A Common Binding Site on the Microsomal Triglyceride Transfer Protein for Apolipoprotein B and Protein Disulfide Isomerase

Microsomal triglyceride transfer protein: a multifunctional protein.

Microsomal triglyceride transfer protein (MTP) is a heterodimeric protein that transfers neutral lipids between membranes in vitro. Absence of this lipid transfer activity in the microsomes of abetalipoproteinemia patients established its pivotal function in lipoprotein assembly. Recent studies indicate that the lipid transfer activity is involved in importing triglycerides into the lumen of th...

A deficiency of microsomal triglyceride transfer protein reduces apolipoprotein B secretion.

Microsomal triglyceride transfer protein (MTP) transfers lipids to apolipoprotein B (apoB) within the endoplasmic reticulum, a process that involves direct interactions between apoB and the large subunit of MTP. Recent studies with heterozygous MTP knockout mice have suggested that half-normal levels of MTP in the liver reduce apoB secretion. We hypothesized that reduced apoB secretion in the s...

Microsomal Triglyceride Transfer Protein and its Role in Apolipoprotein B- Lipoprotein Assembly

Apolipoprotein B-containing Lipoprotein Assembly in Microsomal Triglyceride Transfer Protein Deficient McA-RH7777 Cell Line

Apolipoprotein B-containing lipoprotein assembly in microsomal triglyceride transfer protein-deficient McA-RH7777 cells.

Microsomal triglyceride transfer protein (MTP) is required for the assembly and secretion of apolipoprotein (apo) B-containing lipoproteins. Previously, we demonstrated that the N-terminal 1,000 residues of apoB (apoB:1000) are necessary for the initiation of apoB-containing lipoprotein assembly in rat hepatoma McA-RH7777 cells and that these particles are phospholipid (PL) rich. To determine i...