泡桐NLR基因家族分析及其对植原体的响应

Analysis of Paulownia NLR Gene Family and their Responses to Phytoplasmas

为研究PfNLR基因家族在白花泡桐抗丛枝病过程中的作用,运用生物信息学方法全面分析了白花泡桐NLR(PfNLR)家族成员的组成、理化性质、染色体定位、进化、结构、顺式作用元件和组织表达特异性,结合植原体侵染白花泡桐前后的miRNA和转录组的表达量变化,筛选出与抗丛枝病相关的基因。结果表明:白花泡桐中的199个PfNLRs分属6个亚家族;91.9%的PfNLRs定位在白花泡桐18条染色体上,其中62.8%呈簇状分布,23个PfNLRs发生了10次染色体片段重复事件和1次染色体串联重复事件;PfNLR含激素类和胁迫类元件;miRNA和转录组的关联分析发现泡桐miRNA与PfNLR之间存在156对靶向关系;大多数PfNLRs在芽和根中表达;16个PfNLRs在白花泡桐感染植原体前后的表达水平显著差异。进一步分析发现,pf–miRNA482介导的PfNLR181在白花泡桐抗丛枝病中发挥作用,该结果可为解析白花泡桐NLR蛋白的功能提供理论依据。

In order to study the role of PfNLR gene family in Paulownia fortunei resistance to Paulownia witches' broom(PaWB),bioinformatics methods were used to comprehensively analyze the composition,physicochemical properties,chromosomal localization,evolution,structure,cis-acting elements and tissue expression specificity of P.fortunei NLR(PfNLR) family members.Combined with the miRNA and transcriptome data before and after phytoplasma infecting Paulownia,the genes associated with resistance to PaWB were screened.The results showed that 199 PfNLRs in P.fortunei belonged to 6 subfamilies;91.9% of PfNLRs were located on 18 chromosomes of P.fortunei,of which 62.8% were clustered,among them,there were 10 chromosome segment repeats and 1 chromosome tandem repeats in 23 PfNLRs;PfNLR contains hormonal and stress elements;integrated transcriptome and miRNA analysis found that there were 156 pairs of targeted relationships between PfNLRs and miRNAs;most of PfNLRs were expressed in buds and roots;of which,16 PfNLRs were significantly different before and after phytoplasma infection.Further analysis revealed that PfNLR181 mediated by pf-miRNA482 played a role in resistance of PaWB.These results could provide a theoretical basis for analyzing the function of PfNLR protein.