Figure 6.

cAMP-PRKA signaling antagonizes mitophagy. Mitochondrial sADCYs are responsible for the biosynthesis of cAMP, which supports the PRKA activity. cAMP-PRKA phosphorylates CREB1 and activates the transcription of major mitochondrial biogenesis-associated factors. Mitochondrial fission protein DNM1L could be phosphorylated by PRKA, and this phosphorylation prevents its translocation onto the mitochondrial surface for mitochondrial fission. Furthermore, PRKA also phosphorylates IMMT, CHCHD3, PRKN and BNIP3L, abrogating PRKN- and BNIP3L-mediated mitophagy. MAP1LC3 phosphorylation by PRKA represses its translocation onto phagophores, thus inhibits general autophagy.