PHLOEM PROMOTERS IN TRANSGENIC SWEET ORANGE ARE DIFFERENTIALLY TRIGGERED BY Candidatus Liberibacter asiaticus
PHLOEM PROMOTERS IN TRANSGENIC SWEET ORANGE ARE DIFFERENTIALLY TRIGGERED BY Candidatus Liberibacter asiaticus
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DOI：
10.1590/0100-29452017993
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发表时间：
2017-08-01
影响因子：
1
通讯作者：
MOURÃO FILHO, FRANCISCO DE ASSIS ALVES
中科院分区：
文献类型：
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作者：
MIYATA, LUZIA YURIKO;HARAKAVA, RICARDO;MOURÃO FILHO, FRANCISCO DE ASSIS ALVES
使用在特定植物组织中优先表达的启动子是寻找对定殖这些组织的病原体的抗性的理想策略。柑橘黄龙病病原菌亚洲黄龙杆菌（Las）在韧皮部导管中定植。一些启动子除了赋予组织特异性表达外，还可以响应病原体的存在。本研究的目的是验证Las的存在是否可以调节韧皮部特异性启动子AtPP 2（拟南芥韧皮部蛋白2）、AtSUC 2（拟南芥）的激活。thaliana蔗糖转运蛋白2）和CsPP 2（柑橘韧皮部蛋白2），已知在柑橘韧皮部中表达。哈姆林甜橙子（Citrus sinensis L.）Osbeck）、AtSUC 2和CsPP 2启动子控制下的uidA（GUS）报告基因转化，以评估转基因表达与Las浓度之间的相互依赖性。用柑橘木虱的Las接种植株，18个月后，分别通过qPCR和RT-qPCR测定细菌浓度和uidA表达。由AtSUC 2启动子驱动的报告基因表达与Las浓度强烈正相关。因此，该启动子结合了组织特异性和病原体诱导性的理想特征，用于产生对Las耐受的转基因植物。
The use of promoters preferentially expressed in specific plant tissues is a desirable strategy to search for resistance for pathogens that colonize these tissues. The bacterium Candidatus Liberibacter asiaticus (Las), associated with huanglongbing disease (HLB) of citrus, colonizes phloem vessels. Some promoters, besides conferring tissue-specific expression, can also respond to the presence of the pathogen. The objective of the present study was to verify if the presence of Las could modulate the activation of the phloem-specific promoters AtPP2 (Arabidopsis thaliana phloem protein 2), AtSUC2 (A. thaliana sucrose transporter 2) and CsPP2 (Citrus phloem protein 2), known to be expressed in Citrus sinensis phloem. 'Hamlin' sweet orange plants (Citrus sinensis L. Osbeck) transformed with the uidA (GUS) reporter gene under the control of AtPP2, AtSUC2 and CsPP2 promoters were infected to evaluate the interdependence between transgene expression and the concentration of Las. Plants were inoculated with Las by Diaphorina citri and eighteen months later, bacterial concentration and uidA expression were determined by qPCR and RT-qPCR, respectively. Reporter gene expression driven by AtSUC2 promoter was strongly and positively correlated with Las concentration. Therefore, this promoter combines desirable features of both tissue-specificity and pathogen-inducibility for the production of transgenic plants tolerant to Las.