Project description:We investigated the impact of on miR-H1 and miR-K12-3-3p- on host transcriptome focusing on gingival epithelial cells that are target sites for various HHV. Results: More than 1300 genes were altered by miR-H1 and miR-K12-3-3p expressing HOK.
Project description:Prevalence of the members of herpesvirus family in oral inflammatory diseases is increasingly acknowledged suggesting their likely role as etiological factor. However, the underlying mechanisms remains obscure. In our recent miRNA profiling of healthy and diseased human tooth pulpal, elevated expression of HHV encoded v-miRs were identified. Based on the fold induction and significance values, we selected three v-miRs namely miR-K12-3-3p (KSHV), miR-H1 (HSV-1), and miR-UL-70-3p (HCMV) to further examine their impact on host cellular functions. We examined their impact on cellular miRNA profiles of primary human oral keratinocytes (HOK). Our results show differential expression of several host miRNAs in v-miR transfected HOK. High levels of v-miRs were detected in exosomes derived from v-miR transfected HOK as well as the latent KSHV infected cell lines. We show that HOK derived exosomes release their contents into macrophages (Mφ) and alter expression of endogenous miRNAs.
Project description:MicroRNAs (miRNAs) are small, non-coding RNAs of ~18-25 nucleotides that have gained extensive attention as critical regulators in complex gene networks including immune cell lineage commitment, differentiation, maturation, and maintenance of immune homeostasis and function. Many viruses encode miRNAs that directly downregulate the expression of factors of the innate immune system, which includes proteins involved in promoting apoptosis and recruitment. In this study, we examined the expression profiles of three previously identified viral miRNAs (v-miRs) from the human herpesvirus (HHV) family, HSV-1 (miR-H1), KSHV (miR-K12-3-3p), and HCMV (miR-US4) in healthy and diseased periodontal tissues and observed increased levels of v-miRs in diseased tissues. To understand the significance of this increase, we overexpressed v-miRs in human oral keratinocytes (HOK), a common target for various HHV, and analyzed the impact of miR-H1 and miR-K12-3-3p on the host transcriptome. More than 1300 genes were altered in HOK overexpressing miR-H1 and miR-K12-3-3p. Global pathway analysis of deregulated genes identified several key cellular pathways that may favor viral persistence. Using bioinformatic analysis, we predicted hundreds of potential v-miR binding sites on genes downregulated by miR-H1 and miR-K12-3-3p and validated three novel target v-miR sites suggesting widespread direct and indirect modulation of numerous host genes/pathways by a single v-miR. Finally, in vitro HSV-1 infection assays showed that miR-H1 can regulate viral entry and infection in human oral keratinocytes (HOK). Overall, our results demonstrate clinical and functional relevance of pathogenic viral molecules viz., v-miRs that regulate both host and viral functions and may contribute to the pathogenesis of inflammatory oral diseases.
Project description:MicroRNAs are 19 to 23 nt RNAs that post-transcriptionally regulate gene expression. Human cells express several hundred miRNAs which regulate important biological pathways such as development, proliferation, and apoptosis. Recently, 12 microRNA genes have been identified within the genome of Kaposiâs sarcoma-associated herpesvirus; however, their functions are still unknown. To identify host cellular genes that may be targeted by these novel viral regulators, we performed gene expression profiling in cells stably expressing KSHV-encoded miRNAs. Data analysis revealed a set of 81 genes whose expression was significantly changed in the presence of miRNAs. While the majority of changes were below 2-fold, eight genes were down-regulated between 4- and 20-fold. We confirmed miRNA-dependent regulation for three of these genes and found that protein levels of thrombospondin 1 (THBS1) were decreased >10-fold. THBS1 has previously been reported to be down-regulated in KS lesions and has known activity as a strong tumor suppressor and anti-angiogenic factor, exerting its anti-angiogenic effect in part by activating the latent form of TGF-b. We show that reduced THBS1 expression in the presence of viral miRNAs translates into decreased TGF-b activity. These data suggest that KSHV-encoded miRNAs may contribute directly to pathogenesis by down-regulation of THBS1, a major regulator of cell adhesion, migration, and angiogenesis. Experiment Overall Design: 293 cells were stably transfected with either a vector expressing 10 KHSV encoded microRNAs or empty vector control. Cells were selected through G418. 4 samples were collected for each cell line and RNA collected for Affymetrix microarray analysis. Results show which transcripts are changed in the presence of KSHV microRNA expression.
