Abstract

Cold stress affects plant growth and crop productivity. Consequently, there is considerable interest in plant genes that respond to cold stress as these might provide a better understanding of the mechanisms of chilling tolerance. In the present study, S-adenosylmethionine synthetase (SAMS), a cold-responsive gene isolated from Miscanthus sinensis Andersson, was transformed into Nicotiana benthamiana Domin to investigate its function under low temperature stress. The levels of MsSAMS transcripts increased over a 48 h period in response to cold treatment and increased cold tolerance in the transgenic plants. The change in cold tolerance was confirmed by determining the recovery rate of the plants and by measurement of ion leakage after cold treatment. The morphological characteristics of transgenic plants overexpressing MsSAMS were investigated by transmission electron microscopy. Based on this morphological analysis, transgenic plants exhibited an increase in cell wall thickness compared to control plants. We conclude that MsSAMS is involved in the mechanism of cold tolerance in tobacco, as evidenced by the phenotypes of the transgenic plants.

中文翻译：

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S-腺苷甲硫氨酸合成酶的过表达增强了烟草对冷胁迫的耐受性

摘要

冷胁迫影响植物的生长和作物的生产力。因此，人们对响应冷胁迫的植物基因非常感兴趣，因为它们可以更好地理解耐寒性的机制。在本研究中，S-腺苷甲硫氨酸合成酶（SAMS）是一种从中华芒（Miscanthus sinensis Andersson）中分离出来的冷应答基因，被转化为烟草（Nicotiana benthamiana Domin）以研究其在低温胁迫下的功能。MsSAMS的级别响应冷处理，转录本在48小时内增加，转基因植物的耐冷性增加。通过确定植物的恢复率并通过测量冷处理后的离子泄漏来确认耐寒性的变化。通过透射电子显微镜研究了过表达MsSAMS的转基因植物的形态特征。基于这种形态分析，与对照植物相比，转基因植物的细胞壁厚度增加。我们得出的结论是，MsSAMS参与了烟草的耐冷性机制，如转基因植物的表型所证明。