Rossi M, Goggin F L, Milligan S B, Kaloshian I, Ullman D E, Williamson V M
Department of Nematology, University of California, Davis, CA 95616, USA.
Proc Natl Acad Sci U S A. 1998 Aug 18;95(17):9750-4. doi: 10.1073/pnas.95.17.9750.
Resistance against the aphid Macrosiphum euphorbiae previously was observed in tomato and attributed to a novel gene, designated Meu-1, tightly linked to the nematode resistance gene, Mi. Recent cloning of Mi allowed us to determine whether Meu-1 and Mi are the same gene. We show that Mi is expressed in leaves, that aphid resistance is isolate-specific, and that susceptible tomato transformed with Mi is resistant to the same aphid isolates as the original resistant lines. We conclude that Mi and Meu-1 are the same gene and that Mi mediates resistance against both aphids and nematodes, organisms belonging to different phyla. Mi is the first example of a plant resistance gene active against two such distantly related organisms. Furthermore, it is the first isolate-specific insect resistance gene to be cloned and belongs to the nucleotide-binding, leucine-rich repeat family of resistance genes.
先前在番茄中观察到对蚜虫大戟长管蚜的抗性，并归因于一个与线虫抗性基因Mi紧密连锁的新基因，命名为Meu-1。最近Mi的克隆使我们能够确定Meu-1和Mi是否为同一基因。我们发现Mi在叶片中表达，蚜虫抗性具有分离物特异性，用Mi转化的感病番茄对与原始抗性品系相同的蚜虫分离物具有抗性。我们得出结论，Mi和Meu-1是同一基因，且Mi介导对蚜虫和线虫（属于不同门的生物）的抗性。Mi是对两种如此远缘相关生物具有活性的植物抗性基因的首个例子。此外，它是首个被克隆的分离物特异性昆虫抗性基因，属于核苷酸结合、富含亮氨酸重复序列的抗性基因家族。
