MiR-K12-6-5p expression changes of human transcripts
ABSTRACT: Transcriptional profiling of BJAB cells expressing miR-K12-6-5p. To identify host RNA targets of KSHV miRNAs, we took advantage of the observation that RNAs targeted by miRNAs often display small reductions in their steady-state levels, perhaps as a result of their impaired translation. Accordingly, we examined cellular transcript accumulation by array-based expression profiling under four sets of conditions in which KSHV miRNAs were expressed. Cells transfected with negative control miRNA compared to miR-K12-6-5p.
Project description:Transcriptional profiling of BJAB cells expressing miR-K12-9 and BCBL cells treated with miR-K12-9 inhibitor. To identify host RNA targets of KSHV miRNAs, we took advantage of the observation that RNAs targeted by miRNAs often display small reductions in their steady-state levels, perhaps as a result of their impaired translation. Accordingly, we examined cellular transcript accumulation by array-based expression profiling under four sets of conditions in which KSHV miRNAs were expressed or inhibited. Cells transfected with negative control miRNA compared to miR-K12-9 or negative miRNA inhibitor compared to miR-K12-9 inhibitor.
Project description:Transcriptional profiling of BJAB cells expressing miR-K10a and BCBL cells treated with miR-K10a inhibitor. To identify host RNA targets of KSHV miRNAs, we took advantage of the observation that RNAs targeted by miRNAs often display small reductions in their steady-state levels, perhaps as a result of their impaired translation. Accordingly, we examined cellular transcript accumulation by array-based expression profiling under three sets of conditions in which KSHV miRNAs were expressed or inhibited. Cells transfected with negative control miRNA compared to miR-K10a or negative miRNA inhibitor compared to miR-K10a inhibitor. The publication associated with this data set is about human TNFRSF12A/TWEAKR being targeted by KSHV miR-K10a.
Project description:Transcriptional profiling of BJAB cells expressing miR-K5 and BCBL cells treated with miR-K5 inhibitor. To identify host RNA targets of KSHV miRNAs, we took advantage of the observation that RNAs targeted by miRNAs often display small reductions in their steady-state levels, perhaps as a result of their impaired translation. Accordingly, we examined cellular transcript accumulation by array-based expression profiling under four sets of conditions in which KSHV miRNAs were expressed or inhibited. Keywords: Experimental treatment versus control treatment Cells transfected with negative control miRNA compared to miR-K5 or negative miRNA inhibitor compared to miR-K5 inhibitor or stable cells transduced with empty vector compared to stable cells transduced to express miR cluster K1,2,3,4,5.
Project description:All metazoan eukaryotes express microRNAs (miRNAs), ~22 nt long regulatory RNAs that can repress the expression of mRNAs bearing complementary sequences. Several DNA viruses also express miRNAs in infected cells, suggesting a role in viral replication and pathogenesis. While specific viral miRNAs have been shown to autoregulate viral mRNAs or downregulate cellular mRNAs via novel target sites, the function of the majority of viral miRNAs remains unknown. Here, we report that the miR-K12-11 miRNA encoded by Kaposi’s Sarcoma Associated Herpesvirus (KSHV) shows significant homology to cellular miR-155, including the entire miRNA “seed” region. Using a range of assays, we demonstrate that expression of physiological levels of miRK12- 11 or miR-155 results in the downregulation of an extensive set of common mRNA targets, including genes with known roles in cell growth regulation. Our findings indicate that viral miR-K12-11 functions as an ortholog of cellular miR-155 and has likely evolved to exploit a pre-existing gene regulatory pathway in B-cells. Moreover, the known etiological role of miR-155 in B-cell transformation suggests the possibility that miR-K12-11 may contribute to the induction of KSHV positive B-cell tumors in infected patients. BJAB cells were infected and sorted 48 hours after infection. 12 to 16 days after transduction, gene expression analysis of 10 independent BJAB cell pools, expressing AcGFP only or AcGPF and miR-K12-11, was performed using Human Operon v3.0.2 arrays. Each ample was run against Universal Human Reference RNA, Stratagene. # of Arrays: BJAB = 3 AcGFP only = 10 AcGFP miR-K12-11 = 11
Project description:Seventeen miRNAs encoded by Kaposi's sarcoma-associated herpesvirus (KSHV) have been identified and their functions have begun to be characterized. Among these miRNAs, we report here that miR-K12-7 directly targets the replication and transcription activator (RTA) encoded by open reading frame 50. We found that miR-K12-7 targeted the RTA 3' untranslated region (RTA3'UTR) in a seed sequence-dependent manner. miR-K12-7-5p derived from miR-K12-7 mediates the inhibition of RTA expression, and the mutation of the seed match site totally abrogated the inhibitory effect of miR-K12-7 on RTA3'UTR. The inhibition of RTA expression by miR-K12-7 was further confirmed in the latently KSHV-infected 293/Bac36 cell line through transient transfection of miR-K12-7 expression plasmid or specific inhibitor of miR-K12-7-5p, respectively. The transient transfection of miR-K12-7 into 293/Bac36 cells reduced RTA expression and the expression of the downstream early genes regulated by RTA, and also the production of progeny virus was significantly reduced after treatment with chemical inducers. Our study revealed that another miRNA, miR-K12-7-5p, targets the viral immediate early gene RTA and that this miRNA contributes to the maintenance of viral latency.
