Cloning and expression of a class II chitin synthase gene PstChsII from the rust fungus Puccinia striiformi

Abstract:

Abstract: [Objective] To clone the chitin synthase gene PstChsII from Puccinia striiformis and to analyze its expression pattern. [Methods] We isolated the cDNA and genomic DNA of PstChsII via RT-PCR and PCR, analyzed the sequences with different bioinformatic tools, characterized the gene expression pattern via real-time PCR. [Results] The coding region of PstChsII (Genbank accession no: GQ329851), interrupted by 15 introns, corresponded to a 2727 bp open reading frame encoding 908 amino acids. PstChsII showed a highest 94% similarity to PgtChsII from Puccinia graminis. PstChsII had 7 transmembrance regions and several conserved chitin synthase domains and motifs such as “QXRRW”,“GXGPL”and “DXD”. PstChsII belonged to the class II sub-family and had a closer phylogenetic relationship to its homologs from basidiomycetes than those from ascomycetes. PstChsII expression level increased by 10-fold at the urediospore germination stage. [Conclusion] PstChsII might be involved in the cell wall synthesis during the germ tube elongation process. The cloning and expression analysis of PstChsII served as a good foundation for further analyzing the role of this gene in the pathogenesis process.