5EZD

Crystal structure of a Hepatocyte growth factor activator inhibitor-1 (HAI-1) fragment covering the PKD-like 'internal' domain and Kunitz domain 1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.220 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal Structure of a Two-domain Fragment of Hepatocyte Growth Factor Activator Inhibitor-1: FUNCTIONAL INTERACTIONS BETWEEN THE KUNITZ-TYPE INHIBITOR DOMAIN-1 AND THE NEIGHBORING POLYCYSTIC KIDNEY DISEASE-LIKE DOMAIN.

Hong, Z.De Meulemeester, L.Jacobi, A.Pedersen, J.S.Morth, J.P.Andreasen, P.A.Jensen, J.K.

(2016) J.Biol.Chem. 291: 14340-14355

  • DOI: 10.1074/jbc.M115.707240

  • PubMed Abstract: 
  • Hepatocyte growth factor activator inhibitor-1 (HAI-1) is a type I transmembrane protein and inhibitor of several serine proteases, including hepatocyte growth factor activator and matriptase. The protein is essential for development as knock-out mic ...

    Hepatocyte growth factor activator inhibitor-1 (HAI-1) is a type I transmembrane protein and inhibitor of several serine proteases, including hepatocyte growth factor activator and matriptase. The protein is essential for development as knock-out mice die in utero due to placental defects caused by misregulated extracellular proteolysis. HAI-1 contains two Kunitz-type inhibitor domains (Kunitz), which are generally thought of as a functionally self-contained protease inhibitor unit. This is not the case for HAI-1, where our results reveal how interdomain interactions have evolved to stimulate the inhibitory activity of an integrated Kunitz. Here we present an x-ray crystal structure of an HAI-1 fragment covering the internal domain and Kunitz-1. The structure reveals not only that the previously uncharacterized internal domain is a member of the polycystic kidney disease domain family but also how the two domains engage in interdomain interactions. Supported by solution small angle x-ray scattering and a combination of site-directed mutagenesis and functional assays, we show that interdomain interactions not only stabilize the fold of the internal domain but also stimulate the inhibitory activity of Kunitz-1. By completing our structural characterization of the previously unknown N-terminal region of HAI-1, we provide new insight into the interplay between tertiary structure and the inhibitory activity of a multidomain protease inhibitor. We propose a previously unseen mechanism by which the association of an auxiliary domain stimulates the inhibitory activity of a Kunitz-type inhibitor (i.e. the first structure of an intramolecular interaction between a Kunitz and another domain).


    Organizational Affiliation

    From the Department of Molecular Biology and Genetics, Danish-Chinese Centre for Proteases and Cancer, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C, Denmark.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Kunitz-type protease inhibitor 1
A, B
145Homo sapiensMutation(s): 0 
Gene Names: SPINT1 (HAI1)
Find proteins for O43278 (Homo sapiens)
Go to Gene View: SPINT1
Go to UniProtKB:  O43278
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

Download SDF File 
Download CCD File 
A, B
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
ACT
Query on ACT

Download SDF File 
Download CCD File 
B
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.220 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 57.650α = 90.00
b = 75.140β = 90.00
c = 75.260γ = 90.00
Software Package:
Software NamePurpose
xia2data reduction
PHASERphasing
PHENIXrefinement
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Danish Cancer SocietyDenmarkNA

Revision History 

  • Version 1.0: 2016-05-18
    Type: Initial release
  • Version 1.1: 2016-06-01
    Type: Database references
  • Version 1.2: 2016-07-13
    Type: Database references