title: Double knockout mice reveal a lack of major functional compensation between collagens XV and XVIII.
abstract: Generation of double knockout mice for collagen types XV and XVIII indicated surprisingly that the mice are viable and do not suffer from any new major defects. Although the two collagens are closely related molecules sharing similarities in tissue expression, we conclude that their biological roles are essentially separate, that of type XV in muscle and type XVIII in the eye. Detailed comparisons of the null mice eyes indicated that type XV collagen seems to be involved in the tunica vasculosa lentis regression process, whereas type XVIII is in the regression of vasa hyaloidea propria, and only minor compensatory effects could be detected. Furthermore, the essential role of type XVIII collagen in the eye is highlighted by the occurrence of this collagen in the epithelial basement membranes of the iris and the ciliary body and in the inner limiting membrane of the retina, sites lacking type XV.
authors: Collagen Research Unit, Biocenter Oulu and Department of Medical Biochemistry and Molecular Biology, University of Oulu, P.O. Box 5000, Oulu 90014, Finland.
authors: Ritva
authors: R
authors: Ylikärppä
authors: Lauri
authors: L
authors: Eklund
authors: Raija
authors: R
authors: Sormunen
authors: Anu
authors: A
authors: Muona
authors: Naomi
authors: N
authors: Fukai
authors: Björn R
authors: BR
authors: Olsen
authors: Taina
authors: T
authors: Pihlajaniemi
mesh_terms: D000818:Animals; D002924:Ciliary Body / Q000502:physiology; D003094:Collagen / Q000235:genetics* / Q000502:physiology*; D043170:Collagen Type XVIII / Q000235:genetics* / Q000502:physiology*; D005123:Eye / Q000378:metabolism; D007498:Iris / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: C085811:COL15A1 protein, human; D043170:Collagen Type XVIII; D003094:Collagen