Microsomal Triglyceride Transfer Protein (MTTP)

Microsomal triglyceride transfer protein, also known as MTTP or MTP, is the large subunit of the heterodimeric microsomal triaglyceride transfer protein. Protein disulfide isomerase (PDI) completes the heterodimeric microsomal triaglyceride transfer protein, which has been shown to play a central role in lipoprotein assembly. Mutations in MTP can cause abetalipoproteinemia.

Defects in MTTP are the cause of abetalipoproteinemia (ABL). ABL is an autosomal recessive disorder of lipoprotein metabolism. Affected individuals produce virtually no circulating apolipoprotein B-containing lipoproteins.Malabsorption of the antioxidant vitamin E occurs, leading to spinocerebellar and retinal degeneration.