PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Juglans regia
HD-ZIP Family
Species TF ID Description
WALNUT_00000975-RAHD-ZIP family protein
WALNUT_00003701-RAHD-ZIP family protein
WALNUT_00005208-RAHD-ZIP family protein
WALNUT_00020183-RAHD-ZIP family protein
WALNUT_00017271-RAHD-ZIP family protein
WALNUT_00028267-RAHD-ZIP family protein
WALNUT_00015876-RAHD-ZIP family protein
WALNUT_00023724-RAHD-ZIP family protein
WALNUT_00011890-RAHD-ZIP family protein
WALNUT_00001657-RAHD-ZIP family protein
WALNUT_00026436-RAHD-ZIP family protein
WALNUT_00001591-RAHD-ZIP family protein
WALNUT_00003295-RAHD-ZIP family protein
WALNUT_00027862-RAHD-ZIP family protein
WALNUT_00019432-RAHD-ZIP family protein
WALNUT_00029689-RAHD-ZIP family protein
WALNUT_00006912-RAHD-ZIP family protein
WALNUT_00011814-RAHD-ZIP family protein
WALNUT_00014488-RAHD-ZIP family protein
WALNUT_00003114-RAHD-ZIP family protein
WALNUT_00017068-RAHD-ZIP family protein
WALNUT_00021290-RAHD-ZIP family protein
WALNUT_00021284-RAHD-ZIP family protein
WALNUT_00018990-RAHD-ZIP family protein
WALNUT_00011075-RAHD-ZIP family protein
WALNUT_00025365-RAHD-ZIP family protein
WALNUT_00000575-RAHD-ZIP family protein
WALNUT_00031675-RAHD-ZIP family protein
WALNUT_00001905-RAHD-ZIP family protein
WALNUT_00026034-RAHD-ZIP family protein
WALNUT_00023696-RAHD-ZIP family protein
WALNUT_00028098-RAHD-ZIP family protein
WALNUT_00020371-RAHD-ZIP family protein
WALNUT_00028862-RAHD-ZIP family protein
WALNUT_00029393-RAHD-ZIP family protein
WALNUT_00020265-RAHD-ZIP family protein
WALNUT_00010458-RAHD-ZIP family protein
WALNUT_00001748-RAHD-ZIP family protein
WALNUT_00020269-RAHD-ZIP family protein
WALNUT_00016560-RAHD-ZIP family protein
WALNUT_00019251-RAHD-ZIP family protein
WALNUT_00028018-RAHD-ZIP family protein
WALNUT_00014603-RAHD-ZIP family protein
WALNUT_00004372-RAHD-ZIP family protein
WALNUT_00001229-RAHD-ZIP family protein
WALNUT_00029066-RAHD-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