PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Aethionema arabicum
HD-ZIP Family
Species TF ID Description
AA32G01145HD-ZIP family protein
AA40G00573HD-ZIP family protein
AA46G00133HD-ZIP family protein
AA38G00103HD-ZIP family protein
AA107G00002HD-ZIP family protein
AA46G00167HD-ZIP family protein
AA53G00281HD-ZIP family protein
AA10G00418HD-ZIP family protein
AA30G00184HD-ZIP family protein
AA33G00123HD-ZIP family protein
AA39G00606HD-ZIP family protein
AA251G00004HD-ZIP family protein
AA8G00057HD-ZIP family protein
AA21G00398HD-ZIP family protein
AA57G00018HD-ZIP family protein
AA61G00402HD-ZIP family protein
AA87G00143HD-ZIP family protein
AA54G00108HD-ZIP family protein
AA19G00212HD-ZIP family protein
AA21G00239HD-ZIP family protein
AA60G00132HD-ZIP family protein
AA61G00546HD-ZIP family protein
AA11G00061HD-ZIP family protein
AA53G00624HD-ZIP family protein
AA19G00255HD-ZIP family protein
AA6G00252HD-ZIP family protein
AA89G00009HD-ZIP family protein
AA19G00023HD-ZIP family protein
AA32G00026HD-ZIP family protein
AA21G00315HD-ZIP family protein
AA651G00001HD-ZIP family protein
AA57G00375HD-ZIP family protein
AA18G00127HD-ZIP family protein
AA15G00017HD-ZIP family protein
AA32G00513HD-ZIP family protein
AA31G00615HD-ZIP family protein
AA61G00473HD-ZIP family protein
AA39G00087HD-ZIP family protein
AA8G00317HD-ZIP family protein
AA290G00005HD-ZIP family protein
AA55G00037HD-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