First Author | Piecha D | Year | 1999 |
Journal | J Biol Chem | Volume | 274 |
Issue | 19 | Pages | 13353-61 |
PubMed ID | 10224097 | Mgi Jnum | J:54894 |
Mgi Id | MGI:1336568 | Doi | 10.1074/jbc.274.19.13353 |
Citation | Piecha D, et al. (1999) Matrilin-2, a large, oligomeric matrix protein, is expressed by a great variety of cells and forms fibrillar networks. J Biol Chem 274(19):13353-61 |
abstractText | Matrilin-2 is a member of the protein superfamily with von Willebrand factor type A-like modules. Mouse matrilin-2 cDNA fragments were expressed in 293-EBNA cells, and the protein was purified, characterized, and used to immunize rabbits. The affinity-purified antiserum detects matrilin-2 in dense and loose connective tissue structures, subepithelial connective tissue of the skin and digestive tract, specialized cartilages, and blood vessel walls. In situ hybridization of 35S-labeled riboprobes localizes the matrilin-2 mRNA to fibroblasts of dermis, tendon, ligaments, perichondrium, and periosteum; connective tissue elements in the heart; smooth muscle cells; and epithelia and loose connective tissue cells of the alimentary canal and respiratory tract. RNA blot hybridization and immunoblotting revealed both matrilin-2 mRNA and protein in cultures of a variety of cell types, confirming the tissue distribution. Alternative splicing affects a module unique for matrilin-2 in all of the above RNA sources. SDS-polyacrylamide gel electrophoresis and electron microscopy reveals matrilin-2 from tissue extracts and cell line cultures as a mixture of mono-, di-, tri-, and tetramers. Matrilin-2 is substituted with N-linked oligosaccharides but not with glycosaminoglycans. Because of other, yet unidentified, cell-type dependent posttranslational modifications, the monomer is heterogeneous in size. Immunofluorescence showed that matrilin-2 functions by forming an extracellular, filamentous network. |