Skip to main content

A conservative test of genetic drift in the endosymbiotic bacterium Buchnera: slightly deleterious mutations in the chaperonin groEL.

Publication ,  Journal Article
Herbeck, JT; Funk, DJ; Degnan, PH; Wernegreen, JJ
Published in: Genetics
December 2003

The obligate endosymbiotic bacterium Buchnera aphidicola shows elevated rates of sequence evolution compared to free-living relatives, particularly at nonsynonymous sites. Because Buchnera experiences population bottlenecks during transmission to the offspring of its aphid host, it is hypothesized that genetic drift and the accumulation of slightly deleterious mutations can explain this rate increase. Recent studies of intraspecific variation in Buchnera reveal patterns consistent with this hypothesis. In this study, we examine inter- and intraspecific nucleotide variation in groEL, a highly conserved chaperonin gene that is constitutively overexpressed in Buchnera. Maximum-likelihood estimates of nonsynonymous substitution rates across Buchnera species are strikingly low at groEL compared to other loci. Despite this evidence for strong purifying selection on groEL, our intraspecific analysis of this gene documents reduced synonymous polymorphism, elevated nonsynonymous polymorphism, and an excess of rare alleles relative to the neutral expectation, as found in recent studies of other Buchnera loci. Comparisons with Escherichia coli generally show patterns predicted by their differences in N(e). The sum of these observations is not expected under relaxed or balancing selection, selective sweeps, or increased mutation rate. Rather, they further support the hypothesis that drift is an important force driving accelerated protein evolution in this obligate mutualist.

Duke Scholars

Altmetric Attention Stats
Dimensions Citation Stats

Published In

Genetics

DOI

EISSN

1943-2631

ISSN

0016-6731

Publication Date

December 2003

Volume

165

Issue

4

Start / End Page

1651 / 1660

Related Subject Headings

  • Symbiosis
  • Selection, Genetic
  • Mutation
  • Molecular Sequence Data
  • Genetic Variation
  • Genetic Drift
  • Evolution, Molecular
  • Developmental Biology
  • Chaperonin 60
  • Buchnera
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Herbeck, J. T., Funk, D. J., Degnan, P. H., & Wernegreen, J. J. (2003). A conservative test of genetic drift in the endosymbiotic bacterium Buchnera: slightly deleterious mutations in the chaperonin groEL. Genetics, 165(4), 1651–1660. https://doi.org/10.1093/genetics/165.4.1651
Herbeck, Joshua T., Daniel J. Funk, Patrick H. Degnan, and Jennifer J. Wernegreen. “A conservative test of genetic drift in the endosymbiotic bacterium Buchnera: slightly deleterious mutations in the chaperonin groEL.Genetics 165, no. 4 (December 2003): 1651–60. https://doi.org/10.1093/genetics/165.4.1651.
Herbeck, Joshua T., et al. “A conservative test of genetic drift in the endosymbiotic bacterium Buchnera: slightly deleterious mutations in the chaperonin groEL.Genetics, vol. 165, no. 4, Dec. 2003, pp. 1651–60. Epmc, doi:10.1093/genetics/165.4.1651.

Published In

Genetics

DOI

EISSN

1943-2631

ISSN

0016-6731

Publication Date

December 2003

Volume

165

Issue

4

Start / End Page

1651 / 1660

Related Subject Headings

  • Symbiosis
  • Selection, Genetic
  • Mutation
  • Molecular Sequence Data
  • Genetic Variation
  • Genetic Drift
  • Evolution, Molecular
  • Developmental Biology
  • Chaperonin 60
  • Buchnera