1TKV

Solution Structure of T4 AsiA Dimer


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 23 
  • Selection Criteria: structures with acceptable covalent geometry,structures with the least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Flipping a genetic switch by subunit exchange

Lambert, L.J.Schirf, V.Demeler, B.Cadene, M.Werner, M.H.

(2001) Embo J. 20: 7149-7159

  • DOI: 10.1093/emboj/20.24.7149
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The bacteriophage T4 AsiA protein is a multifunctional protein that simultaneously acts as both a repressor and activator of gene expression during the phage life cycle. These dual roles with opposing transcriptional consequences are achieved by modi ...

    The bacteriophage T4 AsiA protein is a multifunctional protein that simultaneously acts as both a repressor and activator of gene expression during the phage life cycle. These dual roles with opposing transcriptional consequences are achieved by modification of the host RNA polymerase in which AsiA binds to conserved region 4 (SR4) of sigma(70), altering the pathway of promoter selection by the holoenzyme. The mechanism by which AsiA flips this genetic switch has now been revealed, in part, from the three-dimensional structure of AsiA and the elucidation of its interaction with SR4. The structure of AsiA is that of a novel homodimer in which each monomer is constructed as a seven-helix bundle arranged in four overlapping helix-loop-helix elements. Identification of the protein interfaces for both the AsiA homodimer and the AsiA-sigma(70) complex reveals that these interfaces are coincident. Thus, the AsiA interaction with sigma(70) necessitates that the AsiA homodimer dissociate to form an AsiA-SR4 heterodimer, exchanging one protein subunit for another to alter promoter choice by RNA polymerase.


    Organizational Affiliation

    Laboratory of Molecular Biophysics, The Rockefeller University, 1230 York Avenue, Box 42, New York, NY 10021, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
10 kDa anti-sigma factor
A, B
90Enterobacteria phage T4Mutation(s): 0 
Gene Names: asiA
Find proteins for P32267 (Enterobacteria phage T4)
Go to UniProtKB:  P32267
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 23 
  • Selection Criteria: structures with acceptable covalent geometry,structures with the least restraint violations 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-06-22
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance