FgVELB is associated with vegetative differentiation, secondary metabolism and virulence in Fusarium graminearum
FgVELB is associated with vegetative differentiation, secondary metabolism and virulence in Fusarium graminearum
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FgVELB 与禾谷镰刀菌的营养分化、次生代谢和毒力相关
DOI：
10.1016/j.fgb.2012.06.005
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发表时间：
2012-08-01
影响因子：
3
通讯作者：
Ma, Zhonghua
中科院分区：
文献类型：
--
作者：
Jiang, Jinhua;Yun, Yingzi;Ma, Zhonghua
含有VeA、VelB和LaeA的天鹅绒复合物在曲霉菌的次生代谢和多种细胞过程的调节中起着重要作用。在这项研究中，我们确定FgVelB，构巢曲霉VelB的同源物，从禾谷镰刀菌使用BLASTP程序。FgVELB基因的破坏导致了几种表型缺陷，包括气生菌丝形成的抑制，菌丝疏水性降低和分生孢子的高度增加。该突变体表现出增加的抗渗透胁迫和细胞壁损伤剂，这可能与高水平的甘油积累的突变体。此外，突变体表现出增加的敏感性苯基吡咯杀菌剂咯菌腈。超微结构和组织化学分析表明，FgVELB缺失突变体的分生孢子含有大量的脂滴。致病性试验表明，FgVELB缺失突变体对开花小麦的致病力降低，这与FgVelB参与F.禾谷早熟禾所有的缺陷都通过突变体与野生型FgVELB基因的遗传互补而恢复。酵母双杂交试验表明FgVelB不与FgVeA相互作用。综上所述，本研究的结果表明FgVelB在F.禾谷早熟禾(C)2012 Elsevier Inc. All rights reserved.
The velvet complex containing VeA, VelB and LaeA has been showed to play critical roles in the regulation of secondary metabolism and diverse cellular processes in Aspergillus spp. In this study, we identified FgVelB, a homolog of Aspergillus nidulans VelB, from Fusarium graminearum using the BLASTP program. Disruption of FgVELB gene led to several phenotypic defects, including suppression of aerial hyphae formation, reduced hyphal hydrophobicity and highly increased conidiation. The mutant showed increased resistance to osmotic stress and cell wall-damaging agents, which may be related to a high level of glycerol accumulation in the mutant. Additionally, the mutant exhibited increased sensitivity to the phenylpyrrole fungicide fludioxonil. Ultrastructural and histochemical analyses revealed that conidia of FgVELB deletion mutant contained numerous lipid droplets. Pathogenicity assays showed FgVELB deletion mutant was impaired in virulence on flowering wheat head, which is consistent with the observation that FgVelB is involved in the regulation of deoxynivalenol biosynthesis in F. graminearum. All of the defects were restored by genetic complementation of the mutant with wild-type FgVELB gene. Yeast two hybrid assays showed that FgVelB does not interact with FgVeA. Taken together, results of this study indicated that FgVelB plays a critical role in the regulation of various cellular processes in F. graminearum. (C) 2012 Elsevier Inc. All rights reserved.