1N25

Crystal structure of the SV40 Large T antigen helicase domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.243 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the replicative helicase of the oncoprotein SV40 large tumour antigen

Li, D.Zhao, R.Lilyestrom, W.Gai, D.Zhang, R.DeCaprio, J.A.Fanning, E.Jochimiak, A.Szakonyi, G.Chen, X.S.

(2003) Nature 423: 512-518

  • DOI: 10.1038/nature01691

  • PubMed Abstract: 
  • The oncoprotein large tumour antigen (LTag) is encoded by the DNA tumour virus simian virus 40. LTag transforms cells and induces tumours in animals by altering the functions of tumour suppressors (including pRB and p53) and other key cellular protei ...

    The oncoprotein large tumour antigen (LTag) is encoded by the DNA tumour virus simian virus 40. LTag transforms cells and induces tumours in animals by altering the functions of tumour suppressors (including pRB and p53) and other key cellular proteins. LTag is also a molecular machine that distorts/melts the replication origin of the viral genome and unwinds duplex DNA. LTag therefore seems to be a functional homologue of the eukaryotic minichromosome maintenance (MCM) complex. Here we present the X-ray structure of a hexameric LTag with DNA helicase activity. The structure identifies the p53-binding surface and reveals the structural basis of hexamerization. The hexamer contains a long, positively charged channel with an unusually large central chamber that binds both single-stranded and double-stranded DNA. The hexamer organizes into two tiers that can potentially rotate relative to each other through connecting alpha-helices to expand/constrict the channel, producing an 'iris' effect that could be used for distorting or melting the origin and unwinding DNA at the replication fork.


    Organizational Affiliation

    Department of Biochemistry and Molecular Genetics, University of Colorado Health Science Center, School of Medicine, Denver, Colorado 80262, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Large T Antigen
A, B
368Simian virus 40EC: 3.6.4.-
Find proteins for P03070 (Simian virus 40)
Go to UniProtKB:  P03070
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A, B
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.276 
  • R-Value Work: 0.243 
  • Space Group: P 3 2 1
Unit Cell:
Length (Å)Angle (°)
a = 120.321α = 90.00
b = 120.321β = 90.00
c = 132.202γ = 120.00
Software Package:
Software NamePurpose
HKL-2000data reduction
SOLVEphasing
TRUNCATEdata reduction
CCP4data scaling
HKL-2000data collection
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-06-03
    Type: Initial release
  • Version 1.1: 2008-04-28
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance