Macroautophagy (hereafter referred to simply as autophagy) is a catabolic 
pathway that mediates the degradation of long-lived proteins and organelles in 
eukaryotic cells. The regulation of mitochondrial degradation through autophagy 
plays an essential role in the maintenance and quality control of this 
organelle. Compared with our understanding of the essential function of 
mitochondria in many aspects of cellular metabolism such as energy production 
and of the role of dysfunctional mitochondria in cell death, little is known 
regarding their degradation and especially how upstream signaling pathways 
control this process. Here, we report that two mitogen-activated protein kinases 
(MAPKs), Slt2 and Hog1, are required for mitophagy in Saccharomyces cerevisiae. 
Slt2 is required for the degradation of both mitochondria and peroxisomes (via 
pexophagy), whereas Hog1 functions specifically in mitophagy. Slt2 also affects 
the recruitment of mitochondria to the phagophore assembly site (PAS), a 
critical step in the packaging of cargo for selective degradation.