Figure 5.

Model for mtDNA copy number regulation by POLG in dependence of autophagy. POLG regulates mtDNA copy number by balanced DNA synthesis and degradation. During starvation, autophagy provides metabolites to fuel nucleotide pools (dNTPs) and prevent elevated ROS production in mitochondria, which is required for sustained mtDNA synthesis and suppressed mtDNA degradation by POLG.