Cloning and Evaluation of Receptor Gene for Host-selective ACR Toxin

宿主选择性ACR毒素受体基因的克隆与评价

基本信息

批准号：
11660048
负责人：
AKIMITSU Kazuya
金额：
$ 2.43万
依托单位：
Kagawa University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660048/
关键词：
ACR-toxin Alternaria Brown spot disease Citrus Host-specific toxin tRNA-Ala mitochondria receptor

项目摘要

Rough lemon is sensitive to host-selective toxin ACR-toxin and susceptible to its producer Alternaria alternata rough lemon pathotype. The target site of ACR-toxin is rough lemon mitochondrion, and the toxin has no effect on mitochondria from resistant plants. We have cloned a receptor gene, ACRS gene, which confers the toxin sensitivity by expressing in Escherichia coli cells. Coding region of the gene is located in the group II intron of tRNA-Ala in mitochondrial genome, and translates the pore-forming oligometric receptor to ACR-toxin. ACRS gene locates at mitochondrial genomes from both toxin-sensitive and insensitive citrus. However, the transcripts suffer a processing to be dysfunctional in toxin-insensitive citrus, while those in toxin-sensitive rough lemon remain intact without the processing. To determine whether ACRS is translated in mitochondria, proteins from isolated mitochondria of toxin-sensitive rough lemon and insensitive citrus were analyzed by western blot with anti-ACRS antibodies. The antibodies detected peptides on blot from only rough lemon mitochondria, while no peptides detected by the antibodies from any resistant citrus mitochondria tested. These results demonstrated that the post-transcriptional modification of this mitochondrial ACRS gene regulates specificity in the toxin-plant interactions, in which RNA processing in mitochondria plays a key role in controlling sensitivity to ACR-toxin in citrus.

粗糙的柠檬对宿主选择性毒素的杂毒素很敏感，并且对其生产者的替代品替代柠檬病病变敏感。 Acr-Toxin的目标部位是粗糙的柠檬线粒体，毒素对抗性植物的线粒体没有影响。我们已经克隆了一个受体基因ACRS基因，该基因通过在大肠杆菌细胞中表达毒素敏感性。该基因的编码区域位于线粒体基因组中tRNA-ALA的II组内含子中，并将形成孔的寡聚受体转化为Acr-Toxin。 ACRS基因位于来自毒素敏感和不敏感柑橘的线粒体基因组。然而，这些转录本在毒素不敏感的柑橘中遭受的处理能力失调，而对毒素敏感的粗糙柠檬中的柑橘类作用则保持完整而没有加工。为了确定在线粒体中是否翻译ACRS，通过蛋白质印迹分析了抗毒素敏感的粗糙柠檬和不敏感柑橘的蛋白质的蛋白质，并用抗acts抗体的蛋白质印迹分析。抗体仅在粗糙的柠檬线粒体上检测到斑点上的肽，而未被测试的任何抗性柑橘柑橘类抗体检测到的肽。这些结果表明，该线粒体ACRS基因的转录后修饰调节毒素植物相互作用中的特异性，其中线粒体中的RNA处理在控制对柑橘酸Acroxoxin的敏感性中起关键作用。