Collagen alpha-1(IV) chain

Collagen alpha-1(IV) chain (COL4A1) is a major structural component of basement membranes, forming mesh-like networks with other extracellular matrix proteins. Its C-terminal domain (arresten) possesses anti-angiogenic activity, inhibiting endothelial cell proliferation and migration (UniProt: P02462).

COL4A1 is widely expressed in vascular and neural tissues. Mutations in this gene cause hereditary vascular and cerebral disorders including brain small vessel disease (BSVD1), intracerebral hemorrhage, and leukoencephalopathy, reflecting its critical role in maintaining basement membrane integrity and preventing vascular dysfunction (UniProt: P02462).

COL4A1 is tagged as relevant to Alzheimer's disease in this dataset. In post-mortem AD brain tissue compared to age-matched controls, COL4A1 is upregulated with a mean log2 fold-change of 0.49 (Chaparral AD proteomics). This elevation may reflect amyloid-related vascular pathology or neuroinflammatory remodeling of the brain vasculature in AD, though the functional significance requires further investigation.