Christopher S Sullivan

Associate Professor
Molecular Biosciences

Our lab aims to understand how DNA tumor viruses interact with host RNAi machineries to replicate, induce tumors, and cause pathogenesis.

Phone: 512-471-5391

Office Location
NMS 3.218

Postal Address
The University of Texas at Austin
Molecular Biosciences, College of Natural Sciences
2506 Speedway
Austin, TX 78712

Research Summary:

The discovery of RNA interference (RNAi) and small regulatory RNAs such as siRNAs and miRNAs, has dramatically changed our understanding of the regulation of gene expression. Consequently, RNAi has generated much excitement due to its regulatory and therapeutic potential. Our research focuses on understanding the interaction of viruses with the RNAi machinery in mammalian cells.

We have shown that members of different tumor virus families (including Polyomaviridae, Herpesviridae, and Retroviridae) encode microRNAs; likely to aid in their own replication and to promote infectivity. Members of the Polyoma virus family induce tumors in model organisms and at least one member (MCV) is associated with human tumors. Kaposi's Sarcoma associated Herpes Virus (KSHV) promotes highly vascularized skin lesions and rare B cell lymphomas, predominantly in immunosuppresed AIDS patients.

Our goals are several-fold: (1) to understand the functions of viral and host encoded microRNAs and how they contribute to viral lifecycle, pathogenesis and tumorigenesis, (2) to identify novel interactions of mammalian viruses with the host RNAi machinery, (3) to uncover new mechanisms of gene regulation utilized by tumor viruses and the host in response to infection, and (4) to use viruses as "molecular divining rods" to probe for new classes of host defense pathways.

2012 Kincaid RP, Burke JM, Sullivan CS, RNA virus microRNA that mimics a B-cell oncomiR, PNAS In press

2011 YT Lin and Sullivan CS, Expanding the Role of Drosha to the Regulation of Viral Gene Expression, PNAS 108(27): 11229-34

2011 Chen CJ, Kincaid RP, Seo GJ, Bennett MD, Sullivan CS, Insights into Polyomaviridae microRNA function derived from the study of the bandicoot papillomatosis carcinomatosis viruses., J Virol 85(9): 4487-500

2010 Lin YT, Kincaid RP, Arasappan D, Dowd SE, Hunicke-Smith SP, Sullivan CS., Small RNA profiling reveals antisense transcription throughout the KSHV genome and novel small RNAs, RNA 16(8): 1540-58

2009 Ziegelbauer JM, Sullivan CS, Ganem D., Tandem array-based expression screens identify host mRNA targets of virus-encoded microRNAs, Nat Genet 141: 130-4

2009 Seo GJ, Chen CJ, Sullivan CS., Merkel cell polyomavirus encodes a microRNA with the ability to autoregulate viral gene expression, Virology 383: 183-7

2008 McClure LV, Sullivan CS., Kaposi's sarcoma herpes virus taps into a host microRNA regulatory network, Cell Host Microbe 3: 1-3

2008 Sullivan CS, New roles for large and small viral RNAs in evading host defences, Nat Rev Genet 9: 503-7

2008 Seo GJ, Fink LH, O'Hara B, Atwood WJ, Sullivan CS., Evolutionarily conserved function of a viral microRNA, J Virol 82: 9823-8

2005 CS Sullivan and Ganem D, A virus-encoded inhibitor that blocks RNA interference in mammalian cells, J. Virol 79: 7371-9

2005 CS Sullivan, Grundhoff AT, Tevethia S, Pipas JM, Ganem D, SV40-encoded microRNAs regulate viral gene expression and reduce susceptibility to cytotoxic T cells, Nature 435: 682-6