Durga Madhab Swain1,2, Ranjan Kumar Sahoo1, Vineet Kumar Srivastava1, Baishnab Charan Tripathy3,2, Renu Tuteja1, Narendra Tuteja4,5. 1. International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India. 2. Department of Biotechnology, Ravenshaw University, Cuttack, Odisha, 753003, India. 3. School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India. 4. International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, 110067, India. narendra@icgeb.res.in. 5. Amity Institute of Microbial Technology, Amity University, Noida, 201313, India. narendra@icgeb.res.in.
Abstract
MAIN CONCLUSION: The present study provides evidence of a unique function of RGG1 in providing salinity stress tolerance in transgenic rice without affecting yield. It also provides a good example for signal transduction from the external environment to inside for enhanced agricultural production that withstands the extreme climatic conditions and ensures food security. The role of heterotrimeric G-proteins functioning as signalling molecules has not been studied as extensively in plants as in animals. Recently, their importance in plant stress signalling has been emerging. In this study, the function of rice G-protein γ subunit (RGG1) in the promotion of salinity tolerance in rice (Oryza sativa L. cv. IR64) was investigated. The overexpression of RGG1 driven by the CaMV35S promoter in transgenic rice conferred high salinity tolerance even in the presence of 200 mM NaCl. Transcript levels of antioxidative genes, i.e., CAT, APX, and GR, and their enzyme activities increased in salinity-stressed transgenic rice plants suggesting a better antioxidant system to cope the oxidative-damages caused by salinity stress. The RGG1-induced signalling events that conferred tolerance to salinity was mediated by increased gene expression of the enzymes that scavenged reactive oxygen species. In salinity-stressed RGG1 transgenic lines, the transcript levels of RGG2, RGB, RGA, DEP1, and GS3 also increased in addition to RGG1. These observations suggest that most likely the stoichiometry of the G-protein complex was not disturbed under stress. Agronomic parameters, endogenous sugar content (glucose and fructose) and hormones (GA3, zeatin and IAA) were also higher in the transgenic plants compared with the wild-type plants. A BiFC assay confirmed the interaction of RGG1 with different stress-responsive proteins which play active roles in signalling and prevention of aggregation of proteins under stress-induced perturbation. The present study will help in understanding the G-protein-mediated stress tolerance in plants.
MAIN CONCLUSION: The present study provides evidence of a unique function of RGG1 in providing salinity stress tolerance in transgenic rice without affecting yield. It also provides a good example for signal transduction from the external environment to inside for enhanced agricultural production that withstands the extreme climatic conditions and ensures food security. The role of heterotrimeric G-proteins functioning as signalling molecules has not been studied as extensively in plants as in animals. Recently, their importance in plant stress signalling has been emerging. In this study, the function of rice G-protein γ subunit (RGG1) in the promotion of salinity tolerance in rice (Oryza sativa L. cv. IR64) was investigated. The overexpression of RGG1 driven by the CaMV35S promoter in transgenic rice conferred high salinity tolerance even in the presence of 200 mM NaCl. Transcript levels of antioxidative genes, i.e., CAT, APX, and GR, and their enzyme activities increased in salinity-stressed transgenic rice plants suggesting a better antioxidant system to cope the oxidative-damages caused by salinity stress. The RGG1-induced signalling events that conferred tolerance to salinity was mediated by increased gene expression of the enzymes that scavenged reactive oxygen species. In salinity-stressed RGG1 transgenic lines, the transcript levels of RGG2, RGB, RGA, DEP1, and GS3 also increased in addition to RGG1. These observations suggest that most likely the stoichiometry of the G-protein complex was not disturbed under stress. Agronomic parameters, endogenous sugar content (glucose and fructose) and hormones (GA3, zeatin and IAA) were also higher in the transgenic plants compared with the wild-type plants. A BiFC assay confirmed the interaction of RGG1 with different stress-responsive proteins which play active roles in signalling and prevention of aggregation of proteins under stress-induced perturbation. The present study will help in understanding the G-protein-mediated stress tolerance in plants.
Authors: Sophie Alvarez; Swarup Roy Choudhury; Kumaran Sivagnanam; Leslie M Hicks; Sona Pandey Journal: J Proteome Res Date: 2015-05-19 Impact factor: 4.466
Authors: Qingyu Wu; Fang Xu; Lei Liu; Si Nian Char; Yezhang Ding; Byoung Il Je; Eric Schmelz; Bing Yang; David Jackson Journal: Proc Natl Acad Sci U S A Date: 2019-12-18 Impact factor: 11.205