1. A Critical Component of Meiotic Drive in Neurospora Is Located Near a Chromosome Rearrangement
- Author
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Patrick K. T. Shiu, David G. Rehard, Kevin J. Sharp, Thomas M. Hammond, Katie M. Groskreutz, Danielle R. Kuntz, and Austin M. Harvey
- Subjects
Genes, Fungal ,Molecular Sequence Data ,Locus (genetics) ,Chromosomal rearrangement ,Investigations ,Biology ,Neurospora ,Meiosis ,Genetics ,DNA, Fungal ,Gene Rearrangement ,Base Sequence ,fungi ,Chromosome Mapping ,Sequence Analysis, DNA ,Gene rearrangement ,Spores, Fungal ,biology.organism_classification ,Meiotic drive ,Genetic Loci ,Mutation ,Chromosomes, Fungal ,Recombination ,Genetic screen - Abstract
Neurospora fungi harbor a group of meiotic drive elements known as Spore killers (Sk). Spore killer-2 (Sk-2) and Spore killer-3 (Sk-3) are two Sk elements that map to a region of suppressed recombination. Although this recombination block is limited to crosses between Sk and Sk-sensitive (SkS) strains, its existence has hindered Sk characterization. Here we report the circumvention of this obstacle by combining a classical genetic screen with next-generation sequencing technology and three-point crossing assays. This approach has allowed us to identify a novel locus called rfk-1, mutation of which disrupts spore killing by Sk-2. We have mapped rfk-1 to a 45-kb region near the right border of the Sk-2 element, a location that also harbors an 11-kb insertion (Sk-2INS1) and part of a >220-kb inversion (Sk-2INV1). These are the first two chromosome rearrangements to be formally identified in a Neurospora Sk element, providing evidence that they are at least partially responsible for Sk-based recombination suppression. Additionally, the proximity of these chromosome rearrangements to rfk-1 (a critical component of the spore-killing mechanism) suggests that they have played a key role in the evolution of meiotic drive in Neurospora.
- Published
- 2014