Project description:BJAB cells were infected with pNL-SIN-CMV-AcGFP (see accession number GSE8867 for data) or pNL-SIN-CMV-AcGFP expressing KSHV miR-K1, miR-K12-11 or miR-K4-3p and sorted 48 hours after infection. 12 or 16 days after transduction, cytoplasmic RNA was harvested and gene expression analysis of independent BJAB cell pools was performed using Human Operon v3.0.2 arrays. Each sample was run against Universal Human Reference RNA, Stratagene. The samples listed here were processed in parallel to those with accession number GSE8867, which includes all matched control cell lines. 6 independent B cell pools each expressing KSHV miR-K1, miRK12-11, or miR-K4-3p are included. Matched controls include unmodified BJAB (3 arrays) and cells transducted with parental vector pNL-SIN-CMV-AcGFP (6 replicates).
Project description:Kaposi's sarcoma (KS) as the most common AIDS-associated malignancy is etiologically caused by KS-associated herpesvirus (KSHV). KS is a highly disseminated and vascularized tumor. KSHV encodes 12 pre-microRNAs that yield 25 mature microRNAs (miRNAs), but their roles in KSHV-induced tumor metastasis and angiogenesis remain largely unclear. KSHV-encoded miR-K12-6 (miR-K6) can generate two mature miRNAs, miR-K6-5p and miR-K6-3p. Recently, we have shown that miR-K6-3p induced cell migration and angiogenesis via directly targeting SH3 domain binding glutamate-rich protein (SH3BGR). Here, by using mass spectrometry, bioinformatics analysis and luciferase reporter assay, we showed that miR-K6-5p directly targeted the coding sequence of CD82 molecule (CD82), a metastasis suppressor. Ectopic expression of miR-K6-5p specifically inhibited the expression of endogenous CD82 and strongly promoted endothelial cells invasion and angiogenesis. Overexpression of CD82 significantly inhibited cell invasion and angiogenesis induced by miR-K6-5p. Mechanistically, CD82 directly interacted with c-Met to inhibit its activation. MiR-K6-5p directly repressed CD82, relieving its inhibition on c-Met activation and inducing cell invasion and angiogenesis. Lack of miR-K6 abrogated KSHV suppression of CD82 resulting in compromised KSHV activation of c-Met pathway, and KSHV induction of cell invasion and angiogenesis. In conclusion, our data show that by reducing CD82, KSHV miR-K6-5p expedites cell invasion and angiogenesis by activating the c-Met pathway. Our findings illustrate that KSHV miRNAs may be critical for the dissemination and angiogenesis of KSHV-induced malignant tumors.
