Project description:Nowadays proteomics is the one of the major instruments for editing and correct decryption of genomic information. Genomic correction of socially significant pathogens, like Mycobacterium tuberculosis, is by far the most relevant. We conducted proteogenomic analysis of W-148 strain, which belong to the Beijing B0/W148 cluster. Strains of this cluster possess unique pathogenic properties and have a unique genome organization. Taking into account a high similarity of cluster strains at the genomic level we analysed MS/MS datasets obtained for 63 clinical isolates of Beijing B0/W148. Based on H37Rv and W-148 annotations we identified 2,546 proteins, representing more than 60 % of total proteome. A set of peptides (n=404), specific for W-148 was found in comparison with H37Rv. Start sites for 32 genes were corrected based on combination of LC-MS/MS proteomic data with genomic six frame translation. Additionally, presence of peptides for 10 pseudogenes has been confirmed. Thus, the data obtained by us undoubtedly shows the need for conducting genome annotation based on proteomic data. Corrected during the study W-148 genome annotation will allow to use it in studies on Beijing B0/W148 cluster strains.
Project description:Mycobacterium tuberculosis Beijing B0/W148 is one of the most widely distributed clusters in the Russian Federation and in some countries of the former Soviet Union. Recent studies have improved our understanding of the reasons for the “success” of the cluster but this area remains incompletely studied. Here, we focused on the system omics analysis of the RUS_B0 strain belonging to the Beijing B0/W148 cluster. Completed genome sequence of RUS_B0 (CP020093.1) and a collection of WGS for 200 cluster strains from the NCBI were used to describe the main genetic features of the population, as well as the level of resistance. In turn, proteome and transcriptome studies allowed to confirm the genomic data and to identify a number of finds that have not previously been described. Our results demonstrate that expression of the whiB6 which contains cluster-specific polymorphism (T4338371G) increased by more than 50 times in RUS_B0. Additionally, the level of ethA transcripts in RUS_B0 is increased almost 30 times compared to the H37Rv. Start sites for 10 genes were corrected based on the combination of proteomic and transcriptomic data. Additionally, based on the omics approach, we identified 5 new genes.
Project description:In order to control transposable element (TE) activity, PIWI-interacting RNAs (piRNAs) have been evolved to silence TE transcriptionally and post-transcriptionally, and produced from heterochromatic genomic loci, called piRNA cluster. Maternal inherited piRNAs transmission is considered as the key step of piRNA cluster maintenance and induction of de nove piRNA cluster formation, however, how the original piRNAs were produced without maternal piRNAs deposition remains unclear. In this paper, we created a repetitive GFP reporter and found a Rhino-dependent piRNA cluster conversion spontaneously occurs to the reporter over generations. Importantly, this conversion is reversible by removal of maternal piRNAs of GFP reporter. Taking advantage of this reversible GFP reporter piRNA cluster, we found that siRNA is able to initiate piRNA cluster formation epigenetically, even when only maternal siRNA presence is capable to do so. Our results suggest the importance of siRNA on initiation of piRNA biogenesis and describe a whole picture of initiation and maintenance of piRNA cluster.
Project description:We have previously shown that transgenic overexpression of the miR-200b/200a/429 cluster prevents mammary tumor development in MTB-IGFIR mice. In this study we evaluated whether the miR-200b/200a/429 cluster could also prevent mammary tumor development from a different oncogene, namely Neu/Erbb2. We found that transgenic overexpression of Neu/Erbb2 in MTB-TAN mice induce rapid mammary tumor development and co-overexpression of the miR-200b/200a/429 cluster with Neu/Erbb2 completely prevent mammary epithelial transformation and tumor development
Project description:Comparative genomic hybridizations were performed to compare bont/A1 strains with an A2-like toxin gene cluster organization to the genome sequenced strain, C. botulinum ATCC 3502. Keywords: comparative genomic hybridization