In it for the long haul: evolutionary consequences of persistent endosymbiosis.

Journal Article (Review;Journal Article)

Phylogenetically independent bacterial lineages have undergone a profound lifestyle shift: from a free-living to obligately host-associated existence. Among these lineages, intracellular bacterial mutualists of insects are among the most intimate, constrained symbioses known. These obligate endosymbionts exhibit severe gene loss and apparent genome deterioration. Evolutionary theory provides a basis to link their unusual genomic features with shifts in fundamental mechanisms - selection, genetic drift, mutation, and recombination. This mini-review highlights recent comparative and experimental research of processes shaping ongoing diversification within these ancient associations. Recent work supports clear contributions of stochastic processes, including genetic drift and exceptionally strong mutational pressure, toward degenerative evolution. Despite possible compensatory mechanisms, genome degradation may constrain how persistent endosymbionts (and their hosts) respond to environmental fluctuations.

Full Text

Duke Authors

Cited Authors

  • Wernegreen, JJ

Published Date

  • December 2017

Published In

Volume / Issue

  • 47 /

Start / End Page

  • 83 - 90

PubMed ID

  • 28934627

Electronic International Standard Serial Number (EISSN)

  • 1879-0380

International Standard Serial Number (ISSN)

  • 0959-437X

Digital Object Identifier (DOI)

  • 10.1016/j.gde.2017.08.006


  • eng