Transcriptional profiling for Aspergillus nidulans HogA MAPK signaling pathway in response to fludioxonil and osmotic stress
Transcriptional profiling for Aspergillus nidulans HogA MAPK signaling pathway in response to fludioxonil and osmotic stress
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DOI：
10.1016/j.fgb.2009.07.003
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发表时间：
2009-11-01
影响因子：
3
通讯作者：
Abe, Keietsu
中科院分区：
文献类型：
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作者：
Hagiwara, Daisuke;Asano, Yoshihiro;Abe, Keietsu
在丝状真菌中，His-Asp磷酸化信号传导系统和HOG途径参与杀真菌剂咯菌腈和异菌脲的作用，以及渗透和氧化应激反应。构巢曲霉反应调节因子（RR）SskA和SrrA以及组氨酸激酶（HK）NikA参与这些杀真菌剂的生长抑制作用。为了进一步了解这些信号系统的分子基础，我们进行了咯菌腈和A. nidulans。一个全球性的表达分析表明，大量的基因被调制咯菌腈处理在一个SskA依赖的方式，而SrrA几乎没有贡献这种调制。咯菌腈上调或下调的基因（分别为FUG或FDG）也依赖于HogA MAPK级联。我们发现SskA-HogA途径调节atfA基因的表达，该基因编码一种参与分生孢子胁迫耐受性的转录因子。从微阵列分析的结果，AtfA依赖的FUG很大程度上重叠与HogA依赖的FUG，表明AtfA的功能下游的HogA MAPK。一系列的微阵列分析表明，推断的SskA-HogA-AtfA途径涉及的转录响应渗透胁迫以及咯菌腈。srrA atfA null双突变体关闭了SrrA和SskA-HogA-AtfA途径，并表现出对渗透胁迫的敏感性，但对咯菌腈没有抗性。我们的数据显示，咯菌腈的生长抑制作用取决于AtfA以外的因素，尽管事实上AtfA的HogA MAPK级联下游的功能。随后HogA MAPK级联反应的His-Asp磷酸化系统中的应激反应的复杂性进行了讨论。(C)2009 Elsevier Inc. All rights reserved.
In filamentous fungi, the His-Asp phosphorelay signaling system and HOG pathway are involved in the action of the fungicides, fludioxonil, and iprodione, as well as osmotic and oxidative stress responses. Aspergillus nidulans response regulators (RRs), SskA and SrrA, and histidine kinase (HK), NikA, are involved in the growth inhibitory effects of these fungicides. To gain further insights into the molecular basis for these signaling systems, we performed DNA microarray analyses of fludioxonil and osmotic stress responses in A. nidulans. A global expression analysis revealed that a large number of genes were modulated by fludioxonil treatment in an SskA-dependent manner, whereas SrrA hardly contributed to this modulation. The fludioxonil up-regulated or down-regulated genes (FUGs or FDGs, respectively) are also dependent on the HogA MAPK cascade. We found that the SskA-HogA pathway regulates expression of atfA gene encoding a transcription factor involved in conidia stress tolerance. From the results of microarray analyses, AtfA-dependent FUGs largely overlapped with HogA-dependent FUGs, suggesting that AtfA functions downstream of the HogA MAPK. A series of microarray analyses showed that the inferred SskA-HogA-AtfA pathway is implicated in the transcriptional response to osmotic stress as well as fludioxonil. The srrA atfA null double mutant turns off the SrrA and SskA-HogA-AtfA pathways and showed sensitivity to osmotic stress but no resistance to fludioxonil. Our data revealed that the growth inhibitory effect of fludioxonil depends on factors other than AtfA in spite of the fact that AtfA functions downstream of the HogA MAPK cascade. The complexity of the stress response in the His-Asp phosphorelay system followed by the HogA MAPK cascade is discussed. (C) 2009 Elsevier Inc. All rights reserved.