Genomewide Expression and Functional Interactions of Genes under Drought Stress in Maize.
A genomewide transcriptome assay of two subtropical genotypes of maize was used to observe the expression of genes at seedling stage of drought stress. The number of genes expressed differentially was greater in HKI1532 (a drought tolerant genotype) than in PC3 (a drought sensitive genotype), indicating primary differences at the transcriptional level in stress tolerance. The global coexpression networks of the two genotypes differed significantly with respect to the number of modules and the coexpression pattern within the modules. A total of 174 drought-responsive genes were selected from HKI1532, and their coexpression network revealed key correlations between different adaptive pathways, each cluster of the network representing a specific biological function. Transcription factors related to ABA-dependent stomatal closure, signalling, and phosphoprotein cascades work in concert to compensate for reduced photosynthesis. Under stress, water balance was maintained by coexpression of the genes involved in osmotic adjustments and transporter proteins. Metabolism was maintained by the coexpression of genes involved in cell wall modification and protein and lipid metabolism. The interaction of genes involved in crucial biological functions during stress was identified and the results will be useful in targeting important gene interactions to understand drought tolerance in greater detail.
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Nepolean
0000-0002-6263-539X
N
Thirunavukkarasu
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Rinku
R
Sharma
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Nidhi
N
Singh
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Kaliyugam
0000-0003-2535-1176
K
Shiriga
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Sweta
S
Mohan
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Swati
S
Mittal
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Shikha
S
Mittal
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Mallana Gowdra
MG
Mallikarjuna
Centre for Agricultural Bioinformatics, Indian Agricultural Statistics Research Institute, Pusa, Library Avenue, New Delhi 110 012, India.
Atmakuri Ramakrishna
AR
Rao
National Research Centre on Plant Biotechnology, Pusa Campus, New Delhi 110012, India.
Prasanta Kumar
PK
Dash
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India.
Firoz
F
Hossain
Division of Genetics, Indian Agricultural Research Institute, New Delhi 110012, India; Borlaug Institute for South Asia (BISA), New Delhi 110012, India.
Hari Shanker
HS
Gupta