PlantTFDB
PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Quercus suber
HD-ZIP Family
Species TF ID Description
XP_023870350.1HD-ZIP family protein
XP_023872404.1HD-ZIP family protein
XP_023872405.1HD-ZIP family protein
XP_023874761.1HD-ZIP family protein
XP_023875609.1HD-ZIP family protein
XP_023879166.1HD-ZIP family protein
XP_023880884.1HD-ZIP family protein
XP_023881582.1HD-ZIP family protein
XP_023881583.1HD-ZIP family protein
XP_023881584.1HD-ZIP family protein
XP_023884520.1HD-ZIP family protein
XP_023885509.1HD-ZIP family protein
XP_023885611.1HD-ZIP family protein
XP_023885612.1HD-ZIP family protein
XP_023885965.1HD-ZIP family protein
XP_023888163.1HD-ZIP family protein
XP_023888470.1HD-ZIP family protein
XP_023894305.1HD-ZIP family protein
XP_023898511.1HD-ZIP family protein
XP_023898631.1HD-ZIP family protein
XP_023898633.1HD-ZIP family protein
XP_023904346.1HD-ZIP family protein
XP_023904347.1HD-ZIP family protein
XP_023904569.1HD-ZIP family protein
XP_023904570.1HD-ZIP family protein
XP_023905908.1HD-ZIP family protein
XP_023910485.1HD-ZIP family protein
XP_023910616.1HD-ZIP family protein
XP_023915053.1HD-ZIP family protein
XP_023915054.1HD-ZIP family protein
XP_023915056.1HD-ZIP family protein
XP_023915057.1HD-ZIP family protein
XP_023915058.1HD-ZIP family protein
XP_023916795.1HD-ZIP family protein
XP_023918167.1HD-ZIP family protein
XP_023919022.1HD-ZIP family protein
XP_023919941.1HD-ZIP family protein
XP_023919942.1HD-ZIP family protein
XP_023919943.1HD-ZIP family protein
XP_023920525.1HD-ZIP family protein
XP_023920526.1HD-ZIP family protein
XP_023920527.1HD-ZIP family protein
XP_023921420.1HD-ZIP family protein
XP_023926843.1HD-ZIP family protein
XP_023928204.1HD-ZIP family protein
XP_023929196.1HD-ZIP family protein
XP_023929344.1HD-ZIP family protein
XP_023929345.1HD-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