MMP14:TIMP2 MMP14:TIMP2:proMMP2 MMP14:TIMP2 binds proMMP2 Authored: Jupe, S, 2011-09-09 Edited: Jupe, S, 2012-02-21 Pubmed10947989 Pubmed11325829 Pubmed12374789 Pubmed18974156 Pubmed9182583 Pubmed9422744 Pubmed9632662 Pubmed9685420 Pubmed9933646 Reactome Database ID Release 431604350 Reactome, http://www.reactome.org ReactomeREACT_118860 Reviewed: Butler, GS, 2012-02-28 Reviewed: Overall, CM, 2012-02-28 The MMP14:TIMP2 complex can efficiently bind proMMP2. Physiological concentrations of TIMP2 enhance proMMP2 binding, but higher concentrations inhibit proMMP2 activation (Butler et al. 1998, Kinoshita et al. 1998), indicating that while MMP14:TIMP2 complexes bind proMMP2, local free MMP14 cleaves the TIMP-bound proMMP2 in the prodomain, leading to autoactivation between Asn109 Tyr110. In vivo the majority of MMP14 (MT1-MMP) is bound to TIMP2 and therefore functions as a receptor for proMMP2 (Nishida et al. 2008). Binding of TIMP-2 to proMMP2 occurs via interaction of the TIMP2 C domain (McQuibban et al. 2000) and the MMP2 hemopexin domain between hemopexin blades III and IV (Overall et al. 1999) in an interaction that is highly dependant upon the nature of the C-tail of the TIMP (Kai et al. 2002). TIMP-4 also binds the proMMP2 hemopexin domain (Bigg et al. 1997) to prevent activation by MMP14 (Bigg et al. 2001). An alternative cell surface localization mechanism exists that inhibits MMP2 activation: Cell surface Beta1 integrin binds native type I collagen, which in turn is bound by the fibronectin type II modules of MMP2 to prevent activation by MMP14 (Steffensen et al. 1998).