Project description:Kaposi's sarcoma associated herpes virus (KSHV) is associated with tumors of endothelial and lymphoid origin. During latent infection, KSHV expresses miR-K12-11, an ortholog of the human tumor gene hsa-miR-155. Both gene products are microRNAs (miRNAs), which are important post-transcriptional regulators that contribute to tissue specific gene expression. Advances in target identification technologies and molecular interaction databases have allowed a systems biology approach to unravel the gene regulatory networks (GRNs) triggered by miR-K12-11 in endothelial and lymphoid cells. Understanding the tissue specific function of miR-K12-11 will help to elucidate underlying mechanisms of KSHV pathogenesis.Ectopic expression of miR-K12-11 differentially affected gene expression in BJAB cells of lymphoid origin and TIVE cells of endothelial origin. Direct miRNA targeting accounted for a small fraction of the observed transcriptome changes: only 29 genes were identified as putative direct targets of miR-K12-11 in both cell types. However, a number of commonly affected biological pathways, such as carbohydrate metabolism and interferon response related signaling, were revealed by gene ontology analysis. Integration of transcriptome profiling, bioinformatic algorithms, and databases of protein-protein interactome from the ENCODE project identified different nodes of GRNs utilized by miR-K12-11 in a tissue-specific fashion. These effector genes, including cancer associated transcription factors and signaling proteins, amplified the regulatory potential of a single miRNA, from a small set of putative direct targets to a larger set of genes.This is the first comparative analysis of miRNA-K12-11's effects in endothelial and B cells, from tissues infected with KSHV in vivo. MiR-K12-11 was able to broadly modulate gene expression in both cell types. Using a systems biology approach, we inferred that miR-K12-11 establishes its GRN by both repressing master TFs and influencing signaling pathways, to counter the host anti-viral response and to promote proliferation and survival of infected cells. The targeted GRNs are more reproducible and informative than target gene identification, and our approach can be applied to other regulatory factors of interest.
Project description:Kaposi's sarcoma-associated herpesvirus (KSHV) is a human tumor virus that encodes 12 precursor microRNAs (pre-miRNAs) that give rise to 17 different known approximately 22-nucleotide (nt) effector miRNAs. Like all herpesviruses, KSHV has two modes of infection: (1) a latent mode whereby only a subset of viral genes are expressed and (2) a lytic mode during which the full remaining viral genes are expressed. To date, KSHV miRNAs have been mostly identified via analysis of cells that are undergoing latent infection. Here, we developed a method to profile small RNAs ( approximately 18-75 nt) from populations of cells undergoing predominantly lytic infection. Using two different next-generation sequencing platforms, we cloned and sequenced both pre-miRNAs and derivative miRNAs. Our analysis shows that the vast majority of viral and host 5p miRNAs are co-terminal with the 5' end of the cloned pre-miRNAs, consistent with both being defined by microprocessor cleavage. We report the complete repertoire (25 total) of 5p and 3p derivative miRNAs from all 12 previously described KSHV pre-miRNAs. Two KSHV pre-miRNAs, pre-miR-K12-8 and pre-miR-K12-12, encode abundant derivative miRNAs from the previously unreported strands of the pre-miRNA. We identify several novel small RNAs of low abundance, including viral miRNA-offset-RNAs (moRNAs), and antisense viral miRNAs (miRNA-AS) that are encoded antisense to previously reported KSHV pre-miRNAs. Finally, we observe widespread antisense transcription relative to known coding sequences during lytic replication. Despite the enormous potential to form double-stranded RNA in KSHV-infected cells, we observe no evidence for the existence of abundant viral-derived small interfering RNAs (siRNAs).
Project description:Background:We previously reported Kaposi sarcoma-associated herpesvirus (KSHV) microRNA sequence variants in clinical samples correlated with increased risk of multicentric Castleman's disease (MCD). We then demonstrated that microRNAs with variant sequence have different maturation and mature microRNA expression in vitro. Here, we illustrate the association between microRNA sequence and changes in mature microRNA levels within Kaposi sarcoma (KS) lesions. Methods:KSHV microRNA sequences were determined from 20 KS lesions and 4 control skin biopsies from individuals evaluated for KS. Levels of mature KSHV microRNAs were measured with 21 custom small RNA qRT-PCR assays using RNA RNU6B as endogenous control. Results:The levels of 13 KSHV-encoded microRNAs were elevated in KS lesions compared to control biopsies. MicroRNA 9-5p was strongly down regulated in South African vs. US biopsies. Low levels of K12-9-5p were associated with single nucleotide polymorphisms (SNPs) in miR-K12-9-5p, 4-5p, 5-3p, 7-3p and pri-miR-K12-3. One SNP in pri-miR-K12-3 resulted in down regulation of miR-K12-6-3p, 8-3p, 10-3p, 12-5p and the upregulation of 5-5p, illustrating sequence variants outside pre-microRNAs were also associated with changes in mature microRNA levels. Conclusions:The levels of mature KSHV-encoded microRNAs in KS lesions correlate with sequence variation reflecting changes in secondary and tertiary RNA structure.