MAGGY, a retrotransposon in the genome of the rice blast fungus Magnaporthe grisea
MAGGY, a retrotransposon in the genome of the rice blast fungus Magnaporthe grisea
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DOI：
10.1007/bf02174115
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发表时间：
1996-07-26
期刊：
影响因子：
--
通讯作者：
Leong, SA
中科院分区：
文献类型：
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作者：
Farman, ML;Tosa, Y;Leong, SA
从稻瘟病菌2539菌株的基因组中分离出了先前描述的重复DNA序列（CH 2 -8）的全长拷贝。对完整元件的一个拷贝进行测序，发现其类似于吉普赛样LTR反转录转座子。我们将这种元素命名为MAGGY（MAGnaporthe Gypsy-like element）。MARGY包含两个内部ORF，推定编码Gag、Pol和Env样蛋白，这些蛋白与其他丝状真菌中鉴定的逆转录元件编码的肽相似。MAGGY在M.稻瘟病菌从地理上分散的地点和不同的宿主分离。它是目前在所有9个水稻致病菌株的基因组中的高拷贝数检查。相比之下，M.发现从其它禾本科分离的稻瘟病菌株具有不同拷贝数的MAGGY，在某些情况下该元件完全不存在。MAGGY的广泛分布表明该元件已侵入M.稻瘟病菌在稻特异性形式进化之前就已经存在。此后，它可能已横向传播到其他次特定群体。与我们测序的元件相对应的一个MAGGY拷贝位于地理上分散的菌株基因组中的相同位置，这表明该元件的拷贝是一个相对古老的插入。
Full-length copies of a previously described repetitive DNA sequence (CH2-8) were isolated from the genome of the Magnaporthe grisea strain 2539, One copy of the complete element was sequenced and found to resemble a gypsy-like LTR retrotransposon. We named this element MAGGY (MAGnaporthe GYpsy-like element). MAGGY contains two internal ORFs putatively encoding Gag, Pol and Env-like proteins which are similar to peptides encoded by retroelements identified in other filamentous fungi. MAGGY was found to be widely distributed among M. grisea isolates from geographically dispersed locations and different hosts. It was present in high copy number in the genomes of all nine rice-pathogenic isolates examined. By contrast, M. grisea strains isolated from other Gramineae were found to possess varying copy numbers of MAGGY and in some cases the element was completely absent. The wide distribution of MAGGY suggests that this element invaded the genome of M. grisea prior to the evolution of rice-specific form(s). It may since have been horizontally transmitted to other sub-specific groups. One copy of MAGGY, corresponding to the element we sequenced, was located at identical locations in the genomes of geographically dispersed strains, suggesting that this copy of the element is a relatively ancient insertion.