NaCl enhances cellular cAMP and upregulates genes related to heterocyst development in the cyanobacterium, Anabaena sp. strain PCC 7120.
Cellular cAMP was rapidly increased in the nitrogen-fixing cyanobacterium, Anabaena sp. PCC 7120, by the addition of 200 mM NaCl to the culture medium. Other alkaline-metal chlorides such as KCl or LiCl caused a lesser increase. The increase in cellular cAMP was transient and diminished when an adenylate cyclase, CyaC, which contains the conserved domains of the bacterial two-component regulatory system, was disrupted. DNA microarray analysis showed that expression of a gene cluster containing all5347 and alr5351 (hglE) was upregulated by NaCl in the wild-type strain but not in the cyaC mutant. Primer extension analysis indicated that transcription levels of all5347 and hglE were rapidly increased in response to the NaCl addition, and that these genes have NaCl-dependent transcription start sites. It was concluded that NaCl induced expression of genes related to heterocyst envelope formation in this cyanobacterium, possibly via a CyaC-cAMP signal transduction system.
Imashimizu
Masahiko
M
Department of Life Sciences, The University of Tokyo, 381 Komaba, Meguro, Tokyo 153-8902, Japan.
Yoshimura
Hidehisa
H
Katoh
Hiroshi
H
Ehira
Shigeki
S
Ohmori
Masayuki
M
D017033:Anabaena / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003470:Culture Media; D000242:Cyclic AMP / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D015398:Signal Transduction; D012965:Sodium Chloride / Q000494:pharmacology*; D015854:Up-Regulation
D001426:Bacterial Proteins; D003470:Culture Media; D012965:Sodium Chloride; D000242:Cyclic AMP