Basic leucine zipper (bZIP) domain of uncharaterized BZIP transcription factors with similarity to Triticum aestivum HBP-1b: a DNA-binding and dimerization domain
This subfamily is composed primarily of uncharacterized bZIP transciption factors from flowering plants, mosses, clubmosses, and algae. Included in this subfamily is wheat HBP-1b, which contains a C-terminal DOG1 domain, which is a specific plant regulator for seed dormancy. bZIP factors act in networks of homo and heterodimers in the regulation of a diverse set of cellular processes. The bZIP structural motif contains a basic region and a leucine zipper, composed of alpha helices with leucine residues 7 amino acids apart, which stabilize dimerization with a parallel leucine zipper domain. Dimerization of leucine zippers creates a pair of the adjacent basic regions that bind DNA and undergo conformational change. Dimerization occurs in a specific and predictable manner resulting in hundreds of dimers having unique effects on transcription.