Daniel D. Loeb, Ph.D.
Professor of Oncology
B.S., 1981, Biochemistry, Pennsylvania
State University
Ph.D., 1988, Microbiology and
Immunology, University of North Carolina at Chapel
Hill
Postdoctoral research: University of
North Carolina at Chapel Hill and University of
California, San Francisco
Office: 723A McArdle
Laboratory
Telephone: Office - (608) 262-1260; Lab -
(608) 262-2199
Email: loeb@oncology.wisc.edu
Research Interests: Molecular biology of the hepatitis B viruses
Research Description: Hepatitis B viruses (HBV) are a family of DNA viruses that can persistently infect the liver of a variety of animal hosts including humans. There is a close association between chronic HBV infection and hepatocellular carcinoma, though the mechanism of oncogenesis is not understood. Although they have a DNA genome, hepadnaviruses replicate via reverse transcription of an RNA intermediate (RNA pregenome) resulting in a relaxed circular DNA genome. The major project in our laboratory is understanding the mechanism of HBV reverse transcription. We are studying the mechanisms of RNA encapsidation, initiation and synthesis of minus-strand DNA, initiation and synthesis of plus-strand DNA, and genome circularization during plus-strand DNA synthesis. To understand the mechanism of these processes during reverse transcription we are (1) defining the cis-acting sequences involved in each step of the process, (2) determining the role of the viral trans-acting factors in each step of the process, and (3) determining the nature of the interactions between the trans-acting factors and the cis-acting elements during the process of reverse transcription.
Selected recent publications
Lentz, T. B., and Loeb, D. D. Roles of the Envelope Proteins in the Amplification of Covalently Closed Circular DNA and Completion of Synthesis of the Plus-Strand DNA in Hepatitis B Virus. J. Virol., 85: 11916-11927, 2011.
Lewellyn, E. B., and Loeb, D. D. The Arginine Clusters of the Carboxy-Terminal Domain of the Core Protein of Hepatitis B Virus Make Pleiotropic Contributions to Genome Replication. J. Virol., 85: 1298-1309, 2011.
Lewellyn, E. B., and Loeb, D. D. Serine Phosphoacceptor Sites within the Core Protein of Hepatitis B Virus Contribute to Genome Replication Pleiotropically. PLoS One, 6(2):e17202, 2011
Lentz, T. B., and Loeb, D. D. Development of Cell Cultures That Express Hepatitis B Virus to High Levels and Accumulate cccDNA. J. Virol. Methods, 169: 52-60, 2010.
Maguire, M. L., and Loeb, D. D. cis-Acting Sequences That Contribute to Synthesis of Minus-Strand DNA Are Not Conserved between Hepadnaviruses. J. Virol., 84: 12824-12831, 2010.
Porterfield, J. Z., Dhason, M. S., Loeb, D. D., Nassal, M., Stray, S. J., and Zlotnick, A. Full-Length Hepatitis B Virus Core Protein Packages Viral and Heterologous RNA with Similarly High Levels of Cooperativity. J. Virol., 84: 7174-7184, 2010.
Abraham, T. M., Lewellyn, E. B., Haines, K. M., and Loeb, D. D. Characterization of the Contribution of Spliced RNAs of Hepatitis B Virus to DNA Synthesis in Transfected Cultures of Huh7 and HepG2 Cells. Virology, 379: 30-37, 2008.
Abraham, T. M., and Loeb, D. D. The Topology of Hepatitis B Virus Pregenomic RNA Promotes Its Replication. J. Virol., 81: 11577-11584, 2007.
Haines, K. M., and Loeb, D. D. The Sequence of the RNA Primer and the DNA Template Influence the Initiation of Plus-strand DNA Synthesis in Hepatitis B Virus. J. Mol. Biol., 370: 471-480, 2007.
Lewellyn, E. B., and Loeb, D. D. Base Pairing Between cis-Acting Sequences Contributes to Template Switching during Plus-Strand DNA Synthesis in Human Hepatitis B Virus. J. Virol., 81: 6207-6215, 2007.