Iwate Biotechnology Research Center, Iwate, Japan.
FEMS Microbiol Lett. 2014 Mar;352(1):104-13. doi: 10.1111/1574-6968.12369. Epub 2014 Jan 13.
In a large-scale gene disruption screen of Magnaporthe oryzae, a gene MoST1 encoding a protein belonging to the hexose transporter family was identified as a gene required for conidiation and culture pigmentation. The gene MoST1 located on chromosome V of the M. oryzae genome was predicted to be 1892 bp in length with two introns encoding a 547-amino-acid protein with 12 putative transmembrane domains. Targeted gene disruption of MoST1 resulted in a mutant (most1) with extremely poor conidiation and defects in colony melanization. These phenotypes were complemented by re-introduction of an intact copy of MoST1. We generated a transgenic line harboring a vector containing the MoST1 promoter fused with a reporter protein gene mCherry. The mCherry fluorescence was observed in mycelia, conidia, germ tubes, and appressoria in M. oryzae. There are 66 other hexose transporter-like genes in M. oryzae, and we performed complementation assay with three genes most closely related to MoST1. However, none of them complemented the most1 mutant in conidiation and melanization, indicating that the homologs do not complement the function of MoST1. These results suggest that MoST1 has a specific role for conidiation and mycelial melanization, which is not shared by other hexose transporter family of M. oryzae.
在大规模的稻瘟病菌基因敲除筛选中，鉴定到一个编码属于己糖转运蛋白家族的蛋白的基因 MoST1 是产孢和培养色素形成所必需的。MoST1 基因位于稻瘟病菌基因组的 V 号染色体上，预测长度为 1892bp，包含两个内含子，编码一个 547 个氨基酸的蛋白，具有 12 个推定的跨膜结构域。MoST1 基因的靶向敲除导致突变体（most1）产孢能力极差，菌落黑化缺陷。这些表型可以通过重新引入完整的 MoST1 拷贝得到互补。我们生成了一个携带含有 MoST1 启动子与报告蛋白基因 mCherry 融合的载体的转基因系。在稻瘟病菌的菌丝、分生孢子、芽管和附着胞中观察到 mCherry 荧光。在稻瘟病菌中有 66 个其他的己糖转运蛋白样基因，我们用与 MoST1 最密切相关的三个基因进行了互补测定。然而，它们都没有互补 most1 突变体在产孢和黑化方面的缺陷，表明这些同源物不能互补 MoST1 的功能。这些结果表明，MoST1 在产孢和菌丝黑化方面具有特定的作用，而不是与稻瘟病菌其他己糖转运蛋白家族共享的。
