This gene encodes a type IV collagen alpha protein. Type IV collagen proteins are integral components of basement membranes. This gene shares a bidirectional promoter with a paralogous gene on the opposite strand. The protein consists of an amino-terminal 7S domain, a triple-helix forming collagenous domain, and a carboxy-terminal non-collagenous domain. It functions as part of a heterotrimer and interacts with other extracellular matrix components such as perlecans, proteoglycans, and laminins. In addition, proteolytic cleavage of the non-collagenous carboxy-terminal domain results in a biologically active fragment known as arresten, which has anti-angiogenic and tumor suppressor properties. Mutations in this gene cause porencephaly, cerebrovascular disease, and renal and muscular defects. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]
Forensic Context
A study in mice selectively bred for high or low methamphetamine intake identified the COL4A1 as a gene overexpressed in the ventral midbrain of the low-drinking line and as an extracellular matrix component [Hitzemann et al. DOI:10.3390/brainsci9070155]. In human neonates with hypoxic-ischemic encephalopathy, the COL4A1 was a significant gene over time associated with adverse outcomes in a high-income country cohort, identified as a HIF1 target with expression increasing after oxidative stress [Montaldo et al. DOI:10.1001/jamanetworkopen.2023.54433]. In human corpus cavernosum tissue, single-cell transcriptome analysis revealed that the COL4A1 had higher expression in fibroblasts from patients with erectile dysfunction compared to normal controls, and its expression was upregulated in fibroblasts treated with a WNT pathway activator in functional experiments [Zhao et al. DOI:10.1038/s41467-022-31950-9].