Abstract
In Synechocystis sp. PCC 6803, genes for sugar catabolism such as glycolysis, glycogen catabolism and oxidative pentose pathway were induced during nitrogen starvation. Recently, we found that sigma factor SigE was induced under nitrogen starvation in an NtcA-dependent manner and positively regulated expression of sugar catabolic genes (Osanai et al., 2006). Here, we show a response regulator rre37 also participates in regulation of sugar catabolism.
Expression of Rre37 was induced dependent on NtcA under nitrogen depletion. Microarray analysis clarified the expression of sugar catabolic genes, gap1 (slr0884), pfkA (sll1196), glgX (slr1857) and glgP (slr1367), were decreased by rre37 disruption. Since these genes were also included in the SigE regulon, we performed Northern and Western analysis using single or double mutant lacking rre37 and/or sigE to investigate the relationship between Rre37 and SigE. The results suggested that both Rre37 and SigE regulated sugar catabolic genes, and these regulations could function independently.