Project description:Roseolovirus, or human herpesvirus 6 (HHV-6) is a ubiquitous human pathogen infecting over 95% of the population by the age of two years. As with other herpesviruses, reactivation of HHV-6 can present with severe complications in immunocompromised individuals. Recent studies have highlighted the importance of herpesvirus-derived micro (mi)RNAs in modulating both cellular and viral gene expression. An initial report, which computed the likelihood of various viruses to encode for miRNAs, did not predict HHV-6 miRNAs. To experimentally screen for small HHV-6 encoded RNAs, we conducted large-scale sequencing of Sup-T-1 cells lytically infected with a laboratory strain of HHV-6B. This revealed an abundant 60-65 nucleotide RNA of unknown function derived from the lytic origin of replication (OriLyt) that gave rise to smaller RNA species of 18-19 nucleotides in length. In addition, we identified four pre-miRNAs, whose mature forms accumulated in Argonaute 2. In contrast to other beta-herpesviruses, HHV-6B miRNAs are expressed from direct repeat regions (DRL and DRR) located at either side of the genome. All miRNAs are conserved in the closely related HHV-6A variant, and one of them is a seed ortholog of the human miR-582-5p. Similar to alpha-herpesvirus miRNAs, they are expressed antisense to immediate early ORFs and thus have the potential to regulate key viral regulators. Small RNA sequencing from total RNA or Ago2 associated small RNAs extracted from HHV-6 infected Sup-T-1 cells
Project description:We report the application of size selection of small RNA species isolated from Jjhan cells harboring the human herpesvirus 6A genome. We ammassed >3.4million reads of sequence from three different sources: Normal Brain cell total RNA, Jjhan total RNA and HHV-6A BAC transfected Jjhan total RNA. Sequences were mapped to the HHV-6A Uganda 1102 strain genome (GenBank: X83413.1) with no less than 100% match for reads >20nt and <23nt. The resulting pool of candidates was mapped to the HHV-6A genome. Single pass 36nt sequencing of samples either with or without HHV-6a genomes present.
Project description:Primary human M1 and M2 macrophages were transfected with different human herpesvirus-derived viral miRNA and the impact on the cellular microRNAs was profiled using microarray. Viral miRNA-mediated impact was assessed on the host cellular microRNA profiles by miRNA microarray analysis. Five different viral miRNA representing 4 different human herpesviruses were overexpressed in M1 and M2 macrophages and the changes in cellular miRNA compared to control mimic were examined. Viral miRNA exhibit unique impact on M1 and M2 miRNA profiles.
Project description:MicroRNAs are 19 to 23 nt RNAs that post-transcriptionally regulate gene expression. Human cells express several hundred miRNAs which regulate important biological pathways such as development, proliferation, and apoptosis. Recently, 12 microRNA genes have been identified within the genome of Kaposi’s sarcoma-associated herpesvirus; however, their functions are still unknown. To identify host cellular genes that may be targeted by these novel viral regulators, we performed gene expression profiling in cells stably expressing KSHV-encoded miRNAs. Data analysis revealed a set of 81 genes whose expression was significantly changed in the presence of miRNAs. While the majority of changes were below 2-fold, eight genes were down-regulated between 4- and 20-fold. We confirmed miRNA-dependent regulation for three of these genes and found that protein levels of thrombospondin 1 (THBS1) were decreased >10-fold. THBS1 has previously been reported to be down-regulated in KS lesions and has known activity as a strong tumor suppressor and anti-angiogenic factor, exerting its anti-angiogenic effect in part by activating the latent form of TGF-b. We show that reduced THBS1 expression in the presence of viral miRNAs translates into decreased TGF-b activity. These data suggest that KSHV-encoded miRNAs may contribute directly to pathogenesis by down-regulation of THBS1, a major regulator of cell adhesion, migration, and angiogenesis. Keywords: comparison, experiemental versus control