Dual RNA-seq of chlamydial and host cell transcriptomes during nutritional stress
Ontology highlight
ABSTRACT: We utilized host-pathogen dual RNA-sequencing to elucidate the transcriptomes of both Chlamydia trachomatis and the infected HeLa cell during nutritional conditions that induce persistence.
ORGANISM(S): Chlamydia trachomatis L2/434/Bu Homo sapiens
Project description:Chlamydia trachomatis (C. trachomatis) is a major etiological agent of sexually transmitted infection. Some stressing conditions can result in persistent chlamydial infection, which is thought to associate with severe complications such as ectopic pregnancy and tubal factor infertility. Long noncoding RNAs (lncRNAs) have been identified as key modulators in many biological processes. However, the role of lncRNAs in persistent chlamydial infection is still unclear. In this study, we used lncRNA and mRNA microarray to identify the global lncRNAs and mRNAs expression in penicillin-induced persistent chlamydial infection in HeLa cells as well as the control group (HeLa cells without C. trachomatis infection). Among 1005 differentially expressed lncRNAs, 585 lncRNAs were upregulated and 420 downregulated in persistent chlamydial infection, while 410 mRNAs were identified to express differentially, of which 113 mRNAs were upregulated and 297 downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis with differentially expressed genes were performed. We then constructed the lncRNA-miRNA-mRNA competing endogenous RNAs (ceRNAs) network. Four mRNAs were validated to be changed by quantitative real-time PCR which were correlated with the microarray result. Integration of protein-protein interaction (PPI) network was constructed and hub genes were identified. These findings provide a new perspective on the molecular mechanism of penicillin-induced persistent chlamydial infection.
Project description:Chlamydia trachomatis are the etiological agents of a range of diseases and are epidemiologically associated with cervical and ovarian cancers. The interplay between host and chlamydia is highly complex, and to obtain panoramic view of the functional interplay, we performed combinatorial global phosphoproteomic and transcriptomic analyses of C. trachomatis-induced signaling. We identified numerous previously unknown C. trachomatis phosphoproteins and C. trachomatis-regulated host phosphoproteins that are substrates of kinases involved in various cellular processes. Interestingly, several host transcription factors (TFs) that are phosphorylated in C. trachomatis infections, including ETS2 repressor factor (ERF), proto-oncogenic transcription factor ETS1 are targets of ERK MAPK signaling. While these TFs were found to be essential for Chlamydia development, we demonstrated their involvement in inducing epithelial-to-mesenchymal transition in C. trachomatis infected cells by transcriptional regulation of genes involved in cellular motility and invasion. Our data reveals substantially unexplored complexity of C. trachomatis-induced signaling and provides broader insights into pro-carcinogenic potential of C. trachomatis.
Project description:Variations between strains have been extensively studied in human pathogens mainly because even genomically highly identical strains can cause severely different phenotypes in their hosts. Here we investigate within-species diversity in Rhabdochlamydia porcellionis a pathogen infecting terrestrial isopods and a member of the phylum Chlamydia that also includes well-known human pathogens as Chlamydia trachomatis. Using an infection assay in Sf9 insect cell cultures we could show that albeit there are only few genomic variations, the strains 15C and ZGO cause different phenotypes. To investigate potential underlying mechanisms we carried out a global gene expression analysis and could show that changes in major metabolic pathways help strain 15C to replicate more efficiently in the host cells. In addition we found that genes shown to be involved in pathogenicity and host interaction of human pathogenic chlamydia i.e. genes encoding the type III secretion system and polymorphic membrane proteins are regulated differently by the strains.
Project description:Chlamydia trachomatis (C. trachomatis) is an intracellular bacterium, and is one of the main pathogens that cause sexually transmitted infections worldwide. Long non-coding RNAs (lncRNAs) have become vital regulators in many biological processes. However, few studies have shown that lncRNAs take part in the pathogenesis of C. trachomatis. Here, we used microarrays to study the expression profiles of lncRNAs and mRNAs in HeLa cells at 12, 24, and 40 hours pot-infection (hpi). Our study provides evidence that lncRNAs are involved in the interaction between C. trachomatis and hosts.
Project description:Chlamydia trachomatis is a significant human pathogen yet their obligate intracellular nature severe restrictions upon research. Chlamydiae undergo a complex developmental cycle characterized by an infectious cell type known as the elementary body (EB) and an intracellular active replicative form called the reticulate body (RB). EBs have historically been described as metabolically dormant. A cell-free (axenic) culture system was developed which showed high levels of metabolic and biosynthetic activity from both EBs and RBs. EBs preferentially utilized glucose-6-phosphate as an energy source whereas RBs required ATP. Both developmental forms showed improved activity when incubated under microaerobic conditions. Incorporation of isotopically-labeled amino acids into proteins from both developmental forms indicated unique expression profiles which were confirmed by genome-wide transcriptional analysis. The described axenic culture system will greatly enhance biochemical and physiological analyses of chlamydiae. Chlamydia axenic metabolic activity
Project description:In this project we examined the in-vitro effect of female sex hormones (estradiol and progesterone at average physiological concentrations) during a infection mediated by Chlamydia trachomatis serovar D, on the gene expression of human endometrial cell line ECC-1 The effects of the female sex hormones progesterone and oestradiol while infected by Chlamydia trachomatis were examined at two timepoints.
Project description:Chlamydia trachomatis is an obligate intracellular pathogen that replicates within a specialized membrane-bound compartment, the inclusion. Chlamydia species express a unique class of effectors, Incs, which are translocated from the bacteria by a Type III secretion system and are inserted into the inclusion membrane where they modulate the host-bacterium interface. C. trachomatis repositions specific host organelles during infection to acquire nutrients and evade host cell surveillance, however the bacterial and host proteins controlling these processes are largely unknown. Here, we identify an interaction between the host dynactin complex and the C. trachomatis Inc CT192 (CTL0444), hereafter named Dre1 for Dynactin Recruiting Effector 1. We show that dynactin is recruited to the inclusion in a Dre1-dependent manner and that inactivation of Dre1 diminishes the recruitment of specific host organelles, including the centrosome, mitotic spindle, and Golgi Apparatus to the inclusion. Inactivation of Dre1 results in decreased C. trachomatis fitness in cell-based assays and in a mouse model of infection. By targeting particular functions of the versatile host dynactin complex, Dre1 facilitates re-arrangement of certain organelles around the growing inclusion. Our work highlights how C. trachomatis employs a single effector to evoke specific, large-scale changes in host cell organization that establish the intracellular replicative niche without globally inhibiting host cellular function.