In addition to fibronectin, previously identified as an ADAMTS9 substrate and other ECM and secreted proteins and proteoglycans, the present work also identified the cilium transition zone protein TMEM67, which like ADAMTS9, is mutated in ciliopathies as a potential substrate, warranting further investigation of TMEM67 processing in the context of ciliogenesis (86, 87, 88). Here, TMEM67 is linked to ciliopathy.