Skip to main content

The role of capsid maturation on adenovirus priming for sequential uncoating.

Author(s): Pérez-Berná, Ana J; Ortega-Esteban, Alvaro; Menéndez-Conejero, Rosa; Winkler, Dennis C; Menéndez, Margarita; et al

Download
To refer to this page use: http://arks.princeton.edu/ark:/88435/pr11r3n
Abstract: Adenovirus assembly concludes with proteolytic processing of several capsid and core proteins. Immature virions containing precursor proteins lack infectivity because they cannot properly uncoat, becoming trapped in early endosomes. Structural studies have shown that precursors increase the network of interactions maintaining virion integrity. Using different biophysical techniques to analyze capsid disruption in vitro, we show that immature virions are more stable than the mature ones under a variety of stress conditions and that maturation primes adenovirus for highly cooperative DNA release. Cryoelectron tomography reveals that under mildly acidic conditions mimicking the early endosome, mature virions release pentons and peripheral core contents. At higher stress levels, both mature and immature capsids crack open. The virus core is completely released from cracked capsids in mature virions, but it remains connected to shell fragments in the immature particle. The extra stability of immature adenovirus does not equate with greater rigidity, because in nanoindentation assays immature virions exhibit greater elasticity than the mature particles. Our results have implications for the role of proteolytic maturation in adenovirus assembly and uncoating. Precursor proteins favor assembly by establishing stable interactions with the appropriate curvature and preventing premature ejection of contents by tightly sealing the capsid vertices. Upon maturation, core organization is looser, particularly at the periphery, and interactions preserving capsid curvature are weakened. The capsid becomes brittle, and pentons are more easily released. Based on these results, we hypothesize that changes in core compaction during maturation may increase capsid internal pressure to trigger proper uncoating of adenovirus.
Publication Date: 12-Jul-2012
Citation: Pérez-Berná, Ana J, Ortega-Esteban, Alvaro, Menéndez-Conejero, Rosa, Winkler, Dennis C, Menéndez, Margarita, Steven, Alasdair C, Flint, S Jane, de Pablo, Pedro J, San Martín, Carmen. (2012). The role of capsid maturation on adenovirus priming for sequential uncoating.. The Journal of biological chemistry, 287 (37), 31582 - 31595. doi:10.1074/jbc.M112.389957
DOI: doi:10.1074/jbc.M112.389957
ISSN: 0021-9258
EISSN: 1083-351X
Pages: 1 - 15
Language: eng
Type of Material: Journal Article
Journal/Proceeding Title: The Journal of biological chemistry
Version: Final published version. Article is made available in OAR by the publisher's permission or policy.



Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.