Non-specific lipid-transfer protein also known as sterol carrier protein 2 (SCP-2) or propanoyl-CoA C-acyltransferase is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the SCP2 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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Function

This gene encodes two proteins: sterol carrier protein X (SCPx) and sterol carrier protein 2 (SCP2), as a result of transcription initiation from 2 independently regulated promoters. The transcript initiated from the proximal promoter encodes the longer SCPx protein, and the transcript initiated from the distal promoter encodes the shorter SCP2 protein, with the 2 proteins sharing a common C-terminus. Evidence suggests that the SCPx protein is a peroxisome

Peroxisome

Peroxisomes are organelles found in virtually all eukaryotic cells. They are involved in the catabolism of very long chain fatty acids, branched chain fatty acids, D-amino acids, polyamines, and biosynthesis of plasmalogens, etherphospholipids critical for the normal function of mammalian brains...

-associated thiolase

Thiolase

Thiolases also known as acetyl-Coenzyme A acetyltransferases are enzymes which converts two units of acetyl-CoA to acetoacetyl CoA in the mevalonate pathway....

 that is involved in the oxidation of branched chain fatty acids, while the SCP2 protein is thought to be an intracellular lipid transfer protein. Alternative splicing of this gene produces multiple transcript variants, some encoding different isoforms. The full-length nature of all transcript variants has not been determined.

Clinical significance

This gene is highly expressed in organs involved in lipid metabolism, and may play a role in Zellweger syndrome

Zellweger syndrome

Zellweger syndrome, also called cerebrohepatorenal syndrome is a rare, congenital disorder, characterized by the reduction or absence of functional peroxisomes in the cells of an individual. It is one of a family of disorders called leukodystrophies...

, in which cells are deficient in peroxisomes and have impaired bile acid

Bile acid

Bile acids are steroid acids found predominantly in the bile of mammals. Bile salts are bile acids compounded with a cation, usually sodium. In humans, the salts of taurocholic acid and glycocholic acid represent approximately eighty percent of all bile salts. The two major bile acids are cholic...

 synthesis.

Interactions

SCP2 has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with Caveolin 1 and peroxisomal receptor PEX5

PEX5

Peroxisomal targeting signal 1 receptor is a protein that in humans is encoded by the PEX5 gene.-Interactions:PEX5 has been shown to interact with PEX12, PEX13 and PEX14.-External Links:* *...

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