Matrilin-3 is a protein that in humans is encoded by the MATN3 gene. It is linked to the development of many types of cartilage, and part of the Matrilin family, which includes Matrilin-1, Matrilin-2, Matrilin-3, and Matrilin-4, a family of filamentous-forming adapter oligomeric extracellular proteins that are linked to the formation of cartilage and bone, as well as maintaining homeostasis after development. It is considered an extracellular matrix protein that functions as an adapter protein where the Matrilin-3 subunit can form both homo-tetramers and hetero-oligomers with subunits from Matrilin-1 which is the cartilage matrix protein. This restricted tissue has been strongly expressed in growing skeletal tissue as well as cartilage and bone.( PMID:26499313, 27104523, 11950247)