IDENTIFICATION OF WRKY TRANSCRIPTION FACTORS FROM SAFFLOWER (Carthamus tinctorius L.) AND THEIR EXPRESSION IN RESPONSE TO ABIOTIC STRESS
M. SIVAKUMAR
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India.
M. PANDURANGAIAH
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India.
N. JAYAMMA
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India
N. JAGADEESH KUMAR
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India
B. VENKATESH
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India.
CHINTA SUDHAKAR
Department of Botany, Sri Krishnadevaraya University, Anantapuram 515 003, India.
*Author to whom correspondence should be addressed.
Abstract
WRKY TFs represent a large family of transcriptional regulators that play a key role in plant response to biotic and abiotic stresses. Safflower, Carthamus tinctorius, is cultivated for vegetable oil extracted from seeds. It is grown in semi-arid regions and is resistant to abiotic stresses such as drought, temperature and salinity. However, stress resilience in safflower is poorly understood. In the present study, by analyzing available EST data set, we identified 21 putative CtWRKYs in safflower. The CtWRKYs were classified into three groups based on the phylogeny of their WRKY domains. Majority of identified CtWRKYs categorized into group III. Also, abiotic stress response of five CtWRKYs was studied in safflower plants subjected to drought, temperature, cold, salt and dehydration stresses by qRT-PCR. All the CtWRKYs were responsive to multiple abiotic stresses, suggesting they positively or negatively affect plant resistance to various abiotic stresses. Our results will be useful for further functional characterization of CtWRKYs and stress tolerance in safflower.
Keywords: WRKYs, transcription factors, ESTs, safflower, Carthamus tinctorius, abiotic stresses