PlantTFDB
PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Previous version: v3.0 v4.0
Trema orientale
HD-ZIP Family
Species TF ID Description
PON38600.1HD-ZIP family protein
PON42659.1HD-ZIP family protein
PON42886.1HD-ZIP family protein
PON43793.1HD-ZIP family protein
PON47409.1HD-ZIP family protein
PON62678.1HD-ZIP family protein
PON66451.1HD-ZIP family protein
PON67337.1HD-ZIP family protein
PON70051.1HD-ZIP family protein
PON70213.1HD-ZIP family protein
PON81208.1HD-ZIP family protein
PON82610.1HD-ZIP family protein
PON83861.1HD-ZIP family protein
PON85393.1HD-ZIP family protein
PON86044.1HD-ZIP family protein
PON88418.1HD-ZIP family protein
PON88567.1HD-ZIP family protein
PON90881.1HD-ZIP family protein
PON92156.1HD-ZIP family protein
PON92771.1HD-ZIP family protein
PON92795.1HD-ZIP family protein
PON97557.1HD-ZIP family protein
PON97722.1HD-ZIP family protein
PON97806.1HD-ZIP family protein
PON97838.1HD-ZIP family protein
PON98166.1HD-ZIP family protein
PON99981.1HD-ZIP family protein
POO00032.1HD-ZIP family protein
POO00969.1HD-ZIP family protein
POO01238.1HD-ZIP family protein
POO01858.1HD-ZIP family protein
POO02588.1HD-ZIP family protein
POO03760.1HD-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