The SNAP hypothesis: Chromosomal rearrangements could emerge from positive Selection during Niche Adaptation.

ABSTRACT: The relative linear order of most genes on bacterial chromosomes is not conserved over evolutionary timescales. One explanation is that selection is weak, allowing recombination to randomize gene order by genetic drift. However, most chromosomal rearrangements are deleterious to fitness. In contrast, we propose the hypothesis that rearrangements in gene order are more likely the result of selection during niche adaptation (SNAP). Partial chromosomal duplications occur very frequently by recombination between direct repeat sequences. Duplicated regions may contain tens to hundreds of genes and segregate quickly unless maintained by selection. Bacteria exposed to non-lethal selections (for example, a requirement to grow on a poor nutrient) can adapt by maintaining a duplication that includes

SUBMITTER: Brandis G 

PROVIDER: S-EPMC7055797 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature