Functional analysis of C2H2 zinc finger transcription factor CrzA involved in calcium signaling in Aspergillus nidulans
Functional analysis of C2H2 zinc finger transcription factor CrzA involved in calcium signaling in Aspergillus nidulans
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DOI：
10.1007/s00294-008-0220-z
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发表时间：
2008-12-01
期刊：
影响因子：
2.5
通讯作者：
Abe, Keietsu
中科院分区：
文献类型：
--
作者：
Hagiwara, Daisuke;Kondo, Atsushi;Abe, Keietsu
钙信号系统广泛应用于真核生物中，参与多种生物过程的调控。钙调神经磷酸酶是一种重要的信号传导成分，在多种真菌中介导离子稳态和毒力。基于对芽殖酵母进行的深入研究，转录因子Crz 1 p被认为是钙调神经磷酸酶的靶点。为了深入了解钙信号，Crz 1 p同源物（CrzA）在丝状真菌构巢曲霉被确定和其功能，特别是参考钙反应的特点。crzA基因缺失突变体对高浓度的Mn ~（2+）和Ca ~（2+）敏感，并介导了P型钙ATP酶同源基因的表达。与DNA微阵列的综合转录分析表明，CrzA调节液泡Ca 2 +/H+交换基因的表达，响应外部钙刺激。提示钙调神经磷酸酶-CrzA途径是A. nidulans。此外，crzA/hogA双突变体表现出对渗透胁迫的敏感性，表明钙稳态对于适应渗透胁迫的重要性，渗透胁迫是丝状真菌中的普遍胁迫。
Calcium signaling systems are widely employed in eukaryotes and are implicated in the regulation of diverse biological processes. Calcineurin is an important signaling component, which mediates ion homeostasis and virulence in several fungi. Based on intensive studies conducted on budding yeast, transcription factor Crz1p is thought to be a target of calcineurin. To provide insight into calcium signaling, a Crz1p homolog (CrzA) in a filamentous fungus Aspergillus nidulans was identified and its function with special reference to calcium response was characterized. A crzA gene disruption mutant exhibited sensitivity to high concentrations of Mn2+ and Ca2+, and mediated the expression of P-type calcium-ATPase homologous genes. Comprehensive transcriptional analysis with DNA microarrays indicated that CrzA regulates the expression of a vacuolar Ca2+/H+ exchanger gene in response to external calcium stimuli. It is suggested that the calcineurin-CrzA pathway is the mediator of Ca2+ homeostasis in A. nidulans. Moreover, a crzA/hogA double mutant showed hypersensitivity to osmotic stress, indicating the importance of calcium homeostasis for adaptation to osmotic stress, a universal stress in filamentous fungi.