Expression and Function of MicroRNAs Encoded by Kaposi's Sarcoma-associated Herpesvirus

Gottwein, Eva; Cai, Xinjiang; Cullen, Bryan R.

doi:10.1101/sqb.2006.71.004

Cited by 26 publications

(19 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…TPA treatment had little or no effect on the level of expression of miR-K1 through miR-K8 plus miR-K11, which are expressed under the control of a latent KSHV promoter, but did modestly induce expression of miR-K10 and miR-K12, which both lie 3Ј to a promoter induced during productive replication (Fig. 2B) (5,10). Similar data were also obtained for BC-1 cells (Fig.…”

Section: Resultssupporting

confidence: 73%

In-Depth Analysis of Kaposi's Sarcoma-Associated Herpesvirus MicroRNA Expression Provides Insights into the Mammalian MicroRNA-Processing Machinery

Umbach

Cullen

2010

J Virol

124

147

View full text Add to dashboard Cite

We have used deep sequencing to analyze the pattern of viral microRNA (miRNA) expression observed in the B-cell line BC-3, which is latently infected with Kaposi's sarcoma-associated herpesvirus (KSHV). We recovered 14.6 ؋ 10 6 total miRNA cDNA reads, of which a remarkable 92% were of KSHV origin. We detected 11 KSHV miRNAs as well as all 11 predicted miRNA* or passenger strands from the miRNA duplex intermediate. One previously reported KSHV miRNA, miR-K9, was found to be mutationally inactivated. This analysis revealed that the 5 ends of 10 of the 11 KSHV miRNAs were essentially invariant, with significantly more variation being observed at the 3 end, a result which is consistent with the proposal that the 5-proximal region of miRNAs is critical for target mRNA recognition. However, one KSHV miRNA, miR-K10-3p, was detected in two isoforms differing by 1 nucleotide (nt) at the 5 end that were present at comparable levels, and these two related KSHV miRNAs are therefore likely to target at least partially distinct mRNA populations. Finally, we also report the first detection of miRNA offset RNAs (moRs) in vertebrate somatic cells. moRs, which derive from primary miRNA (pri-miRNA) sequences that immediately flank the mature miRNA and miRNA* strands, were identified flanking one or both sides of nine of the KSHV miRNAs. These data provide new insights into the pattern of miRNA processing in mammalian cells and indicate that this process is highly conserved during animal evolution.MicroRNAs (miRNAs) are a recently discovered class of ϳ22-nucleotide (nt) noncoding RNAs that play a key role in the posttranscriptional regulation of gene expression in all multicellular eukaryotes (reviewed in reference 3). Most miRNAs are initially transcribed by RNA polymerase II as part of a long capped and polyadenylated precursor transcript called a primary miRNA (pri-miRNA) (6,20). At this stage, the mature miRNA forms part of one arm of an imperfect ϳ80-nt RNA stem-loop structure that is recognized by the nuclear microprocessor complex, consisting of the RNase III enzyme Drosha and its cofactor DGCR8 (8,11,15). Drosha cleaves the pri-miRNA to liberate an ϳ60-nt-long pre-miRNA hairpin bearing a 2-nt 3Ј overhang (19,38). After export to the cytoplasm, the pre-miRNA is bound by a second RNase III enzyme, called Dicer, which cleaves the pre-miRNA ϳ22 bp from the base, leaving a second 2-nt 3Ј overhang, to generate the miRNA duplex intermediate (16). One strand of this duplex intermediate-the mature miRNA strand-is then incorporated into the RNA-induced silencing complex (RISC) (14), while the second strand-referred to as the passenger or miRNA* strand-is degraded. Selection of which strand of the miRNA duplex intermediate is incorporated into RISC is largely determined by the stability of base pairing at the 5Ј end of each strand, with the less tightly base-paired strand being preferentially selected (17,29). However, this discrimination is not absolute, and miRNA* strands are also occasionally incorporated into RISC and have been re...

show abstract

Section: Resultssupporting

confidence: 73%

In-Depth Analysis of Kaposi's Sarcoma-Associated Herpesvirus MicroRNA Expression Provides Insights into the Mammalian MicroRNA-Processing Machinery

Umbach

Cullen

2010

J Virol

124

147

View full text Add to dashboard Cite

show abstract

“…For example, a mutation in the seed region of mir-96 was shown to lead to hearing loss in a mouse model [184] and was identified in families with non-syndromic progressive sensorineural hearing loss [185], while a point mutation in the viral mir-K5 precursor stem loop was shown to interfere with its processing and reduce mature miR-K5 accumulation [186]. Germline deletion of the mir-17-92 gene cluster was another recent example causing skeletal growth defects in humans [187].…”

