Spondin 2 (SPON2)

The full-length SPON2 cDNA encodes a 331-amino acid protein with a domain organization similar to those of zebrafish mindin-1/mindin-2 and F-spondin (SPON1): a hydrophobic signal sequence in the N terminus, an FS1 domain, an FS2 domain, and a thrombospondin type I repeat.

The mouse mindin protein, which is 85% identical to the human protein, is a conserved member of a family of secreted extracellular matrix proteins. RNA blot analysis detected expression in a variety of tissues, with abundant expression in lung and lymphoid tissues. Immunoblot blot analysis showed expression of a 42-kD protein under reducing conditions and expression of dimers and oligomers in a concentration-dependent manner under nonreducing conditions.