作为爆炸病的病原体,稻瘟病菌是水稻最具破坏性的病原真菌之一。组蛋白乙酰化/脱乙酰化对于染色质超结构的重塑和因此改变基因表达是重要的。在这项研究中,两个编码组蛋白脱乙酰酶的基因,即,在米曲霉中鉴定并功能表征MoRPD3和MoHST4。适当的菌丝体生长和致病性需要MoHst4,而MoRpd3的过量生产导致致病性丧失,可能是由于分生孢子细胞死亡的阻断和寄主植物内的入侵生长受限。绿色荧光蛋白(GFP)-MoRpd3定位于营养菌丝和分生孢子中的细胞核和细胞质。通过比较转录组学分析,我们确定了潜在的靶基因,由含有MoRpd3或MoHst4的组蛋白脱乙酰酶(HDACs)表观遗传调控,这可能有助于分生孢子形成和/或分生孢子细胞死亡,这是成功的附着体介导的宿主入侵的先决条件。一起来看,我们的结果表明,组蛋白脱乙酰酶MoRpd3和MoHst4差异调节菌丝体生长,无性发育,米曲霉的发病机制。重要性HDAC(组蛋白脱乙酰酶)调节生长的各个方面,发展,和植物病原真菌的致病机理。HDACI至III类的大多数成员都具有功能特征,除直系同源Rpd3和Hst4外,稻瘟病真菌稻瘟病菌。在这项研究中,我们通过反向遗传学评估了MoRpd3和MoHst4的功能,发现它们差异调节米曲霉营养生长,无性发育,和感染。特别是,MoRpd3负调节米曲霉致病性,可能是通过抑制分生孢子细胞死亡,我们最近报道说,这对附睾成熟和功能至关重要。总的来说,这项研究扩大了我们对真菌病理生物学及其在细胞死亡和植物分化过程中组蛋白修饰的关键调控的理解。
As the causal agent of the blast disease, Magnaporthe oryzae is one of the most destructive fungal pathogens of rice. Histone acetylation/deacetylation is important for remodeling of chromatin superstructure and thus altering gene expression. In this study, two genes encoding histone deacetylases, namely, MoRPD3 and MoHST4, were identified and functionally characterized in M. oryzae. MoHst4 was required for proper mycelial growth and pathogenicity, whereas overproduction of MoRpd3 led to loss of pathogenicity, likely due to a block in conidial cell death and restricted invasive growth within the host plants. Green fluorescent protein (GFP)-MoRpd3 localized to the nucleus and cytoplasm in vegetative hyphae and developing conidia. By comparative transcriptomics analysis, we identified potential target genes epigenetically regulated by histone deacetylases (HDACs) containing MoRpd3 or MoHst4, which may contribute to conidia formation and/or conidial cell death, which is a prerequisite for successful appressorium-mediated host invasion. Taken together, our results suggest that histone deacetylases MoRpd3 and MoHst4 differentially regulate mycelial growth, asexual development, and pathogenesis in M. oryzae. IMPORTANCE HDACs (histone deacetylases) regulate various aspects of growth, development, and pathogenesis in plant-pathogenic fungi. Most members of HDAC classes I to III have been functionally characterized, except for orthologous
Rpd3 and Hst4, in the rice blast fungus Magnaporthe oryzae. In this study, we assessed the function of MoRpd3 and MoHst4 by reverse genetics and found that they differentially regulate M. oryzae vegetative growth, asexual development, and infection. Particularly, MoRpd3 negatively regulates M. oryzae pathogenicity, likely through suppression of conidial cell death, which we recently reported as being critical for appressorium maturation and functioning. Overall, this study broadens our understanding of fungal pathobiology and its critical regulation by histone modification(s) during cell death and in planta differentiation.