Project description:Host-pathogen interactions in Mycobacterium tuberculosis infection still remain poorly understood. We investigated the host immune response to different reference Mycobacterium tuberculosis strains in THP-1 cells. Major differences in the gene expression profiles were identified in response to infection with these strains. These findings shed new insights into the dynamic variation in tuberculosis immune response and pathogenesis. We used Affymetrix GeneChip Human Exon 1.0 ST microarrays to investigate host differential gene expression in response to different Mycobacterium tuberculosis strains.
Project description:①Background:Tuberculosis is mainly a respiratory tract infection caused by mycobacterium tuberculosis and one of the leading causes of death worldwide. According to the Global Tuberculosis Report in 2021, About a quarter of the world's population is infected with Mycobacterium tuberculosis and China is the second highest burden of TB. Although TB diagnosis and prevention techniques have become more mature, the number of TB cases is still increasing, mainly due to: the prevalence of drug-resistant tuberculosis bacteria, tuberculosis and HIV co-infection, long incubation time of mycobacterium tuberculosis difficult to early diagnosis and so on. Therefore, it is of great significance to study the pathogenesis of mycobacterium tuberculosis infection.②Method: THP-1 cells were treated with 50ng/ml PMA for 24 hours, so that THP-1 cell can be induced into macrophages. After that THP-1 macrophages were infected with mycobacterium tuberculosis H37Rv(MOI=1), which were collected and applied to RNA-sequencing. The constructed sequencing library was sequenced using an Illumina Novaseq 6000 system.
Project description:Transcriptional changes during early infection of macrophage-like THP-1 cell line with pathogenic bacterium Mycobacterium tuberculosis. RNAseq samples were taken at 0h (THP-1 cells growing in the RPMI medium), and after 4h, 24h and 48h post infection. Bacterial enrichment was performed to increase the amount of bacterial mRNA in the samples. Non-enriched samples were used to map THP-1 cells transcripts; enriched samples were used to map M. tuberculosis transcripts the corresponding genomes.
Project description:Transcriptional response of THP-1 cells infected with Mycobacterium tuberculosis utilizing ‘Active’ Mtb and ‘Dormant’ Mtb infection models at different time points. Analysis of the transcriptomic data deciphered the perturbation of gamut of host cellular pathways that are common and differentially manifested in the ‘Active’ Mtb and ‘Dormant’ Mtb infection models.
Project description:Rationale: Tuberculosis has a devastating impact on global health by claiming nearly 1.4 million lives each year. During infection Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, produces heterogenous populations some of which don’t produce colonies on agar but grow in liquid media and often require supplementation with culture supernatants or recombinant Resuscitation-promoting factor, thus defined as differentially culturable bacilli. Objectives: to evaluate whether exposure to nitric oxide (NO), a well-known host defence molecule, alters mycobacterial growth phenotypes and drives generation of Rpf-dependent differentially culturable bacilli. Methods: a novel NO donor was synthesised and tested against Mtb and Mycobacterium bovis BCG in vitro, followed by growth assays, flow cytometry analysis and assessment of transcriptomic responses. Resuscitation-promoting factor (Rpf) inhibitors were used to characterise the role of Rpf proteins in the reactivation of NO-treated mycobacteria. Mycobacterial phenotypes were also investigated during infection of THP-1 macrophages activated with retinoic acid and vitamin D3. Measurements and Main Results: differentially culturable mycobacteria were generated after exposure to the novel NO donor or during infection of activated THP-1 cells. Resuscitation of these differentially culturable bacilli was largely abolished by specific Rpf inhibitors. Transcriptomic analysis revealed redox-associated stress signatures mediated by SigH and SigF, with significant down-regulation of ribosome and cell wall architecture genes, including rpfA, rpfB and rpfE, and induction of genes involved in response to thiol stress, sulphur metabolism and iron acquisition. Conclusion: Our study provides mechanistic insights into the generation of Rpf-dependent Mtb during tuberculosis and outlines a critical role of NO in this process.
