Figure 8.

Model graph proposing the changes of lysosomes and mitochondria brought by the absence of SCARB2. The normal activation of mTORC1 was disrupted at the surface of swollen lysosome as a consequence of Scarb2 deficiency, leading to changes in the mTORC1 pathway with decreased phosphorylation of mTORC1 and 4E-BPs. Thus, the expression of Tfam was down-regulated and the ability to produce ATP by mitochondrial oxidative phosphorylation was reduced. The impaired OXPHOS and increased glycolysis leads to the waste of energy, resulting in less lipid accumulation and less fat mass in Scarb2^−/− mice.