1IG9: Structure Of The Replicating Complex Of A Pol Alpha Family Dna Polymerase

We describe the 2.6 A resolution crystal structure of RB69 DNA polymerase with primer-template DNA and dTTP, capturing the step just before primer extension. This ternary complex structure in the human DNA polymerase alpha family shows a 60 degrees rotation of the fingers domain relative to the apo-protein structure, similar to the fingers movement in pol I family polymerases. Minor groove interactions near the primer 3' terminus suggest a common fidelity mechanism for pol I and pol alpha family polymerases. The duplex product DNA orientation differs by 40 degrees between the polymerizing mode and editing mode structures. The role of the thumb in this DNA motion provides a model for editing in the pol alpha family.
PDB ID: 1IG9Download
MMDB ID: 106020
PDB Deposition Date: 2001/4/17
Updated in MMDB: 2012/12
Experimental Method:
x-ray diffraction
Resolution: 2.6  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 1IG9: trimeric; determined by author
Molecular Components in 1IG9
Label Count Molecule
Protein (1 molecule)
DNA Polymerase(Gene symbol: 43)
Molecule annotation
Nucleotides(2 molecules)
5'- D(*ap*cp*ap*gp*gp*tp*ap*ap*gp*cp*ap*gp*tp*cp*cp*gp*cp*g)- 3'
Molecule annotation
5'- D(*gp*cp*gp*gp*ap*cp*tp*gp*cp*tp*tp*ap*cp*(doc))-3'
Molecule annotation
Chemicals (5 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB