Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-0032 Japan.
Plant Cell Physiol. 2011 Feb;52(2):404-12. doi: 10.1093/pcp/pcq204. Epub 2011 Jan 6.
Sugar catabolic genes are induced during nitrogen starvation in a cyanobacterium Synechocystis sp. PCC 6803, but the underlying regulatory mechanism still remains to be completely characterized. In this study, we showed by molecular genetics and transcriptome analyses that a response regulator Rre37 (encoded by sll1330), whose expression is enhanced by nitrogen depletion under the control of NtcA, activates transcript accumulation of sugar catabolic genes, such as gap1, pfkA (sll1196), glgP (slr1367) and glgX (slr1857), mainly during nitrogen starvation. Previously, we reported that a group-2 sigma factor SigE also positively regulates sugar catabolic genes in this strain. Phenotypic analyses using a single or double mutant lacking rre37 and/or sigE indicated that both SigE and Rre37 positively regulate sugar catabolic genes independently. These findings substantiated a regulatory network of sugar catabolic genes in this cyanobacterium.
在蓝藻集胞藻 PCC 6803 中，糖代谢基因在氮饥饿时被诱导，但潜在的调控机制仍有待完全阐明。在这项研究中，我们通过分子遗传学和转录组分析表明，应答调节因子 Rre37（由 sll1330 编码），其表达受 NtcA 控制，在氮饥饿下增强，激活糖分解代谢基因，如 gap1、pfkA（sll1196）、glgP（slr1367）和 glgX（slr1857）的转录积累，主要在氮饥饿期间。此前，我们报道了一个组 2σ因子 SigE 也正向调节该菌株中的糖分解代谢基因。使用缺失 rre37 和/或 sigE 的单个或双突变体进行表型分析表明，SigE 和 Rre37 独立地正向调节糖分解代谢基因。这些发现证实了该蓝藻中糖分解代谢基因的调控网络。
