Histone acetylation, balanced by histone acetyltransferase (HAT) and histone deacetylase (HDAC) complexes, affects dynamic transitions of chromatin structure to regulate transcriptional accessibility. However, little is known about the interplay between HAT and HDAC complexes in Fusarium graminearum, a causal agent of Fusarium Head Blight (FHB) that uniquely contains chromosomal regions enriched for house-keeping or infection-related genes. In this study, we identified the ortholog of the human inhibitor of growth (ING1) gene in F. graminearum (FNG1) and found that it specifically interacts with the FgEsa1 HAT of the NuA4 complex. Deletion of FNG1 led to severe growth defects and blocked conidiation, sexual reproduction, DON production, and plant infection. The fng1 mutant was normal in H3 acetylation but significantly reduced in H4 acetylation. A total of 34 spontaneous suppressors of fng1 with faster growth rate were isolated. Most of them were still defective in sexual reproduction and plant infection. Thirty two of them had mutations in orthologs of yeast RPD3, SIN3, and SDS3, three key components of the yeast Rpd3L HDAC complex. Four mutations in these three genes were verified to suppress the defects of fng1 mutant in growth and H4 acetylation. The rest two suppressor strains had a frameshift or nonsense mutation in a glutamine-rich hypothetical protein that may be a novel component of the FgRpd3 HDAC complex in filamentous fungi. FgRpd3, like Fng1, localized in euchromatin. Deletion of FgRPD3 resulted in severe growth defects and elevated H4 acetylation. In contract, the Fgsds3 deletion mutant had only a minor reduction in growth rate but FgSIN3 appeared to be an essential gene. RNA-seq analysis revealed that 48.1% and 54.2% of the genes with altered expression levels in the fng1 mutant were recovered to normal expression levels in two suppressor strains with mutations in FgRPD3 and FgSDS3, respectively. Taken together, our data showed that Fng1 is important for H4 acetylation as a component of the NuA4 complex and functionally related to the FgRpd3 HDAC complex for transcriptional regulation of genes important for growth, conidiation, sexual reproduction, and plant infection in F. graminearum.

组蛋白乙酰化受组蛋白乙酰转移酶（HAT）和组蛋白脱乙酰酶（HDAC）复合物的平衡，影响染色质结构的动态转变以调节转录可及性。然而，关于镰刀镰刀菌（Fusarium Head Blight，FHB）的病原体，镰刀镰刀菌（Fusarium graminearum）中的HAT和HDAC复合物之间的相互作用鲜为人知。在这项研究中，我们发现在增长（ING1）基因的人类抑制剂的同源基因˚F。graminearum（FNG1），发现它与NuA4复合体的FgEsa1 HAT特异性相互作用。删除FNG1导致严重的生长缺陷和受精卵，有性繁殖，呕吐毒素的产生和植物感染。所述fng1突变体在H3乙酰化正常的，但在H4乙酰显著降低。总共分离出34个具有更快生长速率的fng1自发抑制因子。他们中的大多数仍在有性生殖和植物感染方面存在缺陷。其中的三十二个在酵母RPD3，SIN3和SDS3的直系同源物中发生了突变，这是酵母Rpd3L HDAC复合体的三个关键组成部分。这三个基因中的四个突变被证实可以抑制fng1的缺陷生长和H4乙酰化的突变体。其余两个抑制菌株在富含谷氨酰胺的假设蛋白中具有移码或无义突变，这可能是丝状真菌中FgRpd3 HDAC复合物的新成分。FgRpd3与Fng1一样，位于常染色质中。FgRPD3的删除导致严重的生长缺陷和高水平的H4乙酰化。合同中，Fgsds3缺失突变体的生长速率仅略有降低，但FgSIN3似乎是必需的基因。RNA-seq分析显示，在两个FgRPD3和FgSDS3突变的抑制菌株中，fng1突变体中表达水平改变的基因的48.1％和54.2％被恢复到正常表达水平， 分别。总之，我们的数据显示，Fng1是作为一个组件，用于H4乙酰化重要NuA4复杂和功能相关的FgRpd3 HDAC复杂的基因生长，产孢，有性繁殖和植物感染的重要的转录调控˚F。菌。