ArticleJournal of bacteriology2011
The sigE gene is required for normal expression of heterocyst-specific genes in Anabaena sp. strain PCC 7120.
Article in Journal of bacteriology, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 35 citations in OpenAlex.
- Coordination of NProceedings of the National Academy of Sciences of the United States of America · 2026Article
- Predicting FOX gene candidates for oxic nitrogen fixation using multi-omic machine learning and comparative bioinformatics.Scientific reports · 2026Article
- Article
- R-DeeP/TripepSVM identifies the RNA-binding OB-fold-like protein PatR as regulator of heterocyst patterning.Nucleic acids research · 2025Article
- The modular architecture of sigma factors in cyanobacteria: a framework to assess their diversity and understand their evolution.BMC genomics · 2024Article
- Spatio-temporal coherence of circadian clocks and temporal control of differentiation inmSystems · 2024Article
- Cross-Activation of Two Nitrogenase Gene Clusters by CnfR1 or CnfR2 in the Cyanobacterium Anabaena variabilis.Microbiology spectrum · 2021Article
- The influence of sigma factors and ribosomal recognition elements on heterologous expression of cyanobacterial gene clusters in Escherichia coli.FEMS microbiology letters · 2018Article
- Role of RNA secondary structure and processing in stability of the nifH1 transcript in the cyanobacterium Anabaena variabilis.Journal of bacteriology · 2015Article
- 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
- Regulation of Three Nitrogenase Gene Clusters in the Cyanobacterium Anabaena variabilis ATCC 29413.Life (Basel, Switzerland) · 2014Review
- Regulation of nitrogenase gene expression by transcript stability in the cyanobacterium Anabaena variabilis.Journal of bacteriology · 2014Article
- Secondary metabolite gene expression and interplay of bacterial functions in a tropical freshwater cyanobacterial bloom.The ISME journal · 2014Article
- NrrA, a nitrogen-regulated response regulator protein, controls glycogen catabolism in the nitrogen-fixing cyanobacterium Anabaena sp. strain PCC 7120.The Journal of biological chemistry · 2011Article
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5 authors at 2 institutions in 1 country.
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No grant is acknowledged in the PubMed record.
Abstract
The filamentous cyanobacterium Anabaena (Nostoc) sp. strain PCC 7120 produces specialized cells for nitrogen fixation called heterocysts. Previous work showed that the group 2 sigma factor sigE (alr4249; previously called sigF) is upregulated in differentiating heterocysts 16 h after nitrogen step-down. We now show that the sigE gene is required for normal heterocyst development and normal expression levels of several heterocyst-specific genes. Mobility shift assays showed that the transcription factor NtcA binds to sites in the upstream region of sigE and that this binding is enhanced by 2-oxoglutarate (2-OG). Deletions of the region containing the NtcA binding sites in P(sigE)-gfp reporter plasmids showed that the sites contribute to normal developmental regulation but are not essential for upregulation in heterocysts. Northern RNA blot analysis of nifH mRNA revealed delayed and reduced transcript levels during heterocyst differentiation in a sigE mutant background. Quantitative reverse transcription-PCR (qRT-PCR) analyses of the sigE mutant showed lower levels of transcripts for nifH, fdxH, and hglE2 but normal levels for hupL. We developed a P(nifHD)-gfp reporter construct that showed strong heterocyst-specific expression. Time-lapse microscopy of the P(nifHD)-gfp reporter in a sigE mutant background showed delayed development and undetectable green fluorescent protein (GFP) fluorescence. Overexpression of sigE caused accelerated heterocyst development, an increased heterocyst frequency, and premature expression of GFP fluorescence from the P(nifHD)-gfp reporter.
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