title: Survey and expression analysis of five new chitin synthase genes in the biotrophic rust fungus Puccinia graminis.
abstract: We have isolated and characterised the first set of chitin synthase genes from a rust fungus, a large group of economically highly important, obligately biotrophic plant pathogens. Puccinia graminis was used as a model organism for the rust fungi which are not well investigated on the molecular level today. One of the major structural components of most fungal cell walls is the chitin polymer which is synthesised by a family of enzymes called chitin synthases. In P. graminis, we have isolated five new chitin synthase genes from four different classes, chsII, chsIIIa, chsIIIb, chsIV, and chsV. The genes contain a high number of introns, unusual for other known fungal chitin synthases. The dinucleic stage of the fungus seems to contain two slightly different genes or alleles for four isoforms. One isoform, chsIIIa, seems to be expressed only in the youngest stages of fungal growth. Analysis of the derived proteins shows that together with other basidiomycete CHS, the pgtCHS form separate subgroups in the phylogenetic tree. This set of five rust chitin synthase genes, with some unusual features compared to known fungal chitin synthases, allows new insights into chitin synthase classification, and may help in the development of novel functional fungicides.
authors.affiliation: Institut für Biochemie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität Münster, Münster, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Broeker
authors.forename: Sabine
authors.initials: S
authors.lastname: Fehser
authors.forename: Bruno M
authors.initials: BM
authors.lastname: Moerschbacher
mesh_terms: D001487:Basidiomycota / Q000201:enzymology* / Q000235:genetics; D002687:Chitin Synthase / Q000235:genetics* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D008957:Models, Genetic; D010802:Phylogeny; D017421:Sequence Analysis; D014908:Triticum / Q000382:microbiology
chemical_list: D005656:Fungal Proteins; D002687:Chitin Synthase