Reactive Oxygen Species (ROS) and ABA Signalling - Abscisic Acid: Metabolism, Transport and Signaling - page 186

GHR1 Guard cell hydrogen peroxide-resistant1

HSFs Heat shock transcription factor

Zat Zinc finger protein

WRKY WRKY transcription factors

SLAC1 S-type anion channel

GPCR G protein-coupled receptor

PYL/PYL/RCA ABA receptor

PP2C Type 2C protein phosphatase

SOD Superoxide dismutase

APX Ascorbate peroxidase

GPX Glutathione peroxidase

GST Glutathione-S-transferase

CAT Catalase

PLD Phospholipase dalpha1

PA Phosphatidic acid

PI3P Phosphatidylinositol 3-phosphate

GCA2 Growth controlled by abscisic acid 2

cGMP Cyclic guanosine monophosphate

ATHK Arabidopsis thaliana histidine kinase

HAB1 Hypersensitive to ABA 1

SWI3B Arabidopsis thaliana homologue of the yeast SWI3 subunit of

SWI/SNF chromatin-remodelling complexes

GPA1 G ʱ subunit

RCN1 Reticulocalbin 1

MEK1/2 Mitogen-activated protein kinase kinase 1/2

OXI1 Oxidative signal-inducible serine/threonine protein kinase 1

ANP1 MAPK kinase kinase

AtNDPK2 Nucleoside diphosphate kinase 2

CBL Calcineurin B-like

CIPK CBL-interacting protein kinases

AtRac1 Arabidopsis small guanosine triphosphatase (GTPase) protein

SNAC1 Stress-related NAC superfamily of transcription factors

ABP9 ABA-responsive-element (ABRE) binding protein 9

10.1 Introduction

Various abiotic stress conditions, including salinity, extremes of temperature and water
shortage, result in the accumulation of phytohormone abscisic acid (ABA) in plants.
This signalling molecule plays an important role in the regulation of plant growth and
development. These stresses are the principal causes of significant reductions in crop
yield. Stress tolerance is a complex phenomenon because plants might undergo multi-
ple stresses at the same time during their development. For example, ABA induces the
closure of stomata in the epidermis, which regulates transpiration and photosynthesis