Recombinant Mouse Matrilin-2 Protein

Matrilin-2 is an extracellular matrix protein that belongs to the superfamily of von Willebrand factor A domain (VWA) containing proteins. It is expressed in many tissues and functions as a bridging component between other matrix molecules (1, 2, 3, 4). The mouse Matrilin-2 cDNA encodes a 956 amino acid (aa) precursor with a 23 aa signal sequence, two VWA domains separated by ten tandem EGF-like repeats, and a C-terminal coiled coil domain (5). Mouse Matrilin-2 shares 84%-87% aa sequence identity with human, rat, and canine Matrilin-2, and 26%, 21%, and 34% aa sequence identity with mouse Matrilin-1, -3, and -4, respectively. Matrilin-2 forms a variety of disulfide-linked oligomers via its coiled coil domain (4, 6-8). It can assemble into homotrimers or heterotrimers with Matrilin-1 and/or Matrilin-4 (4, 6, 7) but has not been detected in heterotrimers containing Matrilin-3 (7). The VWA domains are thought to mediate Matrilin-Matrilin interactions as well as interactions with other matrix proteins such as Fibronectin, Collagen I, Fibrilin-2, and Laminin-1/Nidogen-1 complexes (6). Matrilin-2 knockout mice do not display any obvious abnormalities, suggesting that the expression of other molecules can compensate for the lack of Matrilin-2 (9).