Project description:To investigate the function of All0854, we constructed the all0854 deletion mutant Mall0854, in which all0854 was knocked out by CRISPER-cpf1. We then performed gene expression profiling analysis using data obtained from RNA-seq of wide type Nostoc sp. PCC 7120 and Mall0854.
Project description:Proteogenomics analysis was employed to refine the genome annotation and provide new insights into nitrogen metabolism of Nostoc sp. PCC 7120.
Project description:Identification of the global transcriptional regulator All3953 (RbcR) in the cyanobacterium Anabaena sp. PCC 7120 by ChIP-Seq analysis
Project description:Transcriptomic analyses using high-throughput methods have revealed abundant antisense transcription in bacteria. Most frequently, antisense transcription is due to the overlap of mRNAs with long 5’ regions or 3’ ends that extend beyond the coding sequence. In addition, antisense RNAs that do not contain any coding sequence are also observed. Nostoc sp. PCC 7120 is a filamentous cyanobacterium that, under nitrogen limitation, behaves as a multicellular organism with division of labor among two different cell types that depend on each other, the vegetative CO2-fixing cells and the nitrogen-fixing heterocysts. Differentiation of heterocysts depends on the global nitrogen regulator NtcA and requires the specific regulator HetR. To identify antisense RNAs potentially involved in heterocyst differentiation we performed an RNA-Seq analysis of cells subjected to nitrogen limitation (either at 9 or 24 hours after nitrogen removal) and analyzed the results in combination with a genome-wide set of nitrogen-regulated transcriptional start sites and a prediction of transcriptional terminators. Our analysis resulted in the definition of a transcriptional map including more than 4,000 transcripts, 65% of them in antisense orientation to other transcripts. In addition to overlapping mRNAs we identified nitrogen-regulated non-coding antisense RNAs transcribed from NtcA-dependent or HetR-dependent promoters.
