PlantTFDB
Plant Transcription Factor Database
v4.0
Previous version: v1.0, v2.0, v3.0
Arabis alpina
GeBP Family
Species TF ID Description
KFK22018.1GeBP family protein
KFK22195.1GeBP family protein
KFK23649.1GeBP family protein
KFK24186.1GeBP family protein
KFK24583.1GeBP family protein
KFK24587.1GeBP family protein
KFK24588.1GeBP family protein
KFK25038.1GeBP family protein
KFK25657.1GeBP family protein
KFK26458.1GeBP family protein
KFK29030.1GeBP family protein
KFK30394.1GeBP family protein
KFK30638.1GeBP family protein
KFK30641.1GeBP family protein
KFK32172.1GeBP family protein
KFK33322.1GeBP family protein
KFK33325.1GeBP family protein
KFK36333.1GeBP family protein
KFK36347.1GeBP family protein
KFK36348.1GeBP family protein
KFK36349.1GeBP family protein
KFK36360.1GeBP family protein
KFK37902.1GeBP family protein
KFK40675.1GeBP family protein
KFK40940.1GeBP family protein
KFK40965.1GeBP family protein
KFK41181.1GeBP family protein
KFK41182.1GeBP family protein
KFK43271.1GeBP family protein
KFK43427.1GeBP 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