Numerous conserved and divergent microRNAs expressed by herpes simplex viruses 1 and 2
Igor Jurak1, Martha F Kramer, Joseph C Mellor
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Ave., Boston, MA 02115, USA.
Journal of Virology
|February 26, 2010
Summary
Herpes simplex virus (HSV) microRNAs (miRNAs) were comprehensively analyzed using sequencing. Researchers identified novel viral miRNAs and conserved elements, aiding functional studies.
Area of Science:
- Virology
- Molecular Biology
- Genomics
Background:
- Viruses utilize microRNAs (miRNAs) for gene regulation.
- Previous studies identified limited herpes simplex virus (HSV) miRNAs.
- A need exists for comprehensive analysis of HSV-encoded miRNAs.
Purpose of the Study:
- To comprehensively identify and analyze microRNAs (miRNAs) encoded by herpes simplex virus 1 (HSV-1) and HSV-2.
- To investigate the conservation and divergence of viral miRNAs between HSV-1 and HSV-2.
- To characterize novel viral miRNAs and related RNA species.
Main Methods:
- Massively parallel sequencing was employed to profile miRNAs.
- Bioinformatic analysis was used to identify viral miRNAs and their genomic locations.
- Sequence and positional conservation of miRNAs between HSV-1 and HSV-2 were assessed.
Main Results:
- 16 and 17 miRNAs were identified in HSV-1 and HSV-2, respectively, including novel species.
- Most viral miRNAs are located within or near the latency-associated transcript region.
- Nine miRNAs showed conservation between HSV-1 and HSV-2, with notable conservation in seed regions.
Conclusions:
- This study provides a comprehensive catalog of HSV-1 and HSV-2 encoded miRNAs.
- Identified conserved and divergent viral miRNAs offer insights into their functions.
- Discovery of miRNA-offset RNAs (moRs) expands understanding of viral RNA processing.
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