Search
collagen 8 alpha-2 (COL8A2, endothelial collagen)
Function:
- macromolecular component of the subendothelium
- major component of the Descemet's membrane (basement membrane) of corneal endothelium)
- also component of the endothelium of blood vessels
- necessary for migration & proliferation of vascular smooth muscle cells
- proteolytically cleaved by neutrophil elastase, in vitro
- Pro at the third position of the tripeptide repeating unit (G-X-Y) are hydroxylated in some or all of the chains
- homotrimers, or heterotrimers in association with COL8A1
- four homotrimers can form a tetrhedron stabilized by central interacting C-terminal NC1 trimers
Structure: contains 1 C1q domain
Compartment:
- secreted, extracellular space
- extracellular matrix, basement membrane
Expression:
- expressed primarily in subendothelium of large blood vessels
- also expressed in arterioles & venules in muscle, heart, kidney, spleen, umbilical cord, liver & lung
- also found in connective tissue layers around hair follicles, around nerve bundles in muscle, in the dura of the optic nerve, in cornea & sclera, & in the perichondrium of cartilage
- in the kidney, expressed in mesangial cells, glomerular endothelial cells, & tubular epithelial cells
- also expressed in mast cells, & in astrocytes during the repair process
- expressed in Descemet's membrane
Pathology:
- possible role in atherogenesis via effect on proliferation of vascular smooth muscle cells
- up-regulated in diabetic nephropathy
- defects in COL8A2 are the cause of
a) corneal dystrophy Fuchs endothelial type 1
b) posterior polymorphous corneal dystrophy type 2
General
collagen subunit
Properties
SIZE: entity length = 703 aa
MW = 67 kD
MOTIF: signal sequence {1-28}
Nonhelical region (NC2) {29-76}
Triple-helical region {77-536}
Nonhelical region (NC1) {537-703}
MOTIF: C1q {570-703}
Database Correlations
OMIM correlations
MORBIDMAP 120252
UniProt P25067
PFAM correlations
Entrez Gene 1296
Kegg hsa:1296
References
- UniProt :accession P25067
- Entrez Gene :accession 1296