Regulation of insulin-regulated membrane aminopeptidase activity by its C-terminal domain.


:The development of inhibitors of insulin-regulated aminopeptidase (IRAP), a membrane-bound zinc metallopeptidase, is a promising approach for the discovery of drugs for the treatment of memory loss such as that associated with Alzheimer's disease. There is, however, no consensus in the literature about the mechanism by which inhibition occurs. Sequence alignments, secondary structure predictions, and homology models based on the structures of recently determined related metallopeptidases suggest that the extracellular region consists of four domains. Partial proteolysis and mass spectrometry reported here confirm some of the domain boundaries. We have produced purified recombinant fragments of human IRAP on the basis of these data and examined their kinetic and biochemical properties. Full-length extracellular constructs assemble as dimers with different nonoverlapping fragments dimerizing as well, suggesting an extended dimer interface. Only recombinant fragments containing domains 1 and 2 possess aminopeptidase activity and bind the radiolabeled hexapeptide inhibitor, angiotensin IV (Ang IV). However, fragments lacking domains 3 and 4 possess reduced activity, although they still bind a range of inhibitors with the same affinity as longer fragments. In the presence of Ang IV, IRAP is resistant to proteolysis, suggesting significant conformational changes occur upon binding of the inhibitor. We show that IRAP has a second Zn(2+) binding site, not associated with the catalytic region, which is lost upon binding Ang IV. Modulation of activity caused by domains 3 and 4 is consistent with a conformational change regulating access to the active site of IRAP.






Ascher DB,Cromer BA,Morton CJ,Volitakis I,Cherny RA,Albiston AL,Chai SY,Parker MW




Has Abstract


2011-04-05 00:00:00












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    pub_type: 杂志文章


    authors: Harrelson JP,Atkins WM,Nelson SD

    更新日期:2008-03-04 00:00:00

  • Scaffolding functions of arrestin-2 revealed by crystal structure and mutagenesis.

    abstract::Arrestin binding to activated, phosphorylated G protein-coupled receptors (GPCRs) represents a critical step in regulation of light- and hormone-dependent signaling. Nonvisual arrestins, such as arrestin-2, interact with multiple proteins for the purpose of propagating and terminating signaling events. Using a combina...


    pub_type: 杂志文章


    authors: Milano SK,Pace HC,Kim YM,Brenner C,Benovic JL

    更新日期:2002-03-12 00:00:00

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    abstract::Most duplex DNAs that are in the "B" conformation are not immunogenic. One important exception is poly(dG) X poly(dC), which produces a good immune response even though, by many criteria, it adopts a conventional right-handed helix. In order to investigate what features are being recognized, monoclonal antibodies were...


    pub_type: 杂志文章


    authors: Lee JS,Woodsworth ML,Latimer LJ

    更新日期:1984-07-03 00:00:00

  • Ultraviolet resonance Raman spectra of cytochrome c conformational states.

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    pub_type: 杂志文章


    authors: Copeland RA,Spiro TG

    更新日期:1985-08-27 00:00:00

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    abstract::The relaxin-like factor (RLF) is a circulating hormone that is synthesized in the gonads of mammals and released into the bloodstream. The distribution of its receptor and a trace of cross-reactivity to relaxin receptors implied that this relatively new factor is more relaxin- than insulin-like. The chemical synthesis...


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    authors: Büllesbach EE,Schwabe C

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  • Perturbation of microtubule polymerization by quercetin through tubulin binding: a novel mechanism of its antiproliferative activity.

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    pub_type: 杂志文章


    authors: Gupta K,Panda D

    更新日期:2002-10-29 00:00:00

  • 51V NMR study of vanadate binding to myosin and its subfragment 1.

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    pub_type: 杂志文章


    authors: Ringel I,Peyser YM,Muhlrad A

    更新日期:1990-09-25 00:00:00

  • Correlation of photolabeling with occupancy of cAMP binding sites in the regulatory subunit of cAMP-dependent protein kinase I.

