Genes that bias Mendelian segregation.
Mendel laws of inheritance can be cheated by Meiotic Drive Elements (MDs), complex nuclear genetic loci found in various eukaryotic genomes and distorting segregation in their favor. Here, we identify and characterize in the model fungus Podospora anserina Spok1 and Spok2, two MDs known as Spore Killers. We show that they are related genes with both spore-killing distorter and spore-protecting responder activities carried out by the same allele. These alleles act as autonomous elements, exert their effects independently of their location in the genome and can act as MDs in other fungi. Additionally, Spok1 acts as a resistance factor to Spok2 killing. Genetical data and cytological analysis of Spok1 and Spok2 localization during the killing process suggest a complex mode of action for Spok proteins. Spok1 and Spok2 belong to a multigene family prevalent in the genomes of many ascomycetes. As they have no obvious cellular role, Spok1 and Spok2 Spore Killer genes represent a novel kind of selfish genetic elements prevalent in fungal genome that proliferate through meiotic distortion.
Univ Paris Diderot, Sorbonne Paris Cité, Institut des Energies de Demain, Paris, France; Univ Paris Sud, Institut de Génétique et Microbiologie, Bât. 400, Orsay, France.
Pierre
P
Grognet
Univ Paris Diderot, Sorbonne Paris Cité, Institut des Energies de Demain, Paris, France; Univ Paris Sud, Institut de Génétique et Microbiologie, Bât. 400, Orsay, France.
Hervé
H
Lalucque
Univ Paris Diderot, Sorbonne Paris Cité, Institut des Energies de Demain, Paris, France; Univ Paris Sud, Institut de Génétique et Microbiologie, Bât. 400, Orsay, France.
Fabienne
F
Malagnac
Univ Paris Diderot, Sorbonne Paris Cité, Institut des Energies de Demain, Paris, France; Univ Paris Sud, Institut de Génétique et Microbiologie, Bât. 400, Orsay, France.
Philippe
P
Silar
D000483:Alleles; D020090:Chromosome Segregation / Q000235:genetics*; D003433:Crosses, Genetic; D005656:Fungal Proteins / Q000235:genetics*; D008540:Meiosis / Q000235:genetics*; D048468:Podospora / Q000235:genetics*; D013172:Spores, Fungal
D005656:Fungal Proteins