AIDS and Cancer Virus Program

Biography

Robert J. Gorelick received his Ph.D. in 1985 from the University of Delaware, Department of Chemistry and Biochemistry studying enzymology of flavoproteins involved in fatty acid metabolism and electron transport. In 1985, he began his postdoctoral research with the ABL-Basic Research Program, Frederick National Laboratory for Cancer Research, and received an NIH National Research Service Award from 1988 to 1990 focusing efforts on determining the function of retroviral nucleocapsid proteins in virus assembly and infection processes. In 1990, Dr. Gorelick joined the AIDS and Cancer Virus Program serving as the Head of the Retroviral Mutagenesis Section since 1995.

Research Description

The majority of the research from this section focuses on retroviral nucleocapsid (NC) proteins and their highly conserved CCHC (-Cys-X₂-Cys-X₄-His-X₄-Cys-) Zn²⁺-fingers, located in Gag. Site-directed mutagenesis, protein chemistry, and cell culture techniques are used to study the functions of NC proteins in viral replication. Remarkable defects in viral assembly and replication processes result from various conservative alterations to NC and its highly conserved Zn²⁺-finger structures. Deficiencies included a reduction in the level of packaged genomes and severe defects in replication. Some mutants can package significant levels of genomic RNA, yet remain as much as 10⁶-fold less infectious than wild-type virus; compelling evidence demonstrating NC's involvement in assembly processes as well as other functions in viral infection. Extended studies have determined precisely what steps are disrupted in the replication process upon altering NC. Cell culture-based results show the involvement of NC in i) reverse transcription processes, ii) integration processes, and iii) the correct timing of reverse transcription initiation. The knowledge gained from these studies shows that NC and its Zn²⁺-fingers are extremely sensitive to mutagenic or chemical alteration, thus they are attractive antiviral targets.

This Section is also involved in the preparation, purification and distribution of mutant and wild-type recombinant NC proteins and full-length viral genomes to qualified research laboratories upon request by contacting Dr. Robert Gorelick (gorelicr@mail.nih.gov). NC proteins are produced and purified with the expert assistance of the ACVP Retroviral Protein Chemistry Core and genomes are prepared from virus generated by the ACVP Biological Products Core. The purpose of this endeavor is to assist other laboratories in assessing the molecular determinants of NC function. Such studies have greatly extended the understanding of the properties and functions of NC in viral replication.

Key Collaborators

• Judith G. Levin, NICHD, NIH
• Gilles Mirambeau, University of Barcelona, Spain
• Karin Musier-Forsyth, The Ohio State University
• Alan Rein, NCI
• Kevin M. Weeks, University of North Carolina-Chapel Hill
• Mark C. Williams, Northeastern University

Recent Publications

1. Gherghe, C., T. Lombo, C. W. Leonard, S. A. K. Datta, J. W. Bess, R. J. Gorelick, A. Rein, and K. M. Weeks. 2010. Definition of a high-affinity Gag recognition structure mediating packaging of a retroviral RNA genome. Proc. Natl. Acad. Sci. U.S.A. 107:19248-53.
2. Mirambeau, G., S. Lyonnais, D. Coulaud, L. Hameau, S. Lafosse, J. Jeusset, I. Borde, M. Reboud-Ravaux, T. Restle, R. J. Gorelick, and E. Le Cam. 2007. HIV-1 protease and reverse transcriptase control the architecture of their nucleocapsid partner. PLoS One. 2:e669.
3. Mirambeau, G., S. Lyonnais, and R. J. Gorelick. 2010. Features, processing states, and heterologous protein interactions in the modulation of the retroviral nucleocapsid protein function. RNA Biol. 7:85-95.
4. Qualley, D. F., K. M. Stewart-Maynard, F. Wang, M. Mitra, R. J. Gorelick, I. Rouzina, M. C. Williams, and K. Musier-Forsyth. 2010. C-terminal domain modulates the nucleic acid chaperone activity of human t-cell leukemia virus type 1 nucleocapsid protein via an electrostatic mechanism. J. Biol. Chem. 285:295-307.
5. Thomas, J. A., W. J. Bosche, T. L. Shatzer, D. G. Johnson, and R. J. Gorelick. 2008. Mutations in human immunodeficiency virus type 1 nucleocapsid protein zinc fingers cause premature reverse transcription. J. Virol. 82:9318-9328.
6. Thomas, J. A., T. D. Gagliardi, W. G. Alvord, M. Lubomirski, W. J. Bosche, and R. J. Gorelick. 2006. Human immunodeficiency virus type 1 nucleocapsid zinc-finger mutations cause defects in reverse transcription and integration. Virology 353:41-51.
7. Thomas, J. A., and R. J. Gorelick. 2008. Nucleocapsid protein function in early infection processes. Virus Res. 134:39-63.
8. Thomas, J. A., D. E. Ott, and R. J. Gorelick. 2007. Efficiency of human immunodeficiency virus type 1 postentry infection processes: Evidence against disproportionate numbers of defective virions. J. Virol. 81:4367-4370.
9. Watts, J. M., K. K. Dang, R. J. Gorelick, C. W. Leonard, J. W. Bess Jr, R. Swanstrom, C. L. Burch, and K. M. Weeks. 2009. Architecture and secondary structure of an entire HIV-1 RNA genome. Nature 460:711-716.
10. Wilkinson, K. A., R. J. Gorelick, S. M. Vasa, N. Guex, A. Rein, D. H. Mathews, M. C. Giddings, and K. M. Weeks. 2008. High-throughput SHAPE analysis reveals structures in HIV-1 genomic RNA strongly conserved across distinct biological states. PLoS Biol. 6:e96.

Staffing

• James A. Thomas, Ph.D., Scientist I
• Donald G. Johnson, Research Associate II
• William J. Bosche, Research Associate II