PlantTFDB
PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Parasponia andersonii
HD-ZIP Family
Species TF ID Description
PON32251.1HD-ZIP family protein
PON33292.1HD-ZIP family protein
PON33352.1HD-ZIP family protein
PON33671.1HD-ZIP family protein
PON34152.1HD-ZIP family protein
PON35789.1HD-ZIP family protein
PON39010.1HD-ZIP family protein
PON40205.1HD-ZIP family protein
PON41447.1HD-ZIP family protein
PON41658.1HD-ZIP family protein
PON43145.1HD-ZIP family protein
PON43810.1HD-ZIP family protein
PON44444.1HD-ZIP family protein
PON44485.1HD-ZIP family protein
PON46351.1HD-ZIP family protein
PON47405.1HD-ZIP family protein
PON50831.1HD-ZIP family protein
PON54337.1HD-ZIP family protein
PON54767.1HD-ZIP family protein
PON56125.1HD-ZIP family protein
PON57028.1HD-ZIP family protein
PON60882.1HD-ZIP family protein
PON64301.1HD-ZIP family protein
PON65591.1HD-ZIP family protein
PON67486.1HD-ZIP family protein
PON67834.1HD-ZIP family protein
PON68743.1HD-ZIP family protein
PON71997.1HD-ZIP family protein
PON73539.1HD-ZIP family protein
PON75009.1HD-ZIP family protein
PON75470.1HD-ZIP family protein
PON76798.1HD-ZIP family protein
PON78766.1HD-ZIP family protein
PON78799.1HD-ZIP family protein
PON80817.1HD-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