The mechanism of DNA packaging for double-stranded DNA viruses will be studied in the Bacillus subtilis bacteriophage X29, the most efficient in vitro viral packaging system known. Using an integrated genetic, biochemical and structural approach, we will characterize protein conformational change and movement in the transiently assembled packaging motor during DNA encapsidation. The mechanism of packaging in X29 will serve as a model for animal virus packaging in the analogous herpesvirus and adenovirus systems, and aid in the search for new antiviral therapies. Due to similarities between the X29 ATPase and other ring translocases, insights gained from the study of X29 packaging will also provide insight into the basic principles of macromolecular motor function in higher organisms. To elucidate the mechanism of DNA packaging: an atomic structure of the X29 DNA packaging motor will be obtained by fitting of X-ray crystallographic structures of motor components into high-resolution cryoEM maps of the motor complex (Aim 1);high-resolution cryoEM reconstruction of packaging intermediates will identify mobile elements during DNA packaging (Aim 2);mutagenesis and biochemical analysis will dissect functional residues in the ATPase and connector that are crucial for DNA packaging (Aim 3);and, packaging motors containing chimeric pRNAs will be created to probe the global assembly, operation and communication of the X29 DNA packaging motor (Aim 4).

Public Health Relevance

The assembly and movement of macromolecules in biological systems drive all aspects of health and disease at the cellular level. Study of the structure, assembly and function of the bacterial virus X29 DNA packaging motor serves as a model for understanding these fundamental biological principles and can inform us about similar processes in higher organisms. The DNA packaging process of X29 will also serve as a model for understanding similar events in the medically relevant herpesviruses and adenoviruses, thus providing targets for the development of new antiviral therapies.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM095516-02
Application #
8337276
Study Section
Prokaryotic Cell and Molecular Biology Study Section (PCMB)
Program Officer
Sakalian, Michael
Project Start
2011-09-30
Project End
2015-08-31
Budget Start
2012-09-01
Budget End
2013-08-31
Support Year
2
Fiscal Year
2012
Total Cost
$313,409
Indirect Cost
$56,893
Name
University of Minnesota Twin Cities
Department
Dentistry
Type
Schools of Dentistry
DUNS #
555917996
City
Minneapolis
State
MN
Country
United States
Zip Code
55455