Abstract

The role of the protein synthesis system in the physiological responses to cold was assessed in chilling-sensitive (cucumber) and cold-tolerant (wheat) plants with the use of protein-synthesis inhibitors on 80S (cycloheximide, CHX) and 70S (chloramphenicol, CAP) ribosomes. The plants were subjected to a constant low temperature (LT treatment) at 12°C for cucumber and 4°C for wheat. Another regimen (DROP treatment) included a 2-h daily temperature drop to 12°C for cucumber and 4°C for wheat at the end of the night. Both inhibitors were found to suppress plant leaf growth under any temperature regimen, including the control (at a constant temperature of 23°C). They also reduced the rates of net photosynthesis, transpiration, dark respiration, and chlorophyll accumulation in all treatments but to a larger degree in the control and DROP-treated plants. The results confirmed the previously established dependence of enhanced cold tolerance on protein biosynthesis on 70S and, especially, 80S ribosomes in the LT-treated plants. It was demonstrated for the first time that the protein synthesis system is involved in the enhancement of plant cold tolerance afforded by short-term daily temperature drops. Temperature drops often occur under natural conditions and are used to reduce stem elongation in greenhouse production as an alternative to the use of retardants. The reported data are novel in that the enhanced cold tolerance of DROP-treated plants is accounted for not only by de novo protein synthesis but also by adaptive posttranslational control.

中文翻译：

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在蛋白质合成抑制剂存在下对低温长期和短期暴露的植物生理响应的比较研究

摘要

使用对80S（cycloheximide，CHX）和70S（氯霉素， CAP）核糖体。使植物在12℃下对黄瓜和在4℃下对小麦进行恒定的低温（LT处理）。另一种方案（DROP处理）包括在夜间结束时每天2小时将黄瓜温度降至12°C，将小麦温度降至4°C。发现这两种抑制剂都可以在任何温度范围内（包括对照）（在23°C的恒定温度下）抑制植物叶片的生长。在所有处理中，它们还降低了净光合作用，蒸腾作用，暗呼吸和叶绿素积累的速率，但在对照和经DROP处理的植物中，其降低幅度更大。结果证实了先前确定的增强的耐冷性对LT处理过的植物中70S尤其是80S核糖体蛋白质生物合成的依赖性。首次证明了蛋白质合成系统参与短期每日温度下降所带来的植物抗寒性的增强。温度下降通常在自然条件下发生，并用于减少温室生产中的茎伸长，以代替使用阻燃剂。报道的数据是新颖的，因为用DROP处理的植物增强的耐寒性不仅是由 首次证明了蛋白质合成系统参与短期每日温度下降所带来的植物抗寒性的增强。温度下降通常在自然条件下发生，并用于减少温室生产中的茎伸长，以代替使用阻燃剂。报道的数据是新颖的，因为用DROP处理的植物增强的耐寒性不仅是由 首次证明了蛋白质合成系统参与短期每日温度下降所带来的植物抗寒性的增强。温度下降通常在自然条件下发生，并用于减少温室生产中的茎伸长，以代替使用阻燃剂。报道的数据是新颖的，因为用DROP处理的植物增强的耐寒性不仅是由从头合成蛋白质，也可以通过自适应翻译后控制。