Project description:The liver of dairy cows naturally displays a series of metabolic adaptation during the periparturient period in response to the increasing nutrient requirement of lactation. The hepatic adaptation is partly regulated by insulin resistance and it is affected by the prepartal energy intake level of cows. We aimed to investigate the metabolic changes in the liver of dairy cows during the periparturient at gene expression level and to study the effect of prepartal energy level on the metabolic adaptation at gene expression level.B13:N13
Project description:The Toll-like receptor (TLR) and peptidoglycan recognition protein 1 (PGLYRP1) genes play key roles in the innate immune systems of mammals. While the TLRs recognize a variety of invading pathogens and induce innate immune responses, PGLYRP1 is directly microbicidal. We used custom allele-specific assays to genotype and validate 220 diallelic variants, including 54 nonsynonymous SNPs in 11 bovine innate immune genes (TLR1-TLR10, PGLYRP1) for 37 cattle breeds. Bayesian haplotype reconstructions and median joining networks revealed haplotype sharing between Bos taurus taurus and Bos taurus indicus breeds at every locus, and we were unable to differentiate between the specialized B. t. taurus beef and dairy breeds, despite an average polymorphism density of one locus per 219 bp. Ninety-nine tagSNPs and one tag insertion-deletion polymorphism were sufficient to predict 100% of the variation at all 11 innate immune loci in both subspecies and their hybrids, whereas 58 tagSNPs captured 100% of the variation at 172 loci in B. t. taurus. PolyPhen and SIFT analyses of nonsynonymous SNPs encoding amino acid replacements indicated that the majority of these substitutions were benign, but up to 31% were expected to potentially impact protein function. Several diversity-based tests provided support for strong purifying selection acting on TLR10 in B. t. taurus cattle. These results will broadly impact efforts related to bovine translational genomics.
Project description:BackgroundWe present here the assembly of the bovine genome. The assembly method combines the BAC plus WGS local assembly used for the rat and sea urchin with the whole genome shotgun (WGS) only assembly used for many other animal genomes including the rhesus macaque.ResultsThe assembly process consisted of multiple phases: First, BACs were assembled with BAC generated sequence, then subsequently in combination with the individual overlapping WGS reads. Different assembly parameters were tested to separately optimize the performance for each BAC assembly of the BAC and WGS reads. In parallel, a second assembly was produced using only the WGS sequences and a global whole genome assembly method. The two assemblies were combined to create a more complete genome representation that retained the high quality BAC-based local assembly information, but with gaps between BACs filled in with the WGS-only assembly. Finally, the entire assembly was placed on chromosomes using the available map information.Over 90% of the assembly is now placed on chromosomes. The estimated genome size is 2.87 Gb which represents a high degree of completeness, with 95% of the available EST sequences found in assembled contigs. The quality of the assembly was evaluated by comparison to 73 finished BACs, where the draft assembly covers between 92.5 and 100% (average 98.5%) of the finished BACs. The assembly contigs and scaffolds align linearly to the finished BACs, suggesting that misassemblies are rare. Genotyping and genetic mapping of 17,482 SNPs revealed that more than 99.2% were correctly positioned within the Btau_4.0 assembly, confirming the accuracy of the assembly.ConclusionThe biological analysis of this bovine genome assembly is being published, and the sequence data is available to support future bovine research.
Project description:Perturbation of host physiology by intracellular Mycobacterium tuberculosis (H37Rv) can be reflected by changes in gene expression pattern of host genes. Total RNA was isolated from PMA differentiated uninfected cells or cells infected with H37Rv for 16, 48 or 90 hours and gene expression profile was obtained. There are in all 8 samples, two replcates of each 4. Two samples, namely 1D,1E (replicates of one) are control (PMA differentiated Thp-1 cells Uninfected controls). Cells were infected with H37Rv at an MOI of 1:10 and samples were collected at 16 hours, 48 hours and 90 hours post-infection.