The experiments outlined in this proposal focus on RNA-RNA interactions in Flock House virus (FHV), a nonenveloped, icosahedral insect virus. The genome of FHV is split between two distinct, single-stranded, messenger-sense RNA molecules which are thought to be encapsidated into a single virion. The mechanism by which one copy of each genomic RNA is selected for packaging into a single particle is unknown. Preliminary studies from our laboratory have demonstrated that mild heating of purified virions induces formation of a stable heterodimeric RNA complex within the particle suggesting that the encapsidated nucleic acids undergo significant structural rearrangements. Furthermore, mild dissociation of FHV provirions has revealed that this complex may already exist prior to heating, albeit in a more labile form. Heterodimer formation is hypothesized to provide a means by which the two RNAs are copackaged during assembly of virus particles. In this application, we intend to isolate the labile heterodimer from purified virions and/or reconstitute it in vitro and plan to characterize it using various biochemical, physical and molecular genetic methods. In addition, in collaboration with Dr. John E. Johnson's laboratory, a newly developed low resolution X-ray crystallography technique will be utilized to visualize changes in RNA structure induced upon heating of FHV particles. The results from the proposed studies should provide new insights into the mechanisms of RNA packaging in segmented viruses and the organization of the nucleic acid inside the virion. This knowledge could provide a basis for developing strategies of how to interfere with the life cycle of medically important viruses.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32AI010262-01A1
Application #
6012902
Study Section
Special Emphasis Panel (ZRG1-EVR (01))
Program Officer
Meegan, James M
Project Start
1999-06-01
Project End
Budget Start
1999-06-01
Budget End
2000-05-31
Support Year
1
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
City
La Jolla
State
CA
Country
United States
Zip Code
92037