Autophagy is a well-conserved catabolic process, involving the degradation of a cell's own components through the lysosomal/vacuolar machinery. Autophagy is typically induced by nutrient starvation and has a role in nutrient recycling, cellular differentiation, degradation and programmed cell death. Another common response in eukaryotes is the extension of lifespan through dietary restriction (DR). We studied a link between DR and autophagy in the filamentous fungus
Podospora anserina
, a multicellular model organism for ageing studies and mitochondrial deterioration. While both carbon and nitrogen restriction extends lifespan in
P. anserina,
the size of the effect varied with the amount and type of restricted nutrient. Natural genetic variation for the DR response exists. Whereas a switch to carbon restriction up to halfway through the lifetime resulted in extreme lifespan extension for wild-type
P. anserina
, all autophagy-deficient strains had a shorter time window in which ageing could be delayed by DR. Under nitrogen limitation, only Pa
Atg1
and Pa
Atg8
mediate the effect of lifespan extension; the other autophagy-deficient mutants Pa
PspA
and Pa
Uth1
had a similar response as wild-type. Our results thus show that the ageing process impinges on the DR response and that this at least in part involves the genetic regulation of autophagy.
Involvement of PaSNF1 in Fungal Development, Sterigmatocystin Biosynthesis, and Lignocellulosic Degradation in the Filamentous Fungus Podospora anserina
