ArticleJournal of bacteriology2001
Identification and inactivation of three group 2 sigma factor genes in Anabaena sp. strain PCC 7120.
Article in Journal of bacteriology, 2001. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers.
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Who cites it
21 citing papers in PubMed.
- Coordination of NProceedings of the National Academy of Sciences of the United States of America · 2026Article
- The small CaBMC microbiology · 2020Article
- The influence of sigma factors and ribosomal recognition elements on heterologous expression of cyanobacterial gene clusters in Escherichia coli.FEMS microbiology letters · 2018Article
- Calcium impacts carbon and nitrogen balance in the filamentous cyanobacterium Anabaena sp. PCC 7120.Journal of experimental botany · 2016Article
- Regulation of Genes Involved in Heterocyst Differentiation in the Cyanobacterium Anabaena sp. Strain PCC 7120 by a Group 2 Sigma Factor SigC.Life (Basel, Switzerland) · 2015Article
- Engineered transcriptional systems for cyanobacterial biotechnology.Frontiers in bioengineering and biotechnology · 2014Review
- Overexpression of pknE blocks heterocyst development in Anabaena sp. strain PCC 7120.Journal of bacteriology · 2011Article
- The sigE gene is required for normal expression of heterocyst-specific genes in Anabaena sp. strain PCC 7120.Journal of bacteriology · 2011Article
- Effects of deficiency and overdose of group 2 sigma factors in triple inactivation strains of Synechocystis sp. strain PCC 6803.Journal of bacteriology · 2011Article
- Cyanobacterial heterocysts.Cold Spring Harbor perspectives in biology · 2010Review
- Sigma factors for cyanobacterial transcription.Gene regulation and systems biology · 2009Article
- Regulation of fructose transport and its effect on fructose toxicity in Anabaena spp.Journal of bacteriology · 2008Article
- Transcription activation by NtcA and 2-oxoglutarate of three genes involved in heterocyst differentiation in the cyanobacterium Anabaena sp. strain PCC 7120.Journal of bacteriology · 2008Article
- Characterization of single and double inactivation strains reveals new physiological roles for group 2 sigma factors in the cyanobacterium Synechocystis sp. PCC 6803.Plant physiology · 2008Article
- Sigma factor genes sigC, sigE, and sigG are upregulated in heterocysts of the cyanobacterium Anabaena sp. strain PCC 7120.Journal of bacteriology · 2007Article
- Group 3 sigma factor gene, sigJ, a key regulator of desiccation tolerance, regulates the synthesis of extracellular polysaccharide in cyanobacterium Anabaena sp. strain PCC 7120.DNA research : an international journal for rapid publication of reports on genes and genomes · 2007Article
- Signal transduction genes required for heterocyst maturation in Anabaena sp. strain PCC 7120.Journal of bacteriology · 2006Article
- The genome of S-PM2, a "photosynthetic" T4-type bacteriophage that infects marine Synechococcus strains.Journal of bacteriology · 2005Article
- Different functions of HetR, a master regulator of heterocyst differentiation in Anabaena sp. PCC 7120, can be separated by mutation.Proceedings of the National Academy of Sciences of the United States of America · 2004Article
- Expression of primary sigma factor (PSF) and PSF-like sigma factors in the cyanobacterium Synechocystis sp. strain PCC 6803.Journal of bacteriology · 2003Article
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2 authors.
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Abstract
Three new Anabaena sp. strain PCC 7120 genes encoding group 2 alternative sigma factors have been cloned and characterized. Insertional inactivation of sigD, sigE, and sigF genes did not affect growth on nitrate under standard laboratory conditions but did transiently impair the abilities of sigD and sigE mutant strains to establish diazotrophic growth. A sigD sigE double mutant, though proficient in growth on nitrate and still able to differentiate into distinct proheterocysts, was unable to grow diazotrophically due to extensive fragmentation of filaments upon nitrogen deprivation. This double mutant could be complemented by wild-type copies of sigD or sigE, indicating some degree of functional redundancy that can partially mask phenotypes of single gene mutants. However, the sigE gene was required for lysogenic development of the temperate cyanophage A-4L. Several other combinations of double mutations, especially sigE sigF, caused a transient defect in establishing diazotrophic growth, manifested as a strong and prolonged bleaching response to nitrogen deprivation. We found no evidence for developmental regulation of the sigma factor genes. luxAB reporter fusions with sigD, sigE, and sigF all showed slightly reduced expression after induction of heterocyst development by nitrogen stepdown. Phylogenetic analysis of cyanobacterial group 2 sigma factor sequences revealed that they fall into several subgroups. Three morphologically and physiologically distant strains, Anabaena sp. strain PCC 7120, Synechococcus sp. strain PCC 7002, and Synechocystis sp. strain PCC 6803 each contain representatives of four subgroups. Unlike unicellular strains, Anabaena sp. strain PCC 7120 has three additional group 2 sigma factors that cluster in subgroup 2.5b, which is perhaps specific for filamentous or heterocystous cyanobacteria.
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