PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Oropetium thomaeum
HD-ZIP Family
Species TF ID Description
Oropetium_20150105_02318AHD-ZIP family protein
Oropetium_20150105_05617AHD-ZIP family protein
Oropetium_20150105_19150AHD-ZIP family protein
Oropetium_20150105_12291AHD-ZIP family protein
Oropetium_20150105_20362AHD-ZIP family protein
Oropetium_20150105_20971AHD-ZIP family protein
Oropetium_20150105_00219AHD-ZIP family protein
Oropetium_20150105_00326AHD-ZIP family protein
Oropetium_20150105_17088AHD-ZIP family protein
Oropetium_20150105_00593AHD-ZIP family protein
Oropetium_20150105_21050AHD-ZIP family protein
Oropetium_20150105_17090AHD-ZIP family protein
Oropetium_20150105_05733AHD-ZIP family protein
Oropetium_20150105_12247AHD-ZIP family protein
Oropetium_20150105_11810AHD-ZIP family protein
Oropetium_20150105_20439AHD-ZIP family protein
Oropetium_20150105_02902AHD-ZIP family protein
Oropetium_20150105_02507AHD-ZIP family protein
Oropetium_20150105_05962AHD-ZIP family protein
Oropetium_20150105_16654AHD-ZIP family protein
Oropetium_20150105_14357AHD-ZIP family protein
Oropetium_20150105_00400AHD-ZIP family protein
Oropetium_20150105_27001AHD-ZIP family protein
Oropetium_20150105_16258AHD-ZIP family protein
Oropetium_20150105_06595AHD-ZIP family protein
Oropetium_20150105_20035AHD-ZIP family protein
Oropetium_20150105_20218AHD-ZIP family protein
Oropetium_20150105_14064AHD-ZIP family protein
Oropetium_20150105_23320AHD-ZIP family protein
Oropetium_20150105_06618AHD-ZIP family protein
Oropetium_20150105_21320AHD-ZIP family protein
Oropetium_20150105_19848AHD-ZIP family protein
Oropetium_20150105_18232AHD-ZIP family protein
Oropetium_20150105_12589AHD-ZIP family protein
Oropetium_20150105_13384AHD-ZIP family protein
Oropetium_20150105_17187AHD-ZIP family protein
Oropetium_20150105_21155AHD-ZIP family protein
Oropetium_20150105_18558AHD-ZIP family protein
Oropetium_20150105_04359AHD-ZIP family protein
Oropetium_20150105_08374AHD-ZIP family protein
Oropetium_20150105_17972AHD-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