Kumar Anil, Kumar Varun, Dubey Arvind Kumar, Ansari Mohd Akram, Narayan Shiv, Kumar Sanoj, Pandey Vivek, Pande Veena, Sanyal Indraneel
Plant Transgenic Laboratory, Molecular Biology and Biotechnology Division, CSIR-National Botanical Research Institute, Lucknow, India.
Department of Biotechnology, Bhimtal Campus, Kumaun University, Nainital, India.
Physiol Mol Biol Plants. 2021 May;27(5):923-944. doi: 10.1007/s12298-021-00999-z. Epub 2021 May 6.
Glutaredoxins (Grxs) are short, cysteine-rich glutathione (GSH)-mediated oxidoreductases. In this study, a chickpea ( L.) [ ()] gene has been selected based on screening experiments with two contrasting varieties of chickpea, PUSA-362 (drought-tolerant) and ICC-1882 (drought-sensitive) under drought and salinity. The tolerant variety showed higher gene expression, as compared to less in the sensitive variety, under both the stresses. The gene was then over-expressed in and were exposed to drought and salinity. The over-expression of elevated the activity of glutaredoxin, which induced antioxidant enzymes (glutathione reductase; GR, glutathione peroxidase; GPX, catalase; CAT, ascorbate peroxidase; APX, glutathione-S-transferase; GST, superoxide dismutase; SOD, monodehydroascorbate reductase; MDHAR, and dehydroascorbate reductase; DHAR), antioxidants (GSH and ascorbate) and stress-responsive amino acids (cysteine and proline). Enhancement in the antioxidant defense system possibly administered tolerance in transgenics against both stresses. reduced stress markers (HO, TBARS, and electrolyte leakage) and enhanced root growth, seed germination, and survival against both stresses. The physiological parameters (net photosynthesis; , water use efficiency; WUE, stomatal conductance; , transpiration; , electron transport rate; ETR, and photochemical quenching; P), chlorophylls and carotenoids, were improved in the transgenics during both stresses, that maintained the photosynthetic apparatus and protected the plants from damage. The enhanced activity of the cysteine biosynthesis enzyme, o-acetylserine (thiol) lyase (OAS-TL), increased the cysteine level in the transgenics, which elevated glutathione biosynthesis to maintain the ascorbate-glutathione cycle under both stresses. This investigation verified that the gene provides tolerance against salinity and drought, maintaining physiological and morphological performances, and could be exploited for genetic engineering approaches to overcome both the stresses in various crops.
The online version contains supplementary material available at 10.1007/s12298-021-00999-z.
谷氧还蛋白（Grxs）是一类短小的、富含半胱氨酸的、由谷胱甘肽（GSH）介导的氧化还原酶。在本研究中，基于对鹰嘴豆两个对比品种PUSA - 362（耐旱）和ICC - 1882（干旱敏感）在干旱和盐胁迫下的筛选实验，选择了一个鹰嘴豆（L.）[（）]基因。在两种胁迫条件下，耐旱品种的该基因表达量高于敏感品种。随后该基因在中过表达，并使其遭受干旱和盐胁迫。该基因的过表达提高了谷氧还蛋白的活性，诱导了抗氧化酶（谷胱甘肽还原酶；GR、谷胱甘肽过氧化物酶；GPX、过氧化氢酶；CAT、抗坏血酸过氧化物酶；APX、谷胱甘肽 - S - 转移酶；GST、超氧化物歧化酶；SOD、单脱氢抗坏血酸还原酶；MDHAR和脱氢抗坏血酸还原酶；DHAR）、抗氧化剂（GSH和抗坏血酸）以及胁迫响应氨基酸（半胱氨酸和脯氨酸）的产生。抗氧化防御系统的增强可能赋予了转基因植株对两种胁迫的耐受性。降低了胁迫标记物（HO、TBARS和电解质渗漏），并增强了根系生长、种子萌发以及对两种胁迫的耐受性。在两种胁迫期间，转基因植株的生理参数（净光合速率；、水分利用效率；WUE、气孔导度；、蒸腾作用；、电子传递速率；ETR和光化学猝灭；P）、叶绿素和类胡萝卜素均得到改善，这维持了光合机构并保护植物免受损伤。半胱氨酸生物合成酶o - 乙酰丝氨酸（硫醇）裂解酶（OAS - TL）活性的增强增加了转基因植株中的半胱氨酸水平，从而提高了谷胱甘肽的生物合成，以在两种胁迫下维持抗坏血酸 - 谷胱甘肽循环。本研究证实该基因赋予了对盐胁迫和干旱的耐受性，维持了生理和形态表现，可用于基因工程方法来克服多种作物中的这两种胁迫。
在线版本包含可在10.1007/s12298 - 021 - 00999 - z获取的补充材料。
