Evolutionary Robustness of an Optimal Phenotype: Re-evolution of Lysis in a Bacteriophage Deleted for Its Lysin Gene

@article{Heineman2004EvolutionaryRO,
  title={Evolutionary Robustness of an Optimal Phenotype: Re-evolution of Lysis in a Bacteriophage Deleted for Its Lysin Gene},
  author={Richard H Heineman and Ian J Molineux and James J. Bull},
  journal={Journal of Molecular Evolution},
  year={2004},
  volume={61},
  pages={181-191}
}
Optimality models are frequently used to create expectations about phenotypic evolution based on the fittest possible phenotype. However, they often ignore genetic details, which could confound these expectations. We experimentally analyzed the ability of organisms to evolve towards an optimum in an experimentally tractable system, lysis time in bacteriophage T7. T7 lysozyme helps lyse the host cell by degrading its cell wall at the end of infection, allowing viral escape to infect new hosts… Expand
A common, non-optimal phenotypic endpoint in experimental adaptations of bacteriophage lysis time
TLDR
Several features of ST-1 adaptation show that lysis time is best understood as an output of multiple traits, rather than in isolation, which suggests that constraint and genetic details affect quantitative and even qualitative success of optimality predictions. Expand
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Evidence suggests that the model's failure ultimately stems from a violation of the trade-off, rather than a paucity of mutations, which suggests the importance of genetic details in experimental evolution of a trait for which an optimality model exists and in which genetic details can be studied. Expand
Layers of Evolvability in a Bacteriophage Life History Trait
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The evolvability of lysis was studied in bacteriophage T7, revealing hidden functional interactions and revealing a second level of evolutionary redundancy that resulted in a lower fitness and slower lysis than wild-type T7. Expand
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The results illustrate that parasites can adapt to specific transmission environments, and that this adaptation can impose costs on the subsequent ability to exploit host cells, potentially constraining durable parasites to lower virulence. Expand
MULTIPLE GENETIC PATHWAYS TO SIMILAR FITNESS LIMITS DURING VIRAL ADAPTATION TO A NEW HOST
TLDR
The fitness landscape allows multiple genetic paths to the same approximate fitness limit, and the existence and causes of fitness limits have ramifications to genome engineering, vaccine design, and “lethal mutagenesis” treatments to cure viral infections. Expand
Gene order constrains adaptation in bacteriophage T7.
TLDR
The premise that gene order is important to fitness and that wild-type fitness is not rapidly re-evolved in reorganized genomes is supported. Expand
Lysis time, optimality, and the genetics of evolution in a T7 phage model system
TLDR
Molecular and phenotypic responses to genomic and environmental perturbations through experimental evolution in T7 bacteriophage are explored and the ability of T7 to adapt to an optimum lysis time is tested. Expand
Optimality models of phage life history and parallels in disease evolution.
  • J. Bull
  • Biology, Medicine
  • Journal of theoretical biology
  • 2006
TLDR
The lysis time models show that the optimum is less sensitive to differences in host density than suggested by earlier analytical work, and can be extended to more general properties of infection, such as the evolution of virulence and tissue tropism. Expand
Evolutionary Recovery of a Recombinant Viral Genome
TLDR
The large magnitude of fitness recovery with relatively few mutations suggests that the fitness costs of hybridizations and horizontal gene exchanges between moderately diverged genomes can potentially be short-lived through compensatory evolution. Expand
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