title: Dissimilar evolutionary histories of two resistance gene families in the genus Solanum.
abstract: Genomic analyses have shown that most genes in eukaryotic lineages belong to families. Gene families vary in terms of number of members, nucleotide similarity, gene integrity, expression, and function. Often, the members of gene families are arranged in clusters, which contribute to maintaining similarity among gene copies and also to generate duplicates through replication errors. Gene families offer us an opportunity to examine the forces involved in the evolution of the genomes and to study recombination events and genomic rearrangements. In this work, we focused on the evolution of two plant resistance gene families, Sw5 and Mi-1, and analyzed the completely sequenced nuclear genomes of potato and tomato. We first noticed that the potato genome carries larger resistance gene families than tomato, but all gene copies are pseudogenes. Second, phylogenetic analyses indicated that Sw5 and Mi-1 gene families had dissimilar evolutionary histories. In contrast to Sw5, Mi-1 homologues suffered repeated gene conversion events among the gene copies, particularly in the tomato genome.
authors.affiliation: a IBAM, Facultad de Ciencias Agrarias, CONICET, Universidad Nacional de Cuyo, Almirante Brown 500, M5528AHB, Chacras de Coria, Argentina.
authors.forename: Diana María
authors.initials: DM
authors.lastname: Segura
authors.affiliation: a IBAM, Facultad de Ciencias Agrarias, CONICET, Universidad Nacional de Cuyo, Almirante Brown 500, M5528AHB, Chacras de Coria, Argentina.
authors.forename: Ricardo Williams
authors.initials: RW
authors.lastname: Masuelli
authors.affiliation: a IBAM, Facultad de Ciencias Agrarias, CONICET, Universidad Nacional de Cuyo, Almirante Brown 500, M5528AHB, Chacras de Coria, Argentina.|b Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina.
authors.forename: M Virginia
authors.initials: MV
authors.lastname: Sanchez-Puerta
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D019143:Evolution, Molecular; D018628:Gene Dosage; D017343:Genes, Plant; D018551:Solanum lycopersicum / Q000145:classification / Q000235:genetics; D005810:Multigene Family; D010802:Phylogeny; D011544:Pseudogenes; D032322:Solanum / Q000145:classification / Q000235:genetics*; D011198:Solanum tuberosum / Q000145:classification / Q000235:genetics
keywords: Mi-1; Solanum; Sw5; evolution; resistance; résistance; évolution