NtcA represses transcription of gifA and gifB, genes that encode inhibitors of glutamine synthetase type I from Synechocystis sp. PCC 6803

@article{GarcaDomnguez2000NtcART,
  title={NtcA represses transcription of gifA and gifB, genes that encode inhibitors of glutamine synthetase type I from Synechocystis sp. PCC 6803},
  author={Mario Garc{\'i}a-Dom{\'i}nguez and Jos{\'e} C. Reyes and Francisco J. Florencio},
  journal={Molecular Microbiology},
  year={2000},
  volume={35}
}
Synechocystis sp. PCC 6803 glutamine synthetase type I (GS) activity is controlled by direct interaction with two inactivating factors (IF7 and IF17). IF7 and IF17 are homologous polypeptides encoded by the gifA and gifB genes respectively. We investigated the transcriptional regulation of these genes. Expression of both genes is maximum in the presence of ammonium, when GS is inactivated. Nitrogen starvation attenuates the ammonium‐mediated induction of gifA and gifB as well as the ammonium… 
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
It is shown that expression of both the glnA and glnN genes is subjected to transcriptional regulation in response to changes in nitrogen availability, and that an additional modification of NtcA or an additional factor is required for the regulation of glnnN gene expression.
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TLDR
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TLDR
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TLDR
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TLDR
The gene ntcA is proposed to encode a transcriptional activator of genes subject to nitrogen control in Synechococcus, and of special biological significance, is the presence of a conserved helix‐turn‐helix motif in the sequence close to the C‐terminal end of all the proteins in the family.
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TLDR
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TLDR
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A DNA-binding factor (VF1) partially purified from Anabaena sp. strain PCC 7120 vegetative cell extracts by heparin-Sepharose chromatography was found to have affinity for the xisA upstream region.
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