Format

Send to

Choose Destination
See comment in PubMed Commons below
Mol Phylogenet Evol. 2005 Nov;37(2):541-57. Epub 2005 Aug 24.

Phylogenetic relationships between members of the crucifer pathogenic Leptosphaeria maculans species complex as shown by mating type (MAT1-2), actin, and beta-tubulin sequences.

Author information

  • 1Lehrstuhl für Allgemeine Mikrobiologie and Mikrobengenetik,Pilz-Referenz-Zentrum, Friedrich-Schiller-Universität Jena, Neugasse 24, 07743 Jena, Germany.

Abstract

The dothideomycetous fungus Leptosphaeria maculans comprises a complex of species differing in specificity and pathogenicity on Brassica napus. Twenty-eight isolates were investigated and compared to 20 other species of the Pleosporales order. Sequences of the mating type MAT1-2 (23), fragments of actin (48) and beta-tubulin (45) genes were determined and used for phylogenetic analyses inferred by maximum parsimony, distance, maximum likelihood, and Bayesian approaches. These different approaches using single genes essentially confirmed findings using concatanated sequences. L. maculans formed a monophyletic group separate from Leptosphaeria biglobosa. The L. biglobosa clade encompasses five sub-clades; this finding is consistent with classification made previously on the basis of internal-transcribed sequences of the ribosomal DNA repeat. The propensity for purifying and neutral evolution of the three genes was determined using sliding window analysis, a technique not previously applied to genes of filamentous fungi. For members of the L. maculans species complex, this approach showed that in comparison to actin and beta-tubulin, exonic sequences of MAT1-2 were more diverse and appeared to evolve at a faster rate. However, different regions of MAT1-2 displayed different degrees of sequence conservation. The more conserved upstream region (including the High Mobility Group domain) may be better suited for interspecies differentiation, while the more diverse downstream region is more appropriate for intraspecies comparisons.

PMID:
16122948
DOI:
10.1016/j.ympev.2005.07.006
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center