title: Biosynthetic processing of the Pro-alpha1(V)Pro-alpha2(V)Pro-alpha3(V) procollagen heterotrimer.
abstract: Type V collagen is a quantitatively minor fibrillar collagen comprised of different chain compositions in different tissues. The most widely distributed form, an alpha1(V)2alpha2(V) heterotrimer, regulates the physical properties of type I/V heterotypic collagen fibrils via partially processed NH2-terminal globular sequences. A less characterized alpha1(V)alpha2(V)alpha3(V) heterotrimer has a much more limited distribution of expression and unknown function(s). We characterized the biosynthetic processing of pro-alpha1(V)2pro-alpha2(V) procollagen previously and showed it to differ in important ways from biosynthetic processing of the major fibrillar procollagens I-III. Here we have successfully produced recombinant pro-alpha1(V)pro-alpha2(V)pro-alpha3(V) heterotrimers. We use these, and mouse embryo fibroblasts doubly homozygous null for the Bmp1 gene, which encodes the metalloproteinase bone morphogenetic protein-1 (BMP-1), and for a gene encoding the closely related metalloproteinase mammalian Tolloid-like 1, to characterize biosynthetic processing of pro-alpha1(V)pro-alpha2(V)pro-alpha3(V) heterotrimers, thus completing characterization of type V collagen biosynthetic processing. Whereas pro-alpha1(V) and pro-alpha2(V) processing in pro-alpha1(V)pro-alpha2(V)pro-alpha3(V) heterotrimers is similar to that which occurs in pro-alpha1(V)2pro-alpha2(V) heterotrimers, the processing of pro-alpha3(V) by BMP-1 occurs at an unexpected site within NH2-terminal globular sequences. We also demonstrate that, despite similarities in NH2-terminal domain structures, pro-alpha2(V) NH2-terminal globular sequences are not cleaved by ADAMTS-2, the metalloproteinase that cleaves the N-propeptides of the major fibrillar procollagen chains.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Bagavathi
authors.initials: B
authors.lastname: Gopalakrishnan
authors.forename: Wei-Man
authors.initials: WM
authors.lastname: Wang
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Greenspan
mesh_terms: D051722:ADAM Proteins; D000071096:ADAMTS Proteins; D000071121:ADAMTS4 Protein; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D055395:Bone Morphogenetic Protein 1; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D003094:Collagen / Q000737:chemistry* / Q000378:metabolism; D024042:Collagen Type I / Q000737:chemistry* / Q000378:metabolism; D019281:Dimerization; D005347:Fibroblasts / Q000378:metabolism; D045683:Furin / Q000737:chemistry; D006720:Homozygote; D006801:Humans; D015151:Immunoblotting; D008666:Metalloendopeptidases / Q000378:metabolism; D051379:Mice; D008954:Models, Biological; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011348:Procollagen N-Endopeptidase / Q000737:chemistry; D011487:Protein Conformation; D011498:Protein Precursors / Q000737:chemistry* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D014162:Transfection
chemical_list: D019485:Bone Morphogenetic Proteins; D024042:Collagen Type I; D011498:Protein Precursors; D011994:Recombinant Proteins; C426047:pro-alpha1(V-XI) collagen; C406808:pro-alpha3(V) collagen; D003094:Collagen; D045683:Furin; D051722:ADAM Proteins; D000071096:ADAMTS Proteins; D008666:Metalloendopeptidases; C000609307:ADAMTS2 protein, human; C000609308:Adamts2 protein, mouse; D011348:Procollagen N-Endopeptidase; C525705:BMP1 protein, human; C525707:Bmp1 protein, mouse; D055395:Bone Morphogenetic Protein 1; D000071121:ADAMTS4 Protein