title: On the origins of the extracellular matrix in vertebrates.
abstract: Extracellular matrix (ECM) is a key metazoan characteristic. In addition to providing structure and orientation to tissues, it is involved in many cellular processes such as adhesion, migration, proliferation and differentiation. Here we provide a comprehensive analysis of ECM molecules focussing on when vertebrate specific matrices evolved. We identify 60 ECM genes and 20 associated processing enzymes in the genome of the urochordate Ciona intestinalis. A comparison with vertebrate and protostome genomes has permitted the identification of both a core set of metazoan matrix genes and vertebrate-specific innovations in the ECM. We have identified a few potential cases of de novo vertebrate ECM gene innovation, but the majority of ECM genes have resulted from duplication of pre-existing genes present in the ancestral vertebrate. In conclusion, the modern complexity we see in vertebrate ECM has come about largely by duplication and modification of pre-existing matrix molecules. Extracellular matrix genes and their processing enzymes appear to be over-represented in the vertebrate genome suggesting that these genes played an active role enabling and underpinning the evolution of vertebrates.
authors.affiliation: Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester, UK.
authors.forename: Julie
authors.initials: J
authors.lastname: Huxley-Jones
authors.forename: David L
authors.initials: DL
authors.lastname: Robertson
authors.forename: Raymond P
authors.initials: RP
authors.lastname: Boot-Handford
mesh_terms: D000818:Animals; D002938:Ciona intestinalis / Q000235:genetics* / Q000378:metabolism; D003094:Collagen / Q000235:genetics; D004798:Enzymes / Q000235:genetics; D019143:Evolution, Molecular; D005109:Extracellular Matrix / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000235:genetics; D020440:Gene Duplication; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D016023:Integrins / Q000235:genetics; D008957:Models, Genetic; D005810:Multigene Family; D010802:Phylogeny; D011509:Proteoglycans / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates / Q000235:genetics* / Q000378:metabolism
chemical_list: D004798:Enzymes; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D016023:Integrins; D011509:Proteoglycans; D003094:Collagen