4IF8

Structure Of Vaspin

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.08 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history. 


Literature

Vaspin inhibits kallikrein 7 by serpin mechanism

Heiker, J.T., Kloting, N., Kovacs, P., Kuettner, E.B., Strater, N., Schultz, S., Kern, M., Stumvoll, M., Bluher, M., Beck-Sickinger, A.G.

(2013) Cell Mol Life Sci 70: 2569-2583

  • DOI: 10.1007/s00018-013-1258-8
  • Primary Citation of Related Structures:  
    4IF8

  • PubMed Abstract: 

    • The molecular target of the adipokine vaspin (visceral adipose tissue-derived serpin; serpinA12) and its mode of action are unknown. Here, we provide the vaspin crystal structure and identify human kallikrein 7 (hK7) as a first protease target of vaspin inhibited by classical serpin mechanism with high specificity in vitro ...

    The molecular target of the adipokine vaspin (visceral adipose tissue-derived serpin; serpinA12) and its mode of action are unknown. Here, we provide the vaspin crystal structure and identify human kallikrein 7 (hK7) as a first protease target of vaspin inhibited by classical serpin mechanism with high specificity in vitro. We detect vaspin-hK7 complexes in human plasma and find co-expression of both proteins in murine pancreatic β-cells. We further demonstrate that hK7 cleaves human insulin in the A- and B-chain. Vaspin treatment of isolated pancreatic islets leads to increased insulin concentration in the media upon glucose stimulation without influencing insulin secretion. By application of vaspin and generated inactive mutants, we find the significantly improved glucose tolerance in C57BL/6NTac and db/db mice treated with recombinant vaspin fully dependent on the vaspin serpin activity and not related to vaspin-mediated changes in insulin sensitivity as determined by euglycemic-hyperinsulinemic clamp studies. Improved glucose metabolism could be mediated by increased insulin plasma concentrations 150 min after a glucose challenge in db/db mice, supporting the hypothesis that vaspin may inhibit insulin degradation by hK7 in the circulation. In conclusion, we demonstrate the inhibitory serpin nature and the first protease target of the adipose tissue-derived serpin vaspin, and our findings suggest hK7 inhibition by vaspin as an underlying physiological mechanism for its compensatory actions on obesity-induced insulin resistance.

    Organizational Affiliation: 

    Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, Universität Leipzig, Brüderstraße 34, Leipzig, Germany.



Macromolecules
Find similar proteins by: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Serpin A12 A, B414Homo sapiensMutation(s): 0 
Gene Names: SERPINA12
Find proteins for Q8IW75 (Homo sapiens)
Explore Q8IW75 
Go to UniProtKB:  Q8IW75
NIH Common Fund Data Resources
PHAROS:  Q8IW75
GTEx:  ENSG00000165953
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4
Download Ideal Coordinates CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L		 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.08 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.197 
  • R-Value Observed: 0.197 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 133.55α = 90
b = 152.1β = 97.52
c = 61.45γ = 90
Software Package:
Software NamePurpose
PHASERphasing
BUSTERrefinement
XDSdata reduction
XSCALEdata scaling

Structure Validation

View Full Validation Report


View more in-depth experimental data

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2013-02-13
    Type: Initial release
  • Version 1.1: 2013-07-31
    Changes: Database references