Current Genetics

, Volume 43, Issue 6, pp 425–432 | Cite as

Unpaired genes do not silence their paired neighbors

  • Brandi L. Kutil
  • Kye-Yong Seong
  • Rodolfo AramayoEmail author
Research Article


During meiotic chromosome pairing, a loop of unpaired DNA induces the silencing of all paired and unpaired homologous DNA via meiotic silencing, an RNA-mediated post-transcriptional gene-silencing mechanism. To test the effect of unpaired DNA on adjacent genes, we constructed strains containing the DNA of a transformation marker integrated immediately downstream of the Ascospore maturation-1 (Asm-1) gene and tested whether this unpaired DNA silences asm-1+. We conclude that unpaired downstream DNA has no effect on Asm-1 expression during meiosis or ascospore development, which suggests that the silencing signal produced by unpaired DNA does not propagate onto adjacent paired regions.


Chromosome pairing RNA silencing Meiotic silencing Gene replacement Locus engineering 



We thank Robert J. Pratt for his critical review of the manuscript. This work was supported by United States Public Health Service grant GM58770 to R.A.


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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Brandi L. Kutil
    • 2
  • Kye-Yong Seong
    • 1
  • Rodolfo Aramayo
    • 1
    Email author
  1. 1.Department of Biology, College of ScienceTexas A&M UniversityCollege StationUSA
  2. 2.Department of Plant Pathology and Microbiology, College of AgricultureTexas A&M UniversityCollege StationUSA

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