Primary Information |
|---|
| BoMiProt ID | Bomi3971 |
|---|
| Protein Name | Apolipoprotein C-II/Apolipoprotein C2 |
|---|
| Organism | Bos taurus |
|---|
| Uniprot ID | P19034 |
|---|
| Milk Fraction | Whey |
|---|
| Ref Sequence ID | NP_001095850.1 |
|---|
| Aminoacid Length | 101 |
|---|
| Molecular Weight | 11061 |
|---|
| FASTA Sequence |
Download |
|---|
| Gene Name | APOC2 |
|---|
| Gene ID | 618039 |
|---|
| Protein Existence Status | Reviewed |
|---|
Secondary Information |
|---|
| Presence in other biological fluids/tissue/cells | liver |
|---|
| Protein Function | Apolipoprotein C-II (apoC-II) is a critical cofactor for the activation of lipoprotein lipase (LPL), a plasma enzyme that hydrolyzes triglycerides (TG) on TG-rich lipoproteins (TRL).ApoC-II plays a critical role in TRL metabolism by acting as a cofactor of lipoprotein lipase (LPL), the main enzyme that hydrolyses plasma triglycerides (TG) on TRL. |
|---|
| Biochemical Properties | ApoC-II contains only 3 helices and the first helix at the N-terminus, residue 16 to 36 (historical nomenclature, based on residue 1 occurring after signal peptide cleavage) is relatively long and is primarily responsible for lipoprotein binding. It forms a classic Type A amphipathic helix, with a large hydrophobic face, two positively charged residues (Lys) close to the water/lipid interface and three negatively charged residues (Glu) on the hydrophilic side of a helix. This amino acid configuration allows apoC-II to bind tightly to a lipid surface. The second helix is relatively short and only encompasses residues 50−56, and from nuclear magnetic resonance analysis this region appears to be mostly in a random coil configuration. The third helix on the C-terminus (residues 63−76, in historical nomenclature) forms a G-type helix similar to what is commonly found in globular proteins, and does not show a strong polarization of hydrophobic and hydrophilic amino acids, and hence does not bind to lipids avidly |
|---|
| PTMs | proteolytic cleavage |
|---|
Site(s) of PTM(s)
N-glycosylation,
O-glycosylation,
Phosphorylation
| na |
|---|
| Predicted Disorder Regions | NA |
|---|
| DisProt Annotation | |
|---|
| TM Helix Prediction | No TM helices |
|---|
| Significance of PTMs | Proapolipoprotein C-II undergoes proteolytic cleavage of its N-terminal hexapeptide to generate apolipoprotein C-II. |
|---|
| Bibliography | 1.Wolska A, Reimund M, Remaley AT. Apolipoprotein C-II: the re-emergence of a forgotten factor. Curr Opin Lipidol. 2020 Jun;31(3):147-153. doi: 10.1097/MOL.0000000000000680. PMID: 32332429. 2.MacRaild CA, Hatters DM, Howlett GJ, et al. NMR Structure of Human Apolipoprotein C-II in the Presence of Sodium Dodecyl Sulfate. Biochemistry. 2001;40:5414–5421. 3. Segrest JP, Jones MK, De Loof H, et al. The amphipathic helix in the exchangeable apolipoproteins: a review of secondary structure and function. J Lipid Res. 1992;33:141–166. |
|---|
