title: Efficient purging of deleterious mutations in plants with haploid selfing.
abstract: In diploid organisms, selfing reduces the efficiency of selection in removing deleterious mutations from a population. This need not be the case for all organisms. Some plants, for example, undergo an extreme form of selfing known as intragametophytic selfing, which immediately exposes all recessive deleterious mutations in a parental genome to selective purging. Here, we ask how effectively deleterious mutations are removed from such plants. Specifically, we study the extent to which deleterious mutations accumulate in a predominantly selfing and a predominantly outcrossing pair of moss species, using genome-wide transcriptome data. We find that the selfing species purge significantly more nonsynonymous mutations, as well as a greater proportion of radical amino acid changes which alter physicochemical properties of amino acids. Moreover, their purging of deleterious mutation is especially strong in conserved regions of protein-coding genes. Our observations show that selfing need not impede but can even accelerate the removal of deleterious mutations, and do so on a genome-wide scale.
authors.affiliation: Institute of Evolutionary Biology and Environmental Studies, University of Zurich, SwitzerlandInstitute of Systematic Botany, University of Zurich, SwitzerlandSwiss Institute of Bioinformatics, Quartier Sorge-Batiment Genopode, Lausanne, SwitzerlandMTA-ELTE-MTM Ecology Research Group, ELTE, Biological Institute, Hungary peter.szoevenyi@uzh.ch.
authors.forename: Péter
authors.initials: P
authors.lastname: Szövényi
authors.affiliation: Department of Biology, Duke University.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Devos
authors.affiliation: Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN.
authors.forename: David J
authors.initials: DJ
authors.lastname: Weston
authors.affiliation: Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN.
authors.forename: Xiaohan
authors.initials: X
authors.lastname: Yang
authors.affiliation: Institute of Systematic Botany, University of Zurich, Switzerland.
authors.forename: Zsófia
authors.initials: Z
authors.lastname: Hock
authors.affiliation: Department of Biology, Duke University.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Shaw
authors.affiliation: Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Switzerland.
authors.forename: Kentaro K
authors.initials: KK
authors.lastname: Shimizu
authors.affiliation: Biology Department, University of Florida.
authors.forename: Stuart F
authors.initials: SF
authors.lastname: McDaniel
authors.affiliation: Institute of Evolutionary Biology and Environmental Studies, University of Zurich, SwitzerlandSwiss Institute of Bioinformatics, Quartier Sorge-Batiment Genopode, Lausanne, SwitzerlandBioinformatics Institute, Agency for Science, Technology and Research (A*STAR), SingaporeThe Santa Fe Institute, Santa Fe NM.
authors.forename: Andreas
authors.initials: A
authors.lastname: Wagner
mesh_terms: D001483:Base Sequence; D005075:Biological Evolution; D044002:Bryophyta / Q000235:genetics*; D017124:Conserved Sequence; D004171:Diploidy; D006238:Haploidy; D059014:High-Throughput Nucleotide Sequencing; D009154:Mutation; D054817:Pollination; D012641:Selection, Genetic; D057945:Self-Fertilization; D059467:Transcriptome
keywords: deleterious mutations; diploid; haploid; haploid-dominant life cycle; high throughput sequencing; intragametophytic selfing; outcrossing