CmpacC regulates mycoparasitism, oxalate degradation and antifungal activity in the mycoparasitic fungus Coniothyrium minitans
CmpacC regulates mycoparasitism, oxalate degradation and antifungal activity in the mycoparasitic fungus Coniothyrium minitans
复制标题
DOI：
10.1111/1462-2920.13018
复制
发表时间：
2015-11-01
影响因子：
5.1
通讯作者：
Li, Guoqing
中科院分区：
文献类型：
--
作者：
Lou, Yi;Han, Yongchao;Li, Guoqing
PacC/Rim 101是植物病原真菌的重要致病因子。在这项研究中，我们调查的PacC同源物，CmpacC，在真菌寄生真菌盾壳霉minitans的作用。在酿酒酵母中进行转录激活试验，证实CmpacC具有转录激活活性。破坏CmpacC导致受损的真菌对环境pH值的反应。与野生型相比，CmpacC-破坏突变体CmpacC-29显着抑制几丁质酶和-1，3-葡聚糖酶的活性在pH 5和7，Cmch 1和Cmg 1编码的两种酶分别降低表达水平一致。然而，突变体显示酸性模拟表型，如改善草酸降解和增加的抗真菌活性在pH 6或更高。CmpacC-29在草酸盐降解中的改善功效与编码草酸盐脱羧酶的Cmoxdc 1的增强表达水平一致。Cmch 1和Cmg 1的CmpacC转录激活和Cmoxdc 1的阻遏通过基因启动子区域中PacC/Rim 101共有结合基序的存在和启动子DNA结合测定来验证。提示CmpacC在调节C. minitans mycoparasitism，而在调节草酸降解和可能的抗真菌活性中起抑制作用。迷你坦人
The PacC/Rim101 pH-responsive transcription factor is an important pathogenicity element for many plant-pathogenic fungi. In this study, we investigated the roles of a PacC homologue, CmpacC, in the mycoparasitic fungus Coniothyrium minitans. CmpacC was confirmed to have the transcriptional activation activity by the transcriptional activation test in Saccharomyces cerevisiae. Disruption of CmpacC resulted in impaired fungal responses to ambient pH. Compared to the wild-type, the CmpacC-disruption mutant CmpacC-29 was significantly suppressed for activities of chitinase and -1,3-glucanase at pH 5 and 7, consistent with reduced expression levels of Cmch1 and Cmg1 coding for the two enzymes respectively. However, the mutant displayed acidity-mimicking phenotypes such as improved oxalate degradation and increased antifungal activity at pH 6 or higher. Improved efficacy in oxalate degradation by CmpacC-29 was consistent with the enhanced expression level of Cmoxdc1 coding for oxalate decarboxylase. CmpacC transcriptional activation of Cmch1 and Cmg1 and repression of Cmoxdc1 were verified by the presence of the PacC/Rim101 consensus binding-motifs in gene promoter regions and by the promoter DNA-binding assays. This study suggests that CmpacC plays an activator role in regulation of C. minitans mycoparasitism, whereas plays a repressor role in regulation of oxalate degradation and possibly antifungal activity of C. minitans.