c-di-GMP inhibits the DNA binding activity of H-NS in Salmonella.

Autor: Li, Shuyu, Liu, Qinmeng, Duan, Chongyi, Li, Jialin, Sun, Hengxi, Xu, Lei, Yang, Qiao, Wang, Yao, Shen, Xihui, Zhang, Lei
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Zdroj: Nature Communications; 11/18/2023, Vol. 14 Issue 1, p1-11, 11p
Abstrakt: Cyclic di-GMP (c-di-GMP) is a second messenger that transduces extracellular stimuli into cellular responses and regulates various biological processes in bacteria. H-NS is a global regulatory protein that represses expression of many genes, but how H-NS activity is modulated by environmental signals remains largely unclear. Here, we show that high intracellular c-di-GMP levels, induced by environmental cues, relieve H-NS-mediated transcriptional silencing in Salmonella enterica serovar Typhimurium. We find that c-di-GMP binds to the H-NS protein to inhibit its binding to DNA, thus derepressing genes silenced by H-NS. However, c-di-GMP is unable to displace H-NS from DNA. In addition, a K107A mutation in H-NS abolishes response to c-di-GMP but leaves its DNA binding activity unaffected in vivo. Our results thus suggest a mechanism by which H-NS acts as an environment-sensing regulator in Gram-negative bacteria. H-NS is a global regulatory protein that represses expression of many genes in bacteria. Here, Li et al. show that a second messenger, cyclic di-GMP, binds to H-NS and inhibits its binding to DNA, thus relieving H-NS-mediated transcriptional silencing. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
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