Figure 2. G1 fragments in Jaffa and wild-type cartilage extracts.

(A) The domain structure of the aggrecan core protein, with 2 N-terminal globular domains, G1 and G2, and a C-terminal G3 domain. The extended region between G2 and G3 is heavily substituted with CS chains (wavy lines). Aggrecanase and MMP cleavage site sequences in the mouse IGD and CS-2 domains are shown, and amino acids that are different in human aggrecan are shown above. Numbering corresponds with the mouse sequence. (B) Cartilage extracts from wild-type and Jaffa mice were analyzed for VTEGE³⁷³ or DIPEN³⁴¹ neoepitopes. (C) Dialyzed extracts of equal cartilage wet weight from wild-type and Jaffa mice were digested with or without recombinant human ADAMTS-5 and analyzed for the VTEGE³⁷³ and ³⁷⁴ALGSV neoepitopes. Stripping and reprobing the membranes with monoclonal antibody 2B6 confirmed sample loading in each lane (data not shown).