The Pepper WPP Domain Protein, CaWDP1, Acts as a Novel Negative Regulator of Drought Stress via ABA Signaling.
Plants are constantly challenged by various environmental stresses, including high salinity and drought, and they have evolved defense mechanisms to counteract the deleterious effects of these stresses. The plant hormone ABA regulates plant growth and developmental processes and mediates abiotic stress responses. Here, we report the identification and characterization of a novel CaWDP1 (Capsicum annuum) protein. The expression of CaWDP1 in pepper leaves was induced by ABA, drought and NaCl treatments, suggesting its role in the abiotic stress response. CaWDP1 proteins show conserved sequence homology with other known WDP1 proteins, and they are localized in the nucleus and cytoplasm. We generated CaWDP1-silenced peppers via virus-induced gene silencing (VIGS). We evaluated the responses of these CaWDP1-silenced pepper plants and CaWDP1-overexpressing (OX) transgenic Arabidopsis plants to ABA and drought. CaWDP1-silenced pepper plants displayed enhanced tolerance to drought stress, and this was characterized by low levels of leaf water loss in the drought-treated leaves. In contrast to CaWDP1-silenced plants, CaWDP1-OX plants exhibited an ABA-hyposensitive and drought-susceptible phenotype, which was accompanied by high levels of leaf water loss, low leaf temperatures, increased stomatal pore size and low expression levels of stress-responsive genes. Our results indicate that CaWDP1, a novel pepper negative regulator of ABA, regulates the ABA-mediated defense response to drought stress.
Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea.|These authors contributed equally to this work.
Chanmi
C
Park
Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea.|These authors contributed equally to this work.
Chae Woo
CW
Lim
Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea.|These authors contributed equally to this work.
Woonhee
W
Baek
Department of Physical Education, Chung-Ang University, Seoul 06911, Korea.|These authors contributed equally to this work.
Jung-Hyun
JH
Kim
Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea.
Sohee
S
Lim
Department of Bioscience and Bioinformatics, College of Natural Science, Myongji University, Yongin, Kyeonggi-Do17058, Korea.
Sang Hyon
SH
Kim
Department of Molecular Biology, PERI, Sejong University, Seoul 05000, Korea.
Kyung-Nam
KN
Kim
Department of Life Science (BK21 program), Chung-Ang University, Seoul, Korea.
Sung Chul
SC
Lee
D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D017360:Arabidopsis / Q000235:genetics; D002212:Capsicum / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D054712:Salinity; D036226:Seedlings / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction; D013312:Stress, Physiological
D010940:Plant Proteins; D000040:Abscisic Acid
Abscisic acid; CaWDP1; Drought stress; Pepper; Virus-induced gene silencing