The role of fungal NADPH oxidase complexes in differentiation and virulence

NADPH氧化酶(NOx)产生的活性氧种(ROS)在动植物的病原菌防御反应和多种分化过程中发挥着重要作用。越来越多的证据表明，在真菌中，这些膜复合体也参与了所有主要的发育过程：它们对极地生长、性别分化和毒力有影响。然而，对于复杂的组成、招募和定位，以及它们对许多重要细胞过程的影响的分子机制，仍然缺乏相当大的了解。在第一个项目期对两种生活方式完全不同、NOx功能明显不同的真菌--生物营养麦角菌Clavicep Purpurea和坏死性灰霉菌Botrytis cinerea--的NOx复合体和ROS信号成分进行了广泛的分析基础上，我们将在第二阶段重点研究模式系统B.cinerea中NOx复合体的详细功能特征。我们将研究NOx复合体的特定组成/招募，定位，与特定的发育阶段/代谢活动有关，重点是内质网中可能的功能。我们将在分化过程(例如穿透结构)的背景下研究NOx对细胞骨架的影响，并分析影响哺乳动物系统中NOx活性的调节电路，例如脂质信号。此外，我们将基于现有的ROS高产突变体，尝试寻找替代的ROS来源。

Reactive oxygen species (ROS) generated by NADPH oxidases (Nox) play an important role in pathogen defense reactions and a broad variety of differentiation processes in animals and plants. There is growing evidence that also in fungi these membrane complexes are involved in all major developmental processes: they have impact on polar growth, sexual differentiation and virulence. Still there is considerable lack of knowledge on complex composition, recruitment and localization, and on the molecular mechanisms underlying their impact on so many important cellular processes. Based on the broad analysis in the first project period of the Nox complexes and ROS signaling components in general in two fungi with completely different lifestyle and obviously significantly different Nox functions - the biotrophic ergot fungus Claviceps purpurea and the necrotrophic grey mold fungus Botrytis cinerea-, we will focus in this second period on a detailed functional characterization of the Nox complexes in the model system B.cinerea. We will investigate the specific composition/recruitment of the Nox complexes, the localization, linked to specific developmental stages/metabolic activities, focusing on a possible function in the ER. We will study the impact of Nox on the cytoskeleton, in the context of differentiation processes (e.g.penetration structures) and analyse regulatory circuits which affect Nox activity in mammalian systems, e.g. lipid signaling. In addition, we will try to identify alternative ROS sources, based on existing ROS overproducing mutants.