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Title: Natural Selection, Intracellular Bottlenecks of Virus Populations, and Viral Superinfection Exclusion
Natural selection acts on cellular organisms by ensuring the genes responsible for an advantageous phenotype consistently reap the phenotypic advantage. This is possible because reproductive cells of these organisms are almost always haploid, separating the beneficial gene from its rival allele at every generation. How natural selection acts on plus-strand RNA viruses is unclear because these viruses frequently load host cells with numerous genome copies and replicate thousands of progeny genomes in each cell. Recent studies suggest that these viruses encode the Bottleneck, Isolate, Amplify, Select (BIAS) mechanism that blocks all but a few viral genome copies from replication, thus creating the environment in which the bottleneck-escaping viral genome copies are isolated from each other, allowing natural selection to reward beneficial mutations and purge lethal errors. This BIAS mechanism also blocks the genomes of highly homologous superinfecting viruses, thus explaining cellular-level superinfection exclusion.  more » « less
Award ID(s):
1758912
PAR ID:
10374227
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Annual Review of Virology
Volume:
9
Issue:
1
ISSN:
2327-056X
Page Range / eLocation ID:
121 to 137
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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