title: Endosperm-based postzygotic hybridization barriers: developmental mechanisms and evolutionary drivers.
abstract: The endosperm is a nourishing tissue that serves to support embryo growth. Failure of endosperm development will ultimately cause embryo arrest and seed lethality, a phenomenon that is frequently observed upon hybridization of related plant species or species that differ in ploidy. Endosperm-based interspecies or interploidy hybridization barriers depend on the direction of the hybridization, causing nonreciprocal seed defects. This reveals that the parental genomes are not equivalent, implicating parent-of-origin specific genes generating this type of hybridization barrier. Recent work revealed that endosperm-based hybridization barriers are rapidly evolving. In this review, we discuss the developmental mechanisms causing hybrid seed lethality in angiosperms as well as the evolutionary forces establishing endosperm-based postzygotic hybridization barriers.
authors.affiliation: Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 750 07, Uppsala, Sweden.
authors.forename: Clément
authors.initials: C
authors.lastname: Lafon-Placette
authors.affiliation: Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 750 07, Uppsala, Sweden.
authors.forename: Claudia
authors.initials: C
authors.lastname: Köhler
mesh_terms: D005075:Biological Evolution; D056625:Endosperm / Q000235:genetics*; D018628:Gene Dosage; D018392:Genomic Imprinting; D006824:Hybridization, Genetic; D019684:Magnoliopsida / Q000235:genetics*; D011003:Ploidies; D060047:Reproductive Isolation
keywords: endosperm; genetic value; genomic imprinting; parental conflict; postzygotic hybridization barrier