小麦条锈菌II类几丁质合成酶基因PstChsII的克隆及表达特征

摘要:【目的】克隆小麦条锈菌几丁质合成酶基因PstChsII，分析其在小麦条锈菌不同发育时期的表达水平。【方法】利用RT-PCR和PCR技术克隆PstChsII的cDNA序列和基因组序列，利用不同的生物信息学软件对序列进行分析，运用实时荧光定量技术分析基因在孢子、芽管以及不同侵染时间的表达水平。【结果】PstChsII基因（Genbank登录号GQ329851）编码区存在15个内含子，开放阅读框长2727 bp，编码908个氨基酸。PstChsII蛋白C端含有7个跨膜螺旋区，N端含多个保守结构域和“QXR

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

Objective]To clone the chitin synthase gene PstChs II from Puccinia striiformis and to analyze its expression pattern.Methods]We isolated the cDNA and genomic DNA of PstChs II 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 PstChs II (Genbank accession no:GQ32985l),interrupted by 15 introns,corresponded to a 2727 bp open reading frame encoding 908 amino acids. PstChs Ⅱ showed a highest 94 % similarity to PgtChs II from Puccinia graminis . PstChs II had 7 transmembrance regions and several conserved chitin synthase domains and motifs such as "QXRRW" ,"GXGPL"and "DXD" . PstChs Ⅱ belonged to the class E sub-family and had a closer phylogenetic relationship to its homologs from basidiomycetes than those from ascomycetes. PstChs Ⅱ expression level increased by 10-fold at the urediospore germination stage.Conclusion]PstChs Ⅱ might be involved in the cell wall synthesis during the germ tube elongation process. The cloning and expression analysis of PstChs II served as a good foundation for further analyzing the role of this gene in the pathogenesis process.