Terauchi Kazuki, Ohmori Masayuki
Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan.
Mol Microbiol. 2004 Apr;52(1):303-9. doi: 10.1111/j.1365-2958.2003.03980.x.
The participation of cAMP in photosignal transduction in cyanobacteria was investigated. When cells of the cyanobacterium Synechocystis sp. PCC 6803 were exposed to light, cellular cAMP contents increased within a few minutes. Among incident monochromatic lights, blue light (450 nm) markedly increased cellular cAMP content, while red (630 nm) and far-red (720 nm) lights did not. Disruption of the cya1 gene encoding an adenylate cyclase caused the insensitivity of cellular cAMP level to blue light. Treatment of wild-type cells with the flavin antagonist phenylacetic acid inhibited this blue light effect. The motility of wild-type cells was enhanced by blue light, whereas that of cya1 mutant cells was not. Based on these results, we concluded that a blue light-cAMP signal transduction system stimulates the motility of Synechocystis sp. PCC 6803.
研究了环磷酸腺苷（cAMP）在蓝藻光合信号转导中的参与情况。当蓝藻集胞藻PCC 6803的细胞暴露于光照下时，细胞内的cAMP含量在几分钟内就会增加。在入射的单色光中，蓝光（450纳米）显著增加细胞内的cAMP含量，而红光（630纳米）和远红光（720纳米）则没有。编码腺苷酸环化酶的cya1基因的破坏导致细胞cAMP水平对蓝光不敏感。用黄素拮抗剂苯乙酸处理野生型细胞可抑制这种蓝光效应。蓝光增强了野生型细胞的运动性，而cya1突变细胞则没有。基于这些结果，我们得出结论，蓝光 - cAMP信号转导系统刺激了集胞藻PCC 6803的运动性。
