3OZQ

Crystal structure of Serpin48, which is a highly specific serpin in the insect Tenebrio molitor


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.221 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural and functional characterization of a highly specific serpin in the insect innate immunity

Park, S.H.Jiang, R.Piao, S.Zhang, B.Kim, E.H.Kwon, H.M.Jin, X.L.Lee, B.L.Ha, N.-C.

(2011) J.Biol.Chem. 286: 1567-1575

  • DOI: 10.1074/jbc.M110.144006

  • PubMed Abstract: 
  • The Toll signaling pathway, an essential innate immune response in invertebrates, is mediated via the serine protease cascade. Once activated, the serine proteases are irreversibly inactivated by serine protease inhibitors (serpins). Recently, we ide ...

    The Toll signaling pathway, an essential innate immune response in invertebrates, is mediated via the serine protease cascade. Once activated, the serine proteases are irreversibly inactivated by serine protease inhibitors (serpins). Recently, we identified three serpin-serine protease pairs that are directly involved in the regulation of Toll signaling cascade in a large beetle, Tenebrio molitor. Of these, the serpin SPN48 was cleaved by its target serine protease, Spätzle-processing enzyme, at a noncanonical P1 residue of the serpin's reactive center loop. To address this unique cleavage, we report the crystal structure of SPN48, revealing that SPN48 exhibits a native conformation of human antithrombin, where the reactive center loop is partially inserted into the center of the largest β-sheet of SPN48. The crystal structure also shows that SPN48 has a putative heparin-binding site that is distinct from those of the mammalian serpins. Ensuing biochemical studies demonstrate that heparin accelerates the inhibition of Spätzle-processing enzyme by a proximity effect in targeting the SPN48. Our finding provides the molecular mechanism of how serpins tightly regulate innate immune responses in invertebrates.


    Organizational Affiliation

    College of Pharmacy and Research Institute for Drug Development, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Republic of Korea.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Serpin48
A
376Tenebrio molitorMutation(s): 0 
Gene Names: SPN48
Find proteins for D1MYQ6 (Tenebrio molitor)
Go to UniProtKB:  D1MYQ6
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.279 
  • R-Value Work: 0.221 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 66.061α = 90.00
b = 42.561β = 105.16
c = 66.178γ = 90.00
Software Package:
Software NamePurpose
ADSCdata collection
PHENIXmodel building
HKL-2000data scaling
PHENIXrefinement
HKL-2000data reduction
PHENIXphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-10-27
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2013-10-09
    Type: Database references