Impact of ROS signalling and ROS scavenging on aging and development of the ascomycete Podospora anserina

• Applicant: Professor Dr. Heinz Dieter Osiewacz
• Subject Area: Plant Cell and Developmental Biology
• Term: from 2011 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 195155890

Reactive oxygen species (ROS) formed during the lifespan of any organism are active in cellular signaling but also cause molecular damage. While the first process is known to be relevant for development, the time-dependent accumulation of ROS-induced damage is considered to be a key for understanding aging. Recently, when studying superoxide dismutases (SODs) in the fungal aging model Podospora anserina, we obtained unexpected results which question this view: (i) deletion strains of the three SOD genes were found to be viable, and (ii) over-expression of the gene coding for the mitochondrial SOD (PaSOD3) was detrimental. The initial characterization of PaSod3 overexpressors revealed an impact of increased PaSOD3 levels on different components of the molecular surveillance system. Now we aim to address the underlying mechanisms to elucidate the impact of ROS signaling vs. ROS damaging on aging and development. First, existing strains with altered SOD level are studied with respect to ROS levels and production, ROS-induced damage and the impact on the expression and abundance of selected components of cellular surveillance pathways. Second, wild-type strains of different age grown under standard conditions or challenged by oxidative stress are analyzed to identify systematic changes during the lifetime of strains. From these investigations we expect to identify new molecular pathways controlling aging and development and interactions between components of them going considerably beyond the state-of-the-art of knowledge about the role of ROS in these fundamental processes.

• DFG Programme: Research Grants