Rapamycin mimics the incompatibility reaction in the fungus Podospora anserina
Rapamycin mimics the incompatibility reaction in the fungus Podospora anserina
复制标题
DOI：
10.1128/ec.2.2.238-246.2003
复制
发表时间：
2003-04-01
期刊：
影响因子：
--
通讯作者：
Clavé, C
中科院分区：
文献类型：
--
作者：
Dementhon, K;Paoletti, M;Clavé, C
在丝状真菌中，当不同基因型的细胞融合时，发生程序性细胞死亡（PCD）反应。这种反应是由称为het基因座（异核体不相容性）的特定基因座的遗传差异引起的。虽然几个het基因的特点，这种细胞死亡反应的机制和PCD在高等真核生物中的关系仍然在很大程度上是未知的。在鹅柄孢霉中，已经鉴定了在由het-R het-V相互作用触发的细胞死亡反应期间诱导的基因，并将其称为idi基因。在此，我们描述了一个idi基因（idi-1）的功能特征，并探讨了不相容性和营养饥饿反应之间的联系。我们发现IDI-1是一种细胞壁蛋白，在正常生长过程中定位于隔膜。我们发现，诱导idi-1和其他已知的idi基因是不特定的不相容性反应。idi基因在氮和碳饥饿时被雷帕霉素诱导，雷帕霉素是TOR激酶途径的特异性抑制剂。在雷帕霉素处理期间还观察到het-R het-V不相容性的细胞学标志（增加的分隔、空泡化、脂滴聚结、诱导自噬和细胞死亡）。在全球范围内的细胞学变化和基因表达的修饰过程中发生的不相容性反应是类似的饥饿或雷帕霉素治疗期间观察到的。
In filamentous fungi, a programmed cell death (PCD) reaction occurs when cells of unlike genotype fuse. This reaction is caused by genetic differences at specific loci termed het loci (for heterokaryon incompatibility). Although several het genes have been characterized, the mechanism of this cell death reaction and its relation to PCD in higher eukaryotes remains largely unknown. In Podospora anserina, genes induced during the cell death reaction triggered by the het-R het-V interaction have been identified and termed idi genes. Herein, we describe the functional characterization of one idi gene (idi-1) and explore the connection between incompatibility and the response to nutrient starvation. We show that IDI-1 is a cell wall protein which localizes at the septum during normal growth. We found that induction of idi-1 and of the other known idi genes is not specific of the incompatibility reaction. The idi genes are induced upon nitrogen and carbon starvation and by rapamycin, a specific inhibitor of the TOR kinase pathway. The cytological hallmarks of het-R het-V incompatibility (increased septation, vacuolization, coalescence of lipid droplets, induction of autophagy, and cell death) are also observed during rapamycin treatment. Globally the cytological alterations and modifications in gene expression occurring during the incompatibility reaction are similar to those observed during starvation or rapamycin treatment.