【目的】克隆条锈菌诱导的小麦病程相关蛋白PR10基因,研究其在小麦成株抗条锈病防御反应中的作用。【方法】采用电子克隆、RT—PCR技术,从条锈菌侵染的小麦兴资9104中,分离病程相关蛋白10基因;采用生物信息学技术预测分析该基因的DNA序列结构及其编码蛋白的保守域及基本特性;利用实时荧光定量RT—PCR技术,分析该基因在小麦成株期和苗期受条锈菌CYR32侵染后的表达情况。【结果】分离到病程相关蛋白10基因,命名为TaPR10,ORF长483bp,编码由160个氨基酸组成的蛋白质TaPR10;TaPR10不含跨膜区、无信号肽、定位在胞内,除具有典型的病程相关蛋白Bet_v_I家族保守结构域外,还有其它4类功能保守域;与小麦、高粱、玉米和水稻等4种植物PR10蛋白的氨基酸序列相似性在80%左右;TaPg10 DNA序列内部存在188至271位84bp的内含子序列,其拼接位点序列具有GT—AG双核苷酸序列;TaPR10基因表达分析的结果表明,TaPR10基因在成株期和苗期反应中表达量均上调,成株期表达高于苗期。[结论]首次分离到一个条锈菌CYR32诱导的小麦TaPR10基因,该基因可能参与了小麦成株抗条锈病防御反应。
[Objective] A stripe rust pathogen induced PR10 gene from wheat was isolated to better understand adult wheat resistance response. [Method] In silico cloning and RT-PCR techniques were performed to isolate a PRIO gene in wheat induced by stripe rust pathogen. Its DNA sequence structure and conserved domain of encoding protein with basic properties were determined using bioinformatics analysis. The expression patterns of the gene during adult and seedling stage of wheat infected by stripe rust pathogen were investigated using real time quantitative RT-PCR. [Result] The PR10 gene designated as TaPR10 was obtained from wheat inoculated with stripe rust pathogen. Open reading frame (ORF) of TaPR10 was 483bp in length, encoding 160 amino acids containing one typical conserved domain of pathogenesis related protein Bet_v_I family, and other four kinds of conserved motifs. TaPR10, without trans-membrane domain or signal peptide sequences, was predicted to locate in cytosol. Multiple alignment analysis based on the amino acids encoded by different PRIO genes from Maize (Zea mays), rice (Oryza sativa), broomcorn (Sorghum bicolor) and wheat (Triticum aestivum) indicated that PR10 was conserved among the four species of plants with about 80% of sequence similarity. DNA sequence of TaPR10 showed that it contained one 84 bp intron with the splicing sites of GT-AT bi-nucleotide sequence between 188 bp and 271 bp. Expression pattern results revealed that TaPR10 was up regulated in both of adult and seedling stages. However, expression in adult stage was higher than that of seedling stage. [Conclusion] Gene TaPR10 was firstly isolated and characterized from wheat infected by stripe rust pathogen, which may participate in defense response of adult wheat resistance to stripe rust pathogen.