1ZBX

Crystal structure of a Orc1p-Sir1p complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.220 
  • R-Value Observed: 0.220 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structural basis for origin recognition complex 1 protein-silence information regulator 1 protein interaction in epigenetic silencing

Hsu, H.C.Stillman, B.Xu, R.M.

(2005) Proc Natl Acad Sci U S A 102: 8519-8524

  • DOI: 10.1073/pnas.0502946102
  • Primary Citation of Related Structures:  
    1ZBX

  • PubMed Abstract: 
  • The interaction between silence information regulator 1 protein (Sir1p) and origin recognition complex 1 protein (Orc1p), the largest subunit of the origin recognition complex, plays an important role in the establishment of transcriptional silencing at the cryptic mating-type gene loci in Saccharomyces cerevisiae ...

    The interaction between silence information regulator 1 protein (Sir1p) and origin recognition complex 1 protein (Orc1p), the largest subunit of the origin recognition complex, plays an important role in the establishment of transcriptional silencing at the cryptic mating-type gene loci in Saccharomyces cerevisiae. Sir1p binds the N-terminal region of Orc1p encompassing a Bromo-adjacent homology (BAH) domain found in various chromatin-associated proteins. To understand the molecular mechanism of Sir protein recruitment, we have determined a 2.5-A cocrystal structure of the N-terminal domain of Orc1p in complex with the Orc1p-interacting domain of Sir1p. The structure reveals that Sir1p Orc1p-interacting domain has a bilobal structure: an alpha/beta N-terminal lobe and a C-terminal lobe resembling the Tudor domain royal family fold. The N-terminal lobe of Sir1p binds in a shallow groove between a helical subdomain and the BAH domain of Orc1p. The structure provides a mechanistic understanding of Orc1p-Sir1p interaction specificity, as well as insights into protein-protein interactions involving BAH domains in general.


    Organizational Affiliation

    Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Origin recognition complex subunit 1A219Saccharomyces cerevisiaeMutation(s): 0 
Gene Names: ORC1
UniProt
Find proteins for P54784 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P54784 
Go to UniProtKB:  P54784
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP54784
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Regulatory protein SIR1B140Saccharomyces cerevisiaeMutation(s): 0 
Gene Names: SIR1
UniProt
Find proteins for P21691 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P21691 
Go to UniProtKB:  P21691
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP21691
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.260 
  • R-Value Work: 0.220 
  • R-Value Observed: 0.220 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 70α = 90
b = 137.21β = 90
c = 139.77γ = 90
Software Package:
Software NamePurpose
MADNESSdata collection
SCALEPACKdata scaling
PHASESphasing
CNSrefinement
MADNESSdata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2005-06-21
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-10-11
    Changes: Refinement description