title: 2μ plasmid in Saccharomyces species and in Saccharomyces cerevisiae.
abstract: We determined that extrachromosomal 2μ plasmid was present in 67 of the Saccharomyces cerevisiae 100-genome strains; in addition to variation in the size and copy number of 2μ, we identified three distinct classes of 2μ. We identified 2μ presence/absence and class associations with populations, clinical origin and nuclear genotypes. We also screened genome sequences of S. paradoxus, S. kudriavzevii, S. uvarum, S. eubayanus, S. mikatae, S. arboricolus and S. bayanus strains for both integrated and extrachromosomal 2μ. Similar to S. cerevisiae, we found no integrated 2μ sequences in any S. paradoxus strains. However, we identified part of 2μ integrated into the genomes of some S. uvarum, S. kudriavzevii, S. mikatae and S. bayanus strains, which were distinct from each other and from all extrachromosomal 2μ. We identified extrachromosomal 2μ in one S. paradoxus, one S. eubayanus, two S. bayanus and 13 S. uvarum strains. The extrachromosomal 2μ in S. paradoxus, S. eubayanus and S. cerevisiae were distinct from each other. In contrast, the extrachromosomal 2μ in S. bayanus and S. uvarum strains were identical with each other and with one of the three classes of S. cerevisiae 2μ, consistent with interspecific transfer.
authors.affiliation: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Pooja K
authors.initials: PK
authors.lastname: Strope
authors.affiliation: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Stanislav G
authors.initials: SG
authors.lastname: Kozmin
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Skelly
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Magwene
authors.affiliation: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Fred S
authors.initials: FS
authors.lastname: Dietrich
authors.affiliation: Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA mccus001@mc.duke.edu.
authors.forename: John H
authors.initials: JH
authors.lastname: McCusker
mesh_terms: D014644:Genetic Variation; D020071:Interspersed Repetitive Sequences; D010957:Plasmids; D012440:Saccharomyces / Q000145:classification / Q000235:genetics*
keywords: 2-micron plasmid; 2μ plasmid; Saccharomyces cerevisiae; Saccharomyces genus; population genomics; selfish genetic elements