Sato Shinichiro, Ikeuchi Masahiko, Nakamoto Hitoshi
Department of Biochemistry and Molecular Biology, Saitama University, Saitama 338-8570, Japan.
FEBS Lett. 2008 Oct 15;582(23-24):3389-95. doi: 10.1016/j.febslet.2008.08.034. Epub 2008 Sep 9.
Cyanobacterial genomes generally contain two groEL genes, referred to as groEL1 and groEL2. The purpose of this study is to elucidate a role of groEL2 in the adaptation of the thermophilic cyanobacterium Thermosynechococcuselongatus to hot environments. Both groEL genes were found to be heat-induced, while only groEL2 was greatly cold-induced. Primer extension and gel mobility shift analyses indicated that transcriptional regulation of groEL2 is different from that of groESL1. The groEL2 gene was dispensable under normal growth conditions at 50 degrees C as a groEL2 disruptant was viable. This groEL2 mutant was highly sensitive to both high and low temperatures.
蓝藻基因组通常包含两个groEL基因，分别称为groEL1和groEL2。本研究的目的是阐明groEL2在嗜热蓝藻嗜热栖热放线菌适应高温环境中的作用。发现这两个groEL基因均受热诱导，而只有groEL2受强烈冷诱导。引物延伸和凝胶迁移率变动分析表明，groEL2的转录调控与groESL1不同。在50摄氏度的正常生长条件下，groEL2基因是可有可无的，因为groEL2缺失突变体是可存活的。这个groEL2突变体对高温和低温都高度敏感。
