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The 11 th International Workshop on KSHV & Related Agents, Birmingham, UK
Virus-Cell Interactions I Abstract 27
KSHV AND CELLULAR MIRNA EXPRESSION DURING LATENCY AND LYTIC
REACTIVATION IN PEL CELLS
*1Soo-Jin Han * 1 Jianhong Hu, * 1 Karlie Plaisance * 2 Wendell Miley 2 Rachel Bagni, Chang
Hee Kim 3 , 2 Denise Whitby and 2 Rolf Renne
1. Department of Molecular Genetics and Microbiology, University of Florida, Gainesville,
Florida 32610, 2.Viral Oncology Section, AIDS and Cancer Virus Program, SAIC-
Frederick, NCI-Frederick, Frederick MD 21702 3. Laboratory of Molecular Technology,
Advanced Technology Program, SAIC-Frederick, NCI-Frederick, Frederick, MD 21702
(*equal contribution).
Abstract
MicroRNAs are small non-coding RNA molecules which post-transcriptionally regulate
gene expression by binding to 3’UTRs of target genes thereby contributing to important
biological processes. Kaposi’s sarcoma associated herpesvirus (KSHV) encodes 12
miRNAs within the KSHV latency associated region (KLAR), some of which target host
cellular genes thereby affecting angiogenesis, apoptosis, and B cell development.
Originally, KSHV miRNAs were cloned from BCBL-1 cells in the presence and absence of
TPA induction, suggesting that miRNAs may contribute to both phases of infection.
The KLAR region is expressed from at least three different promoters giving rise to singly
and multiply spliced transcripts. To further elucidate the complexity of this locus with
emphasis on transcripts that could serve as pri-miRNAs, we performed a detailed RT-PCR
and RNase protection analysis and identified several new transcripts that could give rise
to miRNA expression. We identified novel multiply-spliced transcripts originating from the
LANAp and LTI promoters upstream of LANA, which contained 3’ exons within the
Kaposin locus. Furthermore, the observed splicing patterns from these long KLAR
encompassing transcripts changed during lytic replication, suggesting that both LANAp
and LTI could drive miRNA expression.
Next, we utilized a custom miRNA array containing both viral and human miRNAs to
investigate miRNA output in PEL cells during latency and reactivated by Ad-ORF50.
Surprisingly, while we identified marked changes in the splicing pattern in this region,
viral miRNA expression was not significantly altered in PEL cells 48 hours post
reactivation. Cellular miRNA expression signatures during both conditions will also be
discussed.
Presenting author Email: rrenne@ufscc.ufl.edu
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