5MZ6

Cryo-EM structure of a Separase-Securin complex from Caenorhabditis elegans at 3.8 A resolution


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.8 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Cryo-EM structure of a metazoan separase-securin complex at near-atomic resolution.

Boland, A.Martin, T.G.Zhang, Z.Yang, J.Bai, X.C.Chang, L.Scheres, S.H.Barford, D.

(2017) Nat. Struct. Mol. Biol. 24: 414-418

  • DOI: 10.1038/nsmb.3386

  • PubMed Abstract: 
  • Separase is a caspase-family protease that initiates chromatid segregation by cleaving the kleisin subunits (Scc1 and Rec8) of cohesin, and regulates centrosome duplication and mitotic spindle function through cleavage of kendrin and Slk19. To unders ...

    Separase is a caspase-family protease that initiates chromatid segregation by cleaving the kleisin subunits (Scc1 and Rec8) of cohesin, and regulates centrosome duplication and mitotic spindle function through cleavage of kendrin and Slk19. To understand the mechanisms of securin regulation of separase, we used single-particle cryo-electron microscopy (cryo-EM) to determine a near-atomic-resolution structure of the Caenorhabditis elegans separase-securin complex. Separase adopts a triangular-shaped bilobal architecture comprising an N-terminal tetratricopeptide repeat (TPR)-like α-solenoid domain docked onto the conserved C-terminal protease domain. Securin engages separase in an extended antiparallel conformation, interacting with both lobes. It inhibits separase by interacting with the catalytic site through a pseudosubstrate mechanism, thus revealing that in the inhibited separase-securin complex, the catalytic site adopts a conformation compatible with substrate binding. Securin is protected from cleavage because an aliphatic side chain at the P1 position represses protease activity by disrupting the organization of catalytic site residues.


    Organizational Affiliation

    MRC Laboratory of Molecular Biology, Cambridge, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SEParase
1
1262Caenorhabditis elegansMutation(s): 0 
Gene Names: sep-1
EC: 3.4.22.49
Find proteins for G5ED39 (Caenorhabditis elegans)
Go to UniProtKB:  G5ED39
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Interactor of FizzY protein
B
244Caenorhabditis elegansMutation(s): 0 
Gene Names: ify-1
Find proteins for Q18235 (Caenorhabditis elegans)
Go to UniProtKB:  Q18235
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.8 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
Software Package:
Software NamePurpose
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2017-03-08
    Type: Initial release
  • Version 1.1: 2017-03-15
    Type: Database references
  • Version 1.2: 2017-04-19
    Type: Database references
  • Version 1.3: 2017-08-30
    Type: Data collection
  • Version 1.4: 2019-12-11
    Type: Other