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: Samuni U,Dantsker D,Juszczak LJ,Bettati S,Ronda L,Mozzarelli A,Friedman JM

    更新日期:2004-11-02 00:00:00

  • Discovery of a Kojibiose Phosphorylase in Escherichia coli K-12.

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    pub_type: 杂志文章


    authors: Mukherjee K,Narindoshvili T,Raushel FM

    更新日期:2018-05-15 00:00:00

  • The complete amino acid sequence of the major component myoglobin of dwarf sperm whale (Kogia simus).

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    pub_type: 杂志文章


    authors: Dwulet FE,Jones BN,Lehman LD,Gurd FR

    更新日期:1977-03-08 00:00:00

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    abstract::The Co and Fe K-edge extended X-ray absorption fine structure (EXAFS) spectra of the methionyl aminopeptidase from Escherichia coli (EcMetAP) have been recorded in the presence of 1 and 2 equiv of either Co(II) or Fe(II) (i.e., [Co(II)_(EcMetAP)], [Co(II)Co(II)(EcMetAP)], [Fe(II)_(EcMetAP)], and [Fe(II)Fe(II)(EcMetAP)...


    pub_type: 杂志文章


    authors: Cosper NJ,D'souza VM,Scott RA,Holz RC

    更新日期:2001-11-06 00:00:00

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    pub_type: 杂志文章


    authors: Stoeckler JD,Cambor C,Parks RE Jr

    更新日期:1980-01-08 00:00:00

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    pub_type: 杂志文章


    authors: Takeuchi Y,Tanaka S,Matsumura H,Koga Y,Takano K,Kanaya S

    更新日期:2009-11-10 00:00:00

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    pub_type: 杂志文章


    authors: Jayasena SD,Johnston BH

    更新日期:1992-01-21 00:00:00

  • Inactivation of Met471Cys tyramine β-monooxygenase results from site-specific cysteic acid formation.

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    pub_type: 杂志文章


    authors: Osborne RL,Zhu H,Iavarone AT,Hess CR,Klinman JP

    更新日期:2012-09-25 00:00:00

  • Structures of gangliosides from bovine adrenal medulla.

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    pub_type: 杂志文章


    authors: Price H,Kundu S,Ledeen R

    更新日期:1975-04-08 00:00:00

  • Assignment of a ligand in stellacyanin by a pulsed electron paramagnetic resonance method.

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    pub_type: 杂志文章


    authors: Mims WB,Peisach J

    更新日期:1976-08-24 00:00:00

  • Effects of temperature and viscosity on R67 dihydrofolate reductase catalysis.

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    pub_type: 杂志文章


    authors: Chopra S,Lynch R,Kim SH,Jackson M,Howell EE

    更新日期:2006-05-30 00:00:00

  • Thrombin inactivates acidic fibroblast growth factor but not basic fibroblast growth factor.

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    pub_type: 杂志文章


    authors: Lobb RR

    更新日期:1988-04-05 00:00:00

  • Observations on the pyridoxal 5'-phosphate inhibition of DNA polymerases.

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    pub_type: 杂志文章


    authors: Modak MJ

    更新日期:1976-08-10 00:00:00

  • Mapping of steroids binding to 17 beta-hydroxysteroid dehydrogenase type 1 using Monte Carlo energy minimization reveals alternative binding modes.

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    pub_type: 杂志文章


    authors: Blanchet J,Lin SX,Zhorov BS

    更新日期:2005-05-17 00:00:00

  • A structural basis for the regulation of an H-NOX-associated cyclic-di-GMP synthase/phosphodiesterase enzyme by nitric oxide-bound H-NOX.

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    pub_type: 杂志文章


    authors: Lahiri T,Luan B,Raleigh DP,Boon EM

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    pub_type: 杂志文章


    authors: Xiao Y,Nieves E,Angeletti RH,Orr GA,Wolkoff AW

    更新日期:2006-03-14 00:00:00

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    authors: Biro A,Ling WL,Arlaud GJ

    更新日期:2010-03-16 00:00:00

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    pub_type: 杂志文章


    authors: Han J,Burke JM

    更新日期:2005-05-31 00:00:00

  • Insights into the Mechanism of the Cyanobactin Heterocyclase Enzyme.

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  • Effects of mutations in M4 of the gastric H+,K+-ATPase on inhibition kinetics of SCH28080.

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    pub_type: 杂志文章


    authors: Munson KB,Lambrecht N,Sachs G

    更新日期:2000-03-21 00:00:00

  • Plasminogen activation is stimulated by prion protein and regulated in a copper-dependent manner.

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    pub_type: 杂志文章


    authors: Ellis V,Daniels M,Misra R,Brown DR

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  • Evidence for the involvement of Ala 166 in coupling Na(+) to sugar transport through the human Na(+)/glucose cotransporter.

    abstract::We mutated residue 166, located in the putative Na(+) transport pathway between transmembrane segments 4 and 5 of human Na(+)/glucose cotransporter (hSGLT1), from alanine to cysteine (A166C). A166C was expressed in Xenopus laevis oocytes, and electrophysiological methods were used to assay function. The affinity for N...


    pub_type: 杂志文章


    authors: Meinild AK,Loo DD,Hirayama BA,Gallardo E,Wright EM

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    pub_type: 杂志文章


    authors: Burghardt TP,Ajtai K

    更新日期:1994-05-10 00:00:00

  • Membrane Docking of the Synaptotagmin 7 C2A Domain: Electron Paramagnetic Resonance Measurements Show Contributions from Two Membrane Binding Loops.

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    pub_type: 杂志文章


    authors: Osterberg JR,Chon NL,Boo A,Maynard FA,Lin H,Knight JD

    更新日期:2015-09-22 00:00:00

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    pub_type: 杂志文章


    authors: Slomiany BL,Slomiany A,Glass GB

    更新日期:1977-09-06 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

    更新日期:2004-01-20 00:00:00

  • Human platelet glycoproteins V and IX: mapping of two leucine-rich glycoprotein genes to chromosome 3 and analysis of structures.

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    pub_type: 杂志文章


    authors: Yagi M,Edelhoff S,Disteche CM,Roth GJ

    更新日期:1995-12-12 00:00:00

  • Kinetic characterization of the carbon monoxide-acetyl-CoA (carbonyl group) exchange activity of the acetyl-CoA synthesizing CO dehydrogenase from Clostridium thermoaceticum.

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    pub_type: 杂志文章


    authors: Raybuck SA,Bastian NR,Orme-Johnson WH,Walsh CT

    更新日期:1988-10-04 00:00:00

  • Retardation of Folding Rates of Substrate Proteins in the Nanocage of GroEL.

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    pub_type: 杂志文章


    authors: Koculi E,Thirumalai D

    更新日期:2021-01-19 00:00:00

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    pub_type: 杂志文章


    authors: Rastegar-Lari G,Villoutreix BO,Ribba AS,Legendre P,Meyer D,Baruch D

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