Originally published as Genetics Published Articles Ahead of Print on August 24, 2007.

Genetics, Vol. 177, 937-948, October 2007, Copyright © 2007
doi:10.1534/genetics.107.075663

The Roles of Mutation Accumulation and Selection in Loss of Sporulation in Experimental Populations of Bacillus subtilis

Heather Maughan*,1, Joanna Masel*, C. William Birky, Jr.* and Wayne L. Nicholson{dagger}

* Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 and {dagger} Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida 32899

1 Corresponding author: Department of Zoology Life Sciences, Centre 2350, Health Sciences Mall, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
E-mail: maughan{at}zoology.ubc.ca

Phenotypic loss is an important evolutionary force in nature but the mechanism(s) responsible for loss remains unclear. We used both simulation and multiple-regression approaches to analyze data on the loss of sporulation, a complex bacterial developmental process, during experimental evolution of Bacillus subtilis. Neutral processes of mutational degradation alone were sufficient to explain loss-of-sporulation ability in four of five populations, while evidence that selection facilitated mutational loss was found for only one population. These results are discussed in the context of the evolution of sporulation in particular and phenotypic loss in general.


Related articles in Genetics:

ISSUE HIGHLIGHTS

Genetics 2007 177: NP. [Full Text]