Plant Transcription Factor Database
Previous version: v3.0
Brassica napus
GeBP Family
Species TF ID Description
GSBRNA2T00005865001GeBP family protein
GSBRNA2T00006750001GeBP family protein
GSBRNA2T00010887001GeBP family protein
GSBRNA2T00015283001GeBP family protein
GSBRNA2T00034633001GeBP family protein
GSBRNA2T00035086001GeBP family protein
GSBRNA2T00036772001GeBP family protein
GSBRNA2T00037476001GeBP family protein
GSBRNA2T00038423001GeBP family protein
GSBRNA2T00044558001GeBP family protein
GSBRNA2T00049021001GeBP family protein
GSBRNA2T00049914001GeBP family protein
GSBRNA2T00049915001GeBP family protein
GSBRNA2T00051947001GeBP family protein
GSBRNA2T00056359001GeBP family protein
GSBRNA2T00066232001GeBP family protein
GSBRNA2T00069226001GeBP family protein
GSBRNA2T00070582001GeBP family protein
GSBRNA2T00073890001GeBP family protein
GSBRNA2T00093807001GeBP family protein
GSBRNA2T00096236001GeBP family protein
GSBRNA2T00097456001GeBP family protein
GSBRNA2T00098212001GeBP family protein
GSBRNA2T00098213001GeBP family protein
GSBRNA2T00105319001GeBP family protein
GSBRNA2T00105654001GeBP family protein
GSBRNA2T00108266001GeBP family protein
GSBRNA2T00109484001GeBP family protein
GSBRNA2T00111212001GeBP family protein
GSBRNA2T00114555001GeBP family protein
GSBRNA2T00114560001GeBP family protein
GSBRNA2T00116056001GeBP family protein
GSBRNA2T00124135001GeBP family protein
GSBRNA2T00131124001GeBP family protein
GSBRNA2T00133835001GeBP family protein
GSBRNA2T00144257001GeBP family protein
GSBRNA2T00149687001GeBP family protein
GSBRNA2T00154493001GeBP 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