title: A critical component of meiotic drive in Neurospora is located near a chromosome rearrangement.
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 (Sk(S)) 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-2(INS1)) and part of a >220-kb inversion (Sk-2(INV1)). 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.
authors.affiliation: School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
authors.forename: Austin M
authors.initials: AM
authors.lastname: Harvey
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211.
authors.forename: David G
authors.initials: DG
authors.lastname: Rehard
authors.affiliation: School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
authors.forename: Katie M
authors.initials: KM
authors.lastname: Groskreutz
authors.affiliation: School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
authors.forename: Danielle R
authors.initials: DR
authors.lastname: Kuntz
authors.affiliation: School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Sharp
authors.affiliation: Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211.
authors.forename: Patrick K T
authors.initials: PK
authors.lastname: Shiu
authors.affiliation: School of Biological Sciences, Illinois State University, Normal, Illinois 61790 tmhammo@ilstu.edu.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Hammond
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D015825:Chromosomes, Fungal / Q000235:genetics*; D004271:DNA, Fungal / Q000235:genetics; D015321:Gene Rearrangement; D005800:Genes, Fungal; D056426:Genetic Loci; D008540:Meiosis; D008969:Molecular Sequence Data; D009154:Mutation; D009491:Neurospora / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal / Q000235:genetics
chemical_list: D004271:DNA, Fungal
keywords: Spore killer; genome sequencing and mapping; meiosis; meiotic drive; selfish elements