PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Previous version: v3.0 v4.0
Oryza brachyantha
HD-ZIP Family
Species TF ID Description
OB08G25440.1HD-ZIP family protein
OB09G20040.1HD-ZIP family protein
OB08G22310.1HD-ZIP family protein
OB03G15380.1HD-ZIP family protein
OB04G27770.1HD-ZIP family protein
OB02G38180.1HD-ZIP family protein
OB03G16630.1HD-ZIP family protein
OB04G27300.1HD-ZIP family protein
OB10G16230.1HD-ZIP family protein
OB06G12390.1HD-ZIP family protein
OB10G25660.1HD-ZIP family protein
OB10G10250.1HD-ZIP family protein
OB09G23870.1HD-ZIP family protein
OB01G33620.1HD-ZIP family protein
OB09G15670.1HD-ZIP family protein
OB06G33700.1HD-ZIP family protein
OB02G28610.1HD-ZIP family protein
OB07G25790.1HD-ZIP family protein
OB03G17420.1HD-ZIP family protein
OB09G18680.1HD-ZIP family protein
OB06G12380.1HD-ZIP family protein
OB02G13290.1HD-ZIP family protein
OB10G17260.1HD-ZIP family protein
OB05G34350.1HD-ZIP family protein
OB04G32930.1HD-ZIP family protein
OB02G35000.1HD-ZIP family protein
OB01G40650.1HD-ZIP family protein
OB03G35020.1HD-ZIP family protein
OB12G25330.1HD-ZIP family protein
OB09G23660.1HD-ZIP family protein
OB01G16410.1HD-ZIP family protein
OB04G29090.1HD-ZIP family protein
OB03G10760.1HD-ZIP family protein
OB10G20600.1HD-ZIP family protein
OB06G16250.1HD-ZIP family protein
OB10G26620.1HD-ZIP family protein
OB08G12470.1HD-ZIP family protein
OB08G18460.1HD-ZIP family protein
OB01G42420.1HD-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