Mating-Type Genes from Asexual Phytopathogenic AscomycetesFusarium oxysporumandAlternaria alternata

Abstract

Mating-type (MAT) loci were cloned from two asexual (mitosporic) phytopathogenic ascomycetes, Fusarium oxysporum (a pyrenomycete) and Alternaria alternata (a loculoascomycete), by a polymerase chain reaction (PCR)-based strategy. The conserved high mobility group (HMG) box domain found in the MAT1-2-1 protein was used as a starting point for cloning and sequencing the entire MAT1-2 idiomorph plus flanking regions. Primer pairs designed to both flanking regions were used to amplify the opposite MAT1-1 idiomorph. The MAT1-1 and MAT1-2 idiomorphs were approximately 4.6 and 3.8 kb in F. oxysporum and approximately 1.9 and 2.2 kb in A. alternata, respectively. In both species, the MAT1-1 idiomorph contains at least one gene that encodes a protein with a putative alpha box domain and the MAT1-2 idiomorph contains one gene that encodes a protein with a putative HMG box domain. MAT-specific primers were used to assess the mating type of F. oxysporum and A. alternata field isolates by PCR. MAT genes from A. alternata were expressed. The A. alternata genes were confirmed to be functional in a close sexual relative, Cochliobolus heterostrophus, by heterologous expression.

Diverse sources of infection and cryptic recombination revealed in South African Diplodia pinea populations

“…This result is considered evidence of recombination as has been shown in other fungi (Geiser et al 1994;Arie et al 2000;Groenewald et al 2008;Pérez et al 2010). No sexual structures have been observed in D. pinea, despite the fact that it has been studied intensively for more than a century (Swart and Wingfield 1991).…”

Population structure and mating-type genes ofColletotrichum graminicolafromAgrostis palustris

“…These primers were designed by Arie et al (2000) to amplify MAT1 from Fusarium oxysporum and were also used by Steenkamp et al (2000) to amplify MAT1 from Gibberella fujikuroi. The PCR mix was the same as that for MAT2, except that the primers were used at 2 μM.…”

“…We also attempted to amplify MAT1 using the primers Falpha1 and Falpha2 (Arie et al 2000) under various PCR amplification conditions, but only very faint bands ranging in size from 200 to 400 bp were found. This was within the range of expected sizes, since MAT1 bands of 370 and 190 bp have been found for F. oxysporum and G. fujikuroi, respectively, but because the amplified bands were very faint and some PCR products were composed of multiple bands, we were unable to sequence these PCR products.…”

GMC oxidoreductase, a highly expressed protein in a potent biocontrol agent Fusarium oxysporum Cong:1-2, is dispensable for biocontrol activity

“…Protoplast preparation from F. oxysporum and polyethylene glycol (PEG) transformation were performed as described in Kawabe et al (2004) and Arie et al (2000), respectively. Briefl y, protoplasts were generated from fresh F. oxysporum mycelia by incubation in enzyme osmoticum containing 1% (w/v) lysing enzyme (Sigma, St. Louis, MO, USA), 1% (w/v) Driselase (Kyowa Hakko Kirin, Tokyo, Japan), and 0.0025% (w/v) chitinase (Wako Pure Chemical Industries, Tokyo, Japan).…”