Lectican

Lecticans, also known as hyalectans, are a family of large chondroitin sulfate proteoglycans found in the extracellular matrix. There are four members of the lectican family: aggrecan, brevican, neurocan, and versican.¹ Lecticans interact with hyaluronic acid and tenascin-R to form a ternary complex.²

Aggrecan and versican are widely distributed throughout all tissues. Where aggrecan is a major extracellular matrix constituent in cartilage, versican is widely expressed in a number of connective tissues, including those in vascular smooth muscle, skin, and the cells of central and peripheral nervous systems.³ Brevican and neurocan are primarily restricted to the central nervous system (CNS)²³ and are particularly abundant in perineuronal nets.⁴

All four lecticans contain an N-terminal globular domain (G1 domain) that in turn contains an immunoglobulin V-set domain and a Link domain that binds hyaluronic acid; a long extended central domain (CS) that is modified with covalently attached sulfated glycosaminoglycan chains, and a C-terminal globular domain (G3 domain) containing one or more EGF repeats, a C-type lectin domain and a CRP-like domain. Aggrecan has in addition a globular domain (G2 domain) that is situated between the G1 and CS domains.²