ISSN:
1432-1432
Keywords:
Saccharomyces cerevisiae
;
2-μm circle
;
DNA sequencing
;
Horizontal transmission
;
Site-specific recombination
;
Selfish DNA
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract We compared the nucleotide substitution pattern over the entire genome of two unique variants of the 6,300-bp selfish DNA (2 μm) plasmid in Saccharomyces cerevisiae. The DNA sequence of the left-unique region is identical among 2-μm variants, while the right-unique region shows substantial divergence. This chimeric pattern cannot be explained by neutral or Darwinian selection models. We propose that horizontal transmission of the 2-μm plasmid coupled with a directed, polarized gene conversion maintains the DNA sequence of the left-unique region, whereas the right-unique region is subject to random drift and Darwinian selection.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00163153