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    pub_type: 杂志文章


    authors: Bubis J,Taylor SS

    更新日期:1987-06-16 00:00:00

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    pub_type: 杂志文章


    authors: Reed JR,Quilici DR,Blomquist GJ,Reitz RC

    更新日期:1995-12-12 00:00:00

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    pub_type: 杂志文章


    authors: Zeng W,Seward HE,Málnási-Csizmadia A,Wakelin S,Woolley RJ,Cheema GS,Basran J,Patel TR,Rowe AJ,Bagshaw CR

    更新日期:2006-09-05 00:00:00

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    pub_type: 杂志文章


    authors: Kampranis SC,Gormley NA,Tranter R,Orphanides G,Maxwell A

    更新日期:1999-02-16 00:00:00

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    pub_type: 杂志文章


    authors: Reed BC,Rilling HC

    更新日期:1975-01-14 00:00:00

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    pub_type: 杂志文章


    authors: Xu RX,Meadows RP,Fesik SW

    更新日期:1993-03-16 00:00:00

  • Trihydroxynaphthalene reductase from Magnaporthe grisea: realization of an active center inhibitor and elucidation of the kinetic mechanism.

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    pub_type: 杂志文章


    authors: Thompson JE,Basarab GS,Andersson A,Lindqvist Y,Jordan DB

    更新日期:1997-02-18 00:00:00

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    pub_type: 杂志文章


    authors: Quinn DM,Shirai K,Jackson RL,Harmony JA

    更新日期:1982-12-21 00:00:00

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    pub_type: 杂志文章


    authors: Srivenugopal KS,Yuan XH,Friedman HS,Ali-Osman F

    更新日期:1996-01-30 00:00:00

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    pub_type: 杂志文章


    authors: Yeh JI,Charrier V,Paulo J,Hou L,Darbon E,Claiborne A,Hol WG,Deutscher J

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    pub_type: 杂志文章


    authors: Arias HR,Bhumireddy P,Spitzmaul G,Trudell JR,Bouzat C

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  • Characterization of the carboxylate delivery module of transcarboxylase: following spontaneous decarboxylation of the 1.3S-CO2- subunit by NMR and FTIR spectroscopies.

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    pub_type: 杂志文章


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    更新日期:2002-02-19 00:00:00

  • Transport of newly synthesized sterol to the sterol-enriched plasma membrane occurs via nonvesicular equilibration.

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    pub_type: 杂志文章


    authors: Baumann NA,Sullivan DP,Ohvo-Rekilä H,Simonot C,Pottekat A,Klaassen Z,Beh CT,Menon AK

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  • Loss of DNA minor groove interactions by exonuclease-deficient Klenow polymerase inhibits O6-methylguanine and abasic site translesion synthesis.

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    pub_type: 杂志文章


    authors: Gestl EE,Eckert KA

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    pub_type: 杂志文章


    authors: Bhattacharyya S,Griep MA

    更新日期:2000-02-01 00:00:00

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    pub_type: 杂志文章


    authors: Northrop DB,Cho YK

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    pub_type: 杂志文章


    authors: Wolbring G,Baehr W,Palczewski K,Schnetkamp PP

    更新日期:1999-03-02 00:00:00

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    pub_type: 杂志文章


    authors: Schlodder E,Falkenberg K,Gergeleit M,Brettel K

    更新日期:1998-06-30 00:00:00

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    pub_type: 杂志文章


    authors: Reisler E,Burke M,Harrington WF

    更新日期:1977-11-29 00:00:00

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    pub_type: 杂志文章


    authors: Driessen RP,Sitters G,Laurens N,Moolenaar GF,Wuite GJ,Goosen N,Dame RT

    更新日期:2014-10-21 00:00:00

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    pub_type: 杂志文章


    authors: Kördel J,Forsén S,Chazin WJ

    更新日期:1989-08-22 00:00:00

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    pub_type: 杂志文章


    authors: Fujimaki K,Yamazaki T,Taniwaki M,Ichinose A

    更新日期:1998-05-12 00:00:00

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    pub_type: 杂志文章


    authors: Miller D,Xu H,White RH

    更新日期:2012-04-10 00:00:00