PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Morus notabilis
HD-ZIP Family
Species TF ID Description
XP_010111761.1HD-ZIP family protein
XP_010112600.1HD-ZIP family protein
XP_010108964.1HD-ZIP family protein
XP_010104860.1HD-ZIP family protein
XP_010096374.1HD-ZIP family protein
XP_010096332.1HD-ZIP family protein
XP_010106292.1HD-ZIP family protein
XP_010095880.1HD-ZIP family protein
XP_010111372.1HD-ZIP family protein
XP_010098637.1HD-ZIP family protein
XP_010089303.1HD-ZIP family protein
XP_010099404.1HD-ZIP family protein
XP_010090889.1HD-ZIP family protein
XP_010099829.1HD-ZIP family protein
XP_010109438.1HD-ZIP family protein
XP_010103343.1HD-ZIP family protein
XP_010101726.1HD-ZIP family protein
XP_010107043.1HD-ZIP family protein
XP_010098443.1HD-ZIP family protein
XP_010100199.1HD-ZIP family protein
XP_010093963.1HD-ZIP family protein
XP_010100685.1HD-ZIP family protein
XP_010098082.1HD-ZIP family protein
XP_010109517.1HD-ZIP family protein
XP_010091553.1HD-ZIP family protein
XP_010107411.1HD-ZIP family protein
XP_010099679.1HD-ZIP family protein
XP_010098130.1HD-ZIP family protein
XP_010102406.1HD-ZIP family protein
XP_010098570.1HD-ZIP family protein
XP_010096931.1HD-ZIP family protein
XP_010101468.1HD-ZIP family protein
HD-ZIP Family Introduction

A homeobox (HB) encodes a protein domain, the homeodomain (HD), which is a conserved 60-amino acid motif present in transcription factors found in all the eukaryotic organisms. This 60-amino acid sequence folds into a characteristic three-helix structure that is able to interact specifically with DNA. Most HDs are able to bind DNA as monomers with high affinity, through interactions made by helix III (the so-called recognition helix) and a disordered N-terminal arm located beyond helix I. The high degree of conservation of this type of domain among diverse proteins from different kingdoms indicates that this structure is crucial to maintain the HD functionality and that the role played by this domain is vital.

Members of the HD-Zip family have a leucine zipper motif (LZ) immediately downstream of the HD. The two motifs are present in transcription factors found in species belonging to other eukaryotic kingdoms, but their association in a single protein is unique to plants. The HD is responsible for the specific binding to DNA, whereas LZ acts as a dimerization motif. HD-Zip proteins bind to DNA as dimers, and the absence of LZ absolutely abolishes their binding ability, which indicates that the relative orientation of the monomers, driven by this motif, is crucial for an efficient recognition of DNA.

Ariel FD, Manavella PA, Dezar CA, Chan RL.
The true story of the HD-Zip family.
Trends Plant Sci, 2007. 12(9): p. 419-26.
PMID: 17698401