While adenoviral vectors continue to be employed in phase 1-III clinical trials for the treatment of cancers and cardiovascular diseases, we still have an incomplete understanding of the virus entry pathway. During the previous funding period, researchers in the Nemerow and Reddy laboratories at the Scripps Research Institute solved the crystal structure of adenovirus at near atomic resolution thereby revealing the locations, folds and interactions of several viral capsid proteins. Additional investigations in the Nemerow and Stewart laboratories (Vanderbilt) discovered that specific host factors either destabilize (alpha v integrins) the virus capsid or restrict (defensins) capsid disassembly. Although this information has shed further light on the mechanisms involved in virus entry into cells, numerous gaps remain in our knowledge of virus disassembly and membrane penetration events. In this proposal, a team of experienced investigators with expertise in molecular virology, structural biology, and biophysical techniques will investigate the precise mechanisms involved in capsid disassembly and membrane penetration by protein VI. X-ray diffraction and cryoEM structural analyses of several key capsid proteins including proteins VI, V and hexon will be undertaken. Advanced imaging of adenovirus by atomic force microscopy will be employed to measure the tensile strength and mechanical properties of the viral capsid. Native and denatured mass spectrometry will be used to determine the copy number of protein VI in the virion as well as its association states with other capsid proteins. Protein VI mutagenesis studies will analyze the role of protein VI in capsid assembly/disassembly and endosome penetration. The long-term goal of these studies is to obtain a more complete picture of host cell invasion by adenovirus. Such knowledge should bolster the emerging knowledge of how non-enveloped viruses breach host cell membranes as well as provide a foundation for the development of safer and more efficient viral vectors.

Public Health Relevance

The use of viral vectors, including adenovirus, is stymied by a fundamental lack of knowledge of their structure and cell entry mechanisms. Inevitably, this situation negatively impacts implementation of effective vaccine, antiviral and gene delivery strategies. The specific goals of this proposal seek to remedy this deficiency by undertaking a comprehensive analysis of two key events in the adenovirus life cycle, capsid disassembly and membrane penetration.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
2R01HL054352-18
Application #
8367976
Study Section
Virology - A Study Section (VIRA)
Program Officer
Banks-Schlegel, Susan P
Project Start
1995-01-20
Project End
2017-06-30
Budget Start
2012-08-01
Budget End
2013-06-30
Support Year
18
Fiscal Year
2012
Total Cost
$465,895
Indirect Cost
$215,895
Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Snijder, Joost; Benevento, Marco; Moyer, Crystal L et al. (2014) The cleaved N-terminus of pVI binds peripentonal hexons in mature adenovirus. J Mol Biol 426:1971-9
Benevento, Marco; Di Palma, Serena; Snijder, Joost et al. (2014) Adenovirus composition, proteolysis, and disassembly studied by in-depth qualitative and quantitative proteomics. J Biol Chem 289:11421-30
PĂ©rez-Vargas, Jimena; Vaughan, Robert C; Houser, Carolyn et al. (2014) Isolation and characterization of the DNA and protein binding activities of adenovirus core protein V. J Virol 88:9287-96
Sanchez-Cespedes, Javier; Moyer, Crystal L; Whitby, Landon R et al. (2014) Inhibition of adenovirus replication by a trisubstituted piperazin-2-one derivative. Antiviral Res 108:65-73
Reddy, Vijay S; Nemerow, Glen R (2014) Structures and organization of adenovirus cement proteins provide insights into the role of capsid maturation in virus entry and infection. Proc Natl Acad Sci U S A 111:11715-20
Snijder, Joost; Reddy, Vijay S; May, Eric R et al. (2013) Integrin and defensin modulate the mechanical properties of adenovirus. J Virol 87:2756-66
Flatt, Justin W; Kim, Robert; Smith, Jason G et al. (2013) An intrinsically disordered region of the adenovirus capsid is implicated in neutralization by human alpha defensin 5. PLoS One 8:e61571
Moyer, Crystal L; Nemerow, Glen R (2012) Disulfide-bond formation by a single cysteine mutation in adenovirus protein VI impairs capsid release and membrane lysis. Virology 428:41-7
Nemerow, Glen R; Stewart, Phoebe L; Reddy, Vijay S (2012) Structure of human adenovirus. Curr Opin Virol 2:115-21
Barlan, A U; Griffin, T M; McGuire, K A et al. (2011) Adenovirus membrane penetration activates the NLRP3 inflammasome. J Virol 85:146-55

Showing the most recent 10 out of 63 publications