β-amylase induction and the protective role of maltose during temperature shock
β-amylase induction and the protective role of maltose during temperature shock
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DOI：
10.1104/pp.104.040808
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发表时间：
2004-07-01
期刊：
影响因子：
7.4
通讯作者：
Guy, CL
中科院分区：
文献类型：
--
作者：
Kaplan, F;Guy, CL
许多研究表明，非生物胁迫可以诱导β-淀粉酶的产生。在本工作中，从45摄氏度到0摄氏度以5摄氏度递增的温度响应图谱表明，在极端温度下的诱导是该基因家族的两个成员(BMY7和BMY8)所特有的。这两个成员都编码具有明显转运肽的蛋白质，用于叶绿体基质定位。然而，对于BMY7和BMY8，没有观察到对温度胁迫有相当特异反应的其他关键淀粉降解酶的诱导。40℃热休克和5℃冷休克的时间进程实验表明，β-淀粉酶的诱导与麦芽糖的积累有关。体外试验表明，麦芽糖在生理浓度下具有保护蛋白质、膜和光合作用电子传输链的能力。因此，β-淀粉酶的诱导和由此产生的麦芽糖积累可能作为叶绿体基质中的亲和溶质稳定因子来响应急性温度胁迫。
A number of studies have demonstrated beta-amylase induction in response to abiotic stress. In the present work, a temperature response profile in 5degreesC increments from 45degreesC to 0degreesC showed that induction at temperature extremes was specific for two members of the gene family (BMY7 and BMY8). Both members encode proteins that possess apparent transit peptides for chloroplast stromal localization. However, induction was not observed for other key starch degrading enzymes demonstrating a rather specific response to temperature stress for BMY7 and BMY8. Time course experiments for heat shock at 40degreesC and cold shock at 5degreesC showed that beta-amylase induction correlated with maltose accumulation. Maltose has the ability, as demonstrated by in vitro assays, to protect proteins, membranes, and the photosynthetic electron transport chain at physiologically relevant concentrations. Therefore, beta-amylase induction and the resultant maltose accumulation may function as a compatible-solute stabilizing factor in the chloroplast stroma in response to acute temperature stress.