Analysis of drought-responsive signalling network in two contrasting rice cultivars using transcriptome-based approach.
Traditional cultivars of rice in India exhibit tolerance to drought stress due to their inherent genetic variations. Here we present comparative physiological and transcriptome analyses of two contrasting cultivars, drought tolerant Dhagaddeshi (DD) and susceptible IR20. Microarray analysis revealed several differentially expressed genes (DEGs) exclusively in DD as compared to IR20 seedlings exposed to 3 h drought stress. Physiologically, DD seedlings showed higher cell membrane stability and differential ABA accumulation in response to dehydration, coupled with rapid changes in gene expression. Detailed analyses of metabolic pathways enriched in expression data suggest interplay of ABA dependent along with secondary and redox metabolic networks that activate osmotic and detoxification signalling in DD. By co-localization of DEGs with QTLs from databases or published literature for physiological traits of DD and IR20, candidate genes were identified including those underlying major QTL qDTY1.1in DD. Further, we identified previously uncharacterized genes from both DD and IR20 under drought conditions including OsWRKY51, OsVP1 and confirmed their expression by qPCR in multiple rice cultivars. OsFBK1 was also functionally validated in susceptible PB1 rice cultivar and Arabidopsis for providing drought tolerance. Some of the DEGs mapped to the known QTLs could thus, be of potential significance for marker-assisted breeding.
Interdisciplinary Centre for Plant Genomics, University of Delhi South Campus, New Delhi - 110021, India.
Pratikshya
P
Borah
Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi - 110021, India.
Eshan
E
Sharma
Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi - 110021, India.
Amarjot
A
Kaur
Indira Gandhi Agricultural University, Raipur - 492012, India.
Girish
G
Chandel
Department of Agricultural Research and Education, Indian Council of Agricultural Research, New Delhi - 110012, India.
Trilochan
T
Mohapatra
Interdisciplinary Centre for Plant Genomics, University of Delhi South Campus, New Delhi - 110021, India.|Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi - 110021, India.
Sanjay
S
Kapoor
Interdisciplinary Centre for Plant Genomics, University of Delhi South Campus, New Delhi - 110021, India.|Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi - 110021, India.
Jitendra P
JP
Khurana
D000222:Adaptation, Physiological / Q000235:genetics; D002874:Chromosome Mapping; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D007194:India; D012275:Oryza / Q000235:genetics* / Q000254:growth & development; D010641:Phenotype; D040641:Quantitative Trait Loci / Q000235:genetics*; D036226:Seedlings / Q000235:genetics* / Q000254:growth & development; D013312:Stress, Physiological / Q000235:genetics; D059467:Transcriptome / Q000235:genetics*