Multiprotein-bridging factor 1 regulates vegetative growth, osmotic stress, and virulence in Magnaporthe oryzae
Multiprotein-bridging factor 1 regulates vegetative growth, osmotic stress, and virulence in Magnaporthe oryzae
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多蛋白桥接因子 1 调节稻瘟病菌的营养生长、渗透压和毒力
DOI：
10.1007/s00294-016-0636-9
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发表时间：
2017-05-01
期刊：
影响因子：
2.5
通讯作者：
Lu, Guo-dong
中科院分区：
文献类型：
--
作者：
Fan, Gaili;Zhang, Kai;Lu, Guo-dong
多蛋白桥接因子1 （MBF1）是一种转录共激活因子，通过桥接序列特异性激活因子样蛋白和TATA-box结合蛋白（TBP）介导转录激活。MBF1已经在拟南芥、酿酒酵母、黑腹果蝇和智人中得到了很好的研究，但在丝状真菌中还不太清楚。在本研究中，我们报道了稻瘟病菌（Magnaporthe oryzae）中MBF1同源物（MoMBF1）的鉴定和表征，该同源物引起毁灭性的稻瘟病，是研究丝状真菌生长发育和致病机制的理想模型。MoMBF1编码一个161个氨基酸的蛋白，具有典型的MBF1结构域和HTH结构域。利用生物信息学方法分析了MoMBF1的结构域及其与不同生物同源物的系统发育关系。我们已经生成了MoMBF1缺失突变体（ΔMoMBF1）和功能互补突变体，发现缺失突变体在营养生长和对外源胁迫（如1 M山梨醇、0.5 M NaCl和5 mM H2O2）的耐受性方面存在显著缺陷。与野生型和互补菌株相比，ΔMoMBF1的致病性较低，感染病灶较小，对植物体内活性氧（ROS）积累的反应也较弱。综上所述，我们的数据表明，MoMBF1是M. oryzae营养生长、致病性和应激反应所必需的。
Multiprotein bridging factor 1 (MBF1) is a transcriptional co-activator that mediates transcriptional activation by bridging sequence-specific activator like proteins and the TATA-box binding protein (TBP). MBF1 has been well-studied in Arabidopsis thaliana, Saccharomyces cerevisiae, Drosophila melanogaster, and Homo sapiens, but it is not well understood in filamentous fungi. In this study, we report the identification and characterization of a MBF1 ortholog (MoMBF1) in the rice blast fungus Magnaporthe oryzae), which causes the devastating rice blast disease and is an ideal model for studying the growth, development and pathogenic mechanisms of filamentous fungi. MoMBF1 encodes a 161 amino acid protein with a typical MBF1 domain and HTH domain. Bioinformatics were used to analyze the structural domains in MoMBF1 and its phylogenetic relationship to other homologs from different organisms. We have generated MoMBF1 deletion mutants (ΔMoMBF1) and functional complementation transformants, and found that the deletion mutants showed significant defects in vegetative growth and tolerance to exogenous stresses, such as 1 M sorbitol, 0.5 M NaCl, and 5 mM H2O2. Moreover, ΔMoMBF1 showed reduced pathogenicity with smaller infection lesions than wild type and the complementation strain, and decreased response to the accumulation of ROS (reactive oxygen species) in planta at the initial infection stage. Taken together, our data indicate that MoMBF1 is required for vegetative growth, pathogenicity and stress response in M. oryzae.