Palmitoylation of apolipoprotein B is required for proper intracellular sorting and transport of cholesteroyl esters and triglycerides.

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Citation

Zhao Y, McCabe JB, Vance J, Berthiaume LG

Palmitoylation of apolipoprotein B is required for proper intracellular sorting and transport of cholesteroyl esters and triglycerides.

Mol Biol Cell. 2000 Feb;11(2):721-34.

PubMed ID
10679026 [ View in PubMed
]
Abstract

Apolipoprotein B (apoB) is an essential component of chylomicrons, very low density lipoproteins, and low density lipoproteins. ApoB is a palmitoylated protein. To investigate the role of palmitoylation in lipoprotein function, a palmitoylation site was mapped to Cys-1085 and removed by mutagenesis. Secreted lipoprotein particles formed by nonpalmitoylated apoB were smaller and denser and failed to assemble a proper hydrophobic core. Indeed, the relative concentrations of nonpolar lipids were three to four times lower in lipoprotein particles containing mutant apoB compared with those containing wild-type apoB, whereas levels of polar lipids isolated from wild-type or mutant apoB lipoprotein particles appeared identical. Palmitoylation localized apoB to large vesicular structures corresponding to a subcompartment of the endoplasmic reticulum, where addition of neutral lipids was postulated to occur. In contrast, nonpalmitoylated apoB was concentrated in a dense perinuclear area corresponding to the Golgi compartment. The involvement of palmitoylation as a structural requirement for proper assembly of the hydrophobic core of the lipoprotein particle and its intracellular sorting represent novel roles for this posttranslational modification.

DrugBank Data that Cites this Article

Polypeptides
NameUniProt ID
Apolipoprotein B-100P04114Details