Crystal structure of the TACE-N-TIMP-3 complex
[ADA17_HUMAN] Defects in ADAM17 are a cause of neonatal inflammatory skin and bowel disease (NISBD) [MIM:614328]. NISBD is a disorder characterized by inflammatory features with neonatal onset, involving the skin, hair, and gut. The skin lesions involve perioral and perianal erythema, psoriasiform erythroderma, with flares of erythema, scaling, and widespread pustules. Gastrointestinal symptoms include malabsorptive diarrhea that is exacerbated by intercurrent gastrointestinal infections. The hair is short or broken, and the eyelashes and eyebrows are wiry and disorganized. [TIMP3_HUMAN] Defects in TIMP3 are the cause of Sorsby fundus dystrophy (SFD) [MIM:136900]. SFD is a rare autosomal dominant macular disorder with an age of onset in the fourth decade. It is characterized by loss of central vision from subretinal neovascularization and atrophy of the ocular tissues. Generally, macular disciform degeneration develops in the patients eye within 6 months to 6 years.    
[ADA17_HUMAN] Cleaves the membrane-bound precursor of TNF-alpha to its mature soluble form. Responsible for the proteolytical release of soluble JAM3 from endothelial cells surface. Responsible for the proteolytic release of several other cell-surface proteins, including p75 TNF-receptor, interleukin 1 receptor type II, p55 TNF-receptor, transforming growth factor-alpha, L-selectin, growth hormone receptor, MUC1 and the amyloid precursor protein. Also involved in the activation of Notch pathway (By similarity).  [TIMP3_HUMAN] Complexes with metalloproteinases (such as collagenases) and irreversibly inactivates them by binding to their catalytic zinc cofactor. May form part of a tissue-specific acute response to remodeling stimuli. Known to act on MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-13, MMP-14 and MMP-15.
Publication Abstract from PubMed
TIMP-3 (tissue inhibitor of metalloproteinases 3) is unique among the TIMP inhibitors, in that it effectively inhibits the TNF-alpha converting enzyme (TACE). In order to understand this selective capability of inhibition, we crystallized the complex formed by the catalytic domain of recombinant human TACE and the N-terminal domain of TIMP-3 (N-TIMP-3), and determined its molecular structure with X-ray data to 2.3 A resolution. The structure reveals that TIMP-3 exhibits a fold similar to those of TIMP-1 and TIMP-2, and interacts through its functional binding edge, which consists of the N-terminal segment and other loops, with the active-site cleft of TACE in a manner similar to that of matrix metalloproteinases (MMPs). Therefore, the mechanism of TIMP-3 binding toward TACE is not fundamentally different from that previously elucidated for the MMPs. The Phe34 phenyl side chain situated at the tip of the relatively short sA-sB loop of TIMP-3 extends into a unique hydrophobic groove of the TACE surface, and two Leu residues in the adjacent sC-connector and sE-sF loops are tightly packed in the interface allowing favourable interactions, in agreement with predictions obtained by systematic mutations by Gillian Murphy's group. The combination of favourable functional epitopes together with a considerable flexibility renders TIMP-3 an efficient TACE inhibitor. This structure might provide means to design more efficient TIMP inhibitors of TACE.
Structural determinants of the ADAM inhibition by TIMP-3: crystal structure of the TACE-N-TIMP-3 complex.,Wisniewska M, Goettig P, Maskos K, Belouski E, Winters D, Hecht R, Black R, Bode W J Mol Biol. 2008 Sep 19;381(5):1307-19. Epub 2008 Jul 7. PMID:18638486
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.