Figure 1.
In the absence of PCSK9, LDL·LDLR is endocytosed into hepatocytes, and then the LDLR is recycled and LDL is digested. In the presence of PCSK9, LDLR is not recycled and the whole complex is decomposed. Thus, PCSK9·LDLR interaction suppresses recycling of LDLR and diminishes uptake of LDL particles by the liver.