Department of Biochemistry, Robert Wood Johnson Medical School, UMDNJ, CABM, Piscataway, NJ, USA.
RNA Biol. 2010 Nov-Dec;7(6):788-95. doi: 10.4161/rna.7.6.13482. Epub 2010 Nov 1.
One of the many important consequences that temperature down-shift has on cells is stabilization of secondary structures of RNAs. This stabilization has wide-spread effects, such as inhibition of expression of several genes due to termination of their transcription and inefficient RNA degradation that adversely affect cell growth at low temperature. Several cold shock proteins are produced to counteract these effects and thus allow cold acclimatization of the cell. The main RNA modulating cold shock proteins of E. coli can be broadly divided into two categories, (1) the CspA family proteins, which mainly affect the transcription and possibly translation at low temperature through their RNA chaperoning function and (2) RNA helicases and exoribonucleases that stimulate RNA degradation at low temperature through their RNA unwinding activity.
温度下降对细胞的众多重要影响之一是稳定 RNA 的二级结构。这种稳定具有广泛的影响,例如由于转录终止和低效 RNA 降解而抑制几个基因的表达,这会对低温下的细胞生长产生不利影响。产生了几种冷休克蛋白来对抗这些影响,从而使细胞能够适应低温。大肠杆菌中主要的 RNA 调节冷休克蛋白可大致分为两类,(1)CspA 家族蛋白,它们主要通过 RNA 伴侣功能影响低温下的转录和翻译,以及(2)RNA 解旋酶和核酸外切酶,它们通过 RNA 解链活性在低温下刺激 RNA 降解。