PlantTFDB
PlantRegMap/PlantTFDB v5.0
Plant Transcription Factor Database
Zea mays
GeBP Family
Species TF ID Description
EF517601.1_FGP010GeBP family protein
GRMZM2G006871_P01GeBP family protein
GRMZM2G008558_P01GeBP family protein
GRMZM2G008558_P02GeBP family protein
GRMZM2G026417_P01GeBP family protein
GRMZM2G030458_P01GeBP family protein
GRMZM2G036966_P01GeBP family protein
GRMZM2G036966_P02GeBP family protein
GRMZM2G041818_P01GeBP family protein
GRMZM2G066373_P01GeBP family protein
GRMZM2G075122_P01GeBP family protein
GRMZM2G075122_P02GeBP family protein
GRMZM2G082318_P01GeBP family protein
GRMZM2G083886_P01GeBP family protein
GRMZM2G092409_P01GeBP family protein
GRMZM2G125239_P01GeBP family protein
GRMZM2G125239_P02GeBP family protein
GRMZM2G125239_P03GeBP family protein
GRMZM2G134866_P01GeBP family protein
GRMZM2G134866_P02GeBP family protein
GRMZM2G155252_P01GeBP family protein
GRMZM2G162405_P01GeBP family protein
GRMZM2G162405_P02GeBP family protein
GRMZM2G174240_P01GeBP family protein
GRMZM2G392516_P01GeBP family protein
GRMZM2G423292_P01GeBP family protein
GRMZM5G868875_P01GeBP family protein
GRMZM5G868875_P02GeBP family protein
GeBP Family Introduction

Understanding the role of transcription factors (TFs) is essential in reconstructing developmental regulatory networks. The plant-specific GeBP TF family of Arabidopsis thaliana (Arabidopsis) comprises 21 members, all of unknown function. A subset of four members, the founding member GeBP and GeBP-like proteins (GPL) 1, 2, and 3, shares a conserved C-terminal domain. Here we report that GeBP/GPL genes represent a newly defined class of leucine-zipper (Leu-zipper) TFs and that they play a redundant role in cytokinin hormone pathway regulation. Specifically, we demonstrate using yeast, in vitro, and split-yellow fluorescent protein in planta assays that GeBP/GPL proteins form homo- and heterodimers through a noncanonical Leu-zipper motif located in the C-terminal domain. A triple loss-of-function mutant of the three most closely related genes gebp gpl1 gpl2 shows a reduced sensitivity to exogenous cytokinins in a subset of cytokinin responses such as senescence and growth, whereas root inhibition is not affected. We find that transcript levels of type-A cytokinin response genes, which are involved in the negative feedback regulation of cytokinin signaling, are higher in the triple mutant. Using a GPL version that acts as a constitutive transcriptional activator, we show that the regulation of Arabidopsis response regulators (ARRs) is mediated by at least one additional, as yet unknown, repressor acting genetically downstream in the GeBP/GPL pathway. Our results indicate that GeBP/GPL genes encode a new class of unconventional Leu-zipper TF proteins and suggest that their role in the cytokinin pathway is to antagonize the negative feedback regulation on ARR genes to trigger the cytokinin response.

Chevalier F, Perazza D, Laporte F, Le Henanff G, Hornitschek P, Bonneville JM, Herzog M, Vachon G
GeBP and GeBP-Like Proteins Are Noncanonical Leucine-Zipper Transcription Factors That Regulate Cytokinin Response in Arabidopsis
Plant Physiol. 2008 Mar;146(3):1142-54.
PMID: 18162594