High Density Lipoprotein: Assembly, Structure, Cargo, and Functions

Figure 2

ABCA1 cholesterol efflux and stabilising/destabilising modifications. JAK-2 (red) is activated upon apoA-I binding, resulting in autophosphorylation of JAK-2, stabilisation of ABCA1, increased apoA-I binding, and cholesterol efflux. Phosphorylation of the tyrosine residues in the PEST motif (indicated by the black triangles) results in ABCA1 degradation. Protein Kinase A phosphorylates serines (indicated by the red diamonds) required for lipid transport. Protein Kinase CK2 (indicated by the black circles) phosphorylates ABCA1 and down-regulates the transporters activity.