A mutated swi4 gene causes duplications in the mating-type region of Schizosaccharomyces pombe

  title={A mutated swi4 gene causes duplications in the mating-type region of Schizosaccharomyces pombe},
  author={Oliver Fleck and Lutz Heim and Herbert Gutz},
  journal={Current Genetics},
SummaryEfficient mating-type (MT) switching in homothallic strains of Schizosaccharomyces pombe is significantly reduced if they have a mutation in any of the eleven known swi genes. The swi4 mutation causes heterothallic as well as homothallic segregants, both of which have duplications in the MT region. In contrast to homothallic strains, h+swi4 strains yield only a few duplications. The duplications originate in the process of MT switching, presumably by mistakes in the resolution of DNA… 

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    Proceedings of the National Academy of Sciences of the United States of America
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The fission yeast Schizosaccharomyces pombe switches mating type by transposition of a copy of DNA derived from either of the two storage cassettes, mat2 -P and mat3 -M, into the expression locus,
Gene activation by copy transposition in mating-type switching of a homothallic fission yeast
Mating-type switching in homothallic clones of the fission yeast, Schizosaccharomyces pombe, appears to follow the same route as previously found for “mutations” from homothallism to heterothallic ⊕ strains, but the unlinked mutations are recessive to their wild-type alleles.
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