Frey María Eugenia, D'Ippolito Sebastián, Pepe Alfonso, Daleo Gustavo Raúl, Guevara María Gabriela
Biological Research Institute, National Council of Scientific and Technique Research (CONICET), University of Mar del Plata, Mar del Plata (UNMDP), Argentina.
Biological Research Institute, National Council of Scientific and Technique Research (CONICET), University of Mar del Plata, Mar del Plata (UNMDP), Argentina.
Phytochemistry. 2018 May;149:1-11. doi: 10.1016/j.phytochem.2018.02.004. Epub 2018 Feb 8.
The plant-specific insert of Solanum tuberosum aspartic proteases (StAP-PSI) has high structural similarity with NK-lysin and granulysin, two saposin-like proteins (SAPLIPs) with antimicrobial activity. Recombinant StAP-PSI and some SAPLIPs show antimicrobial activity against pathogens that affect human and plants. In this work, we transformed Arabidopsis thaliana plants with StAP-PSI encoding sequence with its corresponding signal peptide under the control of the cauliflower mosaic virus (CaMV) 35S promoter. Results obtained show that StAP-PSI significantly enhances Arabidopsis resistance against Botrytis cinerea infection. StAP-PSI is secreted into the leaf apoplast and acts directly against pathogens; thereby complementing plant innate immune responses. Data obtained from real-time PCR assays show that the constitutive expression of StAP-PSI induces the expression of genes that regulate jasmonic acid signalling pathway, such as PDF1.2, in response to infection due to necrotrophic pathogens. On the other hand, according to the data described for other antimicrobial peptides, the presence of the StAP-PSI protein in the apoplast of A. thaliana leaves is responsible for the expression of salicylic acid-associated genes, such as PR-1, irrespective of infection with B. cinerea. These results indicate that the increased resistance demonstrated by A. thaliana plants that constitutively express StAP-PSI owing to B. cinerea infection compared to the wild-type plants is a consequence of two factors, i.e., the antifungal activity of StAP-PSI and the overexpression of A. thaliana defense genes induced by the constitutive expression of StAP-PSI. We suggest that the use of this protein would help in minimizing the ecological and health risks that arise from the use of pesticides. We suggest that the use of this protein would help in minimizing the ecological and health risks that arise from the spreading of resistance of agriculturally important pathogens.
马铃薯天冬氨酸蛋白酶（StAP-PSI）的植物特异性插入片段与NK-溶素和颗粒溶素具有高度的结构相似性，这两种类鞘脂激活蛋白（SAPLIPs）具有抗菌活性。重组StAP-PSI和一些SAPLIPs对影响人类和植物的病原体具有抗菌活性。在这项工作中，我们用编码StAP-PSI的序列及其相应信号肽在花椰菜花叶病毒（CaMV）35S启动子的控制下转化拟南芥植株。获得的结果表明，StAP-PSI显著增强了拟南芥对灰霉病菌感染的抗性。StAP-PSI被分泌到叶质外体中并直接作用于病原体，从而补充植物的固有免疫反应。实时PCR分析获得的数据表明，StAP-PSI的组成型表达诱导了响应坏死营养型病原体感染而调节茉莉酸信号通路的基因（如PDF1.2）的表达。另一方面，根据针对其他抗菌肽描述的数据，拟南芥叶质外体中StAP-PSI蛋白的存在导致了水杨酸相关基因（如PR-1）的表达，而与是否感染灰霉病菌无关。这些结果表明，与野生型植株相比，组成型表达StAP-PSI的拟南芥植株因灰霉病菌感染而表现出的抗性增强是两个因素的结果，即StAP-PSI的抗真菌活性和StAP-PSI的组成型表达诱导的拟南芥防御基因的过表达。我们认为，使用这种蛋白质将有助于将因使用农药而产生的生态和健康风险降至最低。我们认为，使用这种蛋白质将有助于将因农业重要病原体抗性传播而产生的生态和健康风险降至最低。
