontrol is achieved
when the crosslinker is introduced into the zipper region
of the dominant negative between Cys residues placed at
f sites in the heptad segment showing the highest intrinsic helical propensity. The overall affinity of the dominant negative can then be tuned by varying the length of the acidic extension