Section: 6 Alterations Of Mirna Sequencementioning

confidence: 99%

MicroRNAs in Human Cancer

Farazi

Hoell

Morozov

et al. 2012

Advances in Experimental Medicine and Biology

616

503

View full text Add to dashboard Cite

Mature microRNAs (miRNAs) are single-stranded RNA molecules of 20–23-nucleotide (nt) length that control gene expression in many cellular processes. These molecules typically reduce the translation and stability of mRNAs, including those of genes that mediate processes in tumorigenesis, such as inflammation, cell cycle regulation, stress response, differentiation, apoptosis, and invasion. miRNA targeting is initiated through specific base-pairing interactions between the 5′ end (“seed” region) of the miRNA and sites within coding and untranslated regions (UTRs) of mRNAs; target sites in the 3′ UTR lead to more effective mRNA destabilization. Since miRNAs frequently target hundreds of mRNAs, miRNA regulatory pathways are complex. To provide a critical overview of miRNA dysregulation in cancer, we first discuss the methods currently available for studying the role of miRNAs in cancer and then review miRNA genomic organization, biogenesis, and mechanism of target recognition, examining how these processes are altered in tumorigenesis. Given the critical role miRNAs play in tumorigenesis processes and their disease specific expression, they hold potential as therapeutic targets and novel biomarkers.

show abstract

“…The relative differences in miRNA abundance in this study in comparison to previous work could be due to the different sources of RNA, that is, latently infected tumor cells versus lytically infected cells. It has been shown from studies of other gammaherpesviruses, that the state of viral infection, whether lytic or latent, can impact the overall levels of viral miRNAs in infected cells (Cai et al 2005Gottwein et al 2006). As expected, there was no detection of mature miRNAs from the cells infected with gHV68D9473, a mutant virus lacking the left end 9.5 kb of the gHV68 genome, including the viral miRNA coding region (Clambey et al 2002).…”

Section: Identification Of Mature Mirnas Using Rlm-rt-pcrmentioning

confidence: 99%

“…In EBV infections, global expression levels of mature EBV miRNAs can vary 25-to 50-fold based on the cell type infected (Pratt et al 2009). In both EBV and KSHV infections, it has been demonstrated that the infection state of the virus, whether lytic, latent, or in specific stages of latency, can have a profound effect on viral miRNA production Gottwein et al 2006). Additionally, RNA pol III transcription has also been reported to vary based on the cellular context of infection as shown with EBER gene expression (FeltonEdkins et al 2006).…”

mentioning

confidence: 99%

Mature and functional viral miRNAs transcribed from novel RNA polymerase III promoters

Diebel¹,

Smith²,

Dyk³

2009

RNA

113

View full text Add to dashboard Cite

Murid herpesvirus 4 (MuHV-4) microRNAs were previously cloned from latently infected tumor cells and predicted to be processed from a series of RNA polymerase III primary transcripts. We detected maturely processed MuHV-4 miRNAs within total RNA from lytically infected cells in vitro and infected tissues ex vivo, using a highly sensitive reverse ligation meditated RT-PCR strategy. We determined that the MuHV-4 microRNAs are biologically active during infection by a luciferase reporter system. We experimentally demonstrated that transcription of the MuHV-4 microRNAs is by RNA polymerase III by a-amanitin insensitivity and by specific deletion of the RNA polymerase III type 2-like promoter elements of MuHV-4, resulting in the complete loss of miRNA detection and function. Finally, we demonstrate that these 10 viral miRNAs, each transcribed from highly conserved and novel polymerase III promoter elements, vary markedly in their relative abundance and activity.

show abstract

Expression and Function of MicroRNAs Encoded by Kaposi's Sarcoma-associated Herpesvirus

Cited by 26 publications

References 36 publications

In-Depth Analysis of Kaposi's Sarcoma-Associated Herpesvirus MicroRNA Expression Provides Insights into the Mammalian MicroRNA-Processing Machinery

In-Depth Analysis of Kaposi's Sarcoma-Associated Herpesvirus MicroRNA Expression Provides Insights into the Mammalian MicroRNA-Processing Machinery

MicroRNAs in Human Cancer

Mature and functional viral miRNAs transcribed from novel RNA polymerase III promoters

Contact Info

Product

Resources

About