title: Variation and phylogeny of Fusarium oxysporum isolates based on nucleotide sequences of polygalacturonase genes.
abstract: The nucleotide sequences of two endopolygalacturonase genes (pg1 and pg5) and two exopolygalacturonase genes (pgx1 and pgx4), which encode members of a major family of secreted cell-wall-degrading enzymes (CWDEs), were compared to detect the extent of genetic variation among isolates of Fusarium oxysporum. The nucleotide variation rate in exons was 0.23-0.93%, higher than that in introns (0.01-0.64%) and untranslated regions (UTRs) (0.07-0.25%), resulting in 0.05-0.31% variation in amino acids. pgx1 exhibited the most genetic diversity. Phylogenetic analysis of the four genes, which reside on different chromosomes, revealed different evolutionary patterns for each. Our results suggest a biased evolution of the polygalacturonase genes of F. oxysporum, or alternatively, that the genes were acquired at different times during evolution.
authors.affiliation: Saitama Prefectural Agriculture and Forestry Research Center, 91 Rokumanbu, Kuki, Saitama 346-0037, Japan. a1057333@pref.saitama.1g.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hirano
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Arie