Fig. 1. The TGFß large latent complex (LLC). The LLC comprises TGFß
(black), LAP (red) and LTBP. TGFß and LAP are proteolytically separated
at the site indicated by the arrowhead. After processing, TGFß remains
noncovalently associated with LAP. LAP and LTBP are joined by disulfide bonds
(light blue lines). The LLC is covalently linked to the extracellular matrix
(ECM) through an isopeptide bond (green) between the N-terminus of LTBP
(somewhere between EGF2 and the hinge domain) and a currently unidentified
matrix protein. The hinge domain (arrow) of LTBP is a protease-sensitive
region that allows LLC to be proteolytically released from the ECM.