Transcription Factors Involved in ABA Signaling - Abscisic Acid: Metabolism, Transport and Signaling - page 218

Chapter 11
Transcription Factors Involved
in ABA Signaling

Soo Young Kim

Abstract Abscisic acid plays an important regulatory role in seed development
and adaptive responses to abiotic stresses in vegetative tissues. The major part of
the ABA function entails gene expression events. Various genome-wide transcrip-
tome analyses indicate that ABA regulates the largest number of genes among
major plant hormones. Promoter analyses of the ABA-regulated genes revealed
that cis -elements sharing the PyACGTGGC core sequence are present in many
ABA-responsive genes. The element is generally known as ABA response ele-
ment (ABRE), and a subfamily of basic leucine zipper (bZIP) proteins has been
identified that mediate ABA regulation through the ABRE. Other cis -elements and
cognate transcription factors (TFs) involved in ABA-dependent transcription have
also been identified by traditional approaches. Additionally, numerous TFs have
been reported to regulate ABA-responsive gene expression by reverse genetics
means. In this article, I will review ABA-dependent transcription, focusing on the
Arabidopsis TFs whose in vivo functions have been experimentally demonstrated.

Keywords Transcription factors · Abscisic acid (ABA) · Gene regulation

11.1 Introduction

An analysis of public Affymetrix ATH1 GeneChip microarray data sets revealed
that ABA has the most profound effect on gene expression among seven plant
hormones (i.e., ABA, GA, IAA, ET, CK, BR, and MJ) (Nemhauser et al. 2006 ).
According to the analysis, ABA affects the expression of 2,936 genes. Matsui