COL18A1, Official Symbol COL18A1provided by HGNC Official Full Name collagen type XVIII alpha 1 chainprovided by HGNC Primary source HGNC:HGNC:2195 See related Ensembl:ENSG00000182871 MIM:120328; AllianceGenome:HGNC:2195 Gene type protein coding RefSeq status REVIEWED Organism Homo sapiens Lineage Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo Also known as KS; KNO; GLCC; KNO1 Summary This gene encodes the alpha chain of type XVIII collagen. This collagen is one of the multiplexins, extracellular matrix proteins that contain multiple triple-helix domains (collagenous domains) interrupted by non-collagenous domains. A long isoform of the protein has an N-terminal domain that is homologous to the extracellular part of frizzled receptors. Proteolytic processing at several endogenous cleavage sites in the C-terminal domain results in production of endostatin, a potent antiangiogenic protein that is able to inhibit angiogenesis and tumor growth. Mutations in this gene are associated with Knobloch syndrome. The main features of this syndrome involve retinal abnormalities, so type XVIII collagen may play an important role in retinal structure and in neural tube closure. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014] Annotation information Annotation category: suggests misassembly Expression Ubiquitous expression in liver (RPKM 68.9), kidney (RPKM 46.2) and 24 other tissues See more Orthologs mouse all