|
|||||
|
|
3D architecture of DNA Pol α reveals the functional core of multi-subunit replicative polymerases |
||
| Authors: | Sebastian Klinge, Rafael Nú ez-Ramí rez, Oscar Llorca, Luca Pellegrini | |
| Affiliation: | Sebastian Klinge, Rafael Núñez-Ramírez, Oscar Llorca, and Luca Pellegrini | |
| Abstract: | Eukaryotic DNA replication requires the coordinated activity of the multi-subunit DNA polymerases: Pol α, Pol δ and Pol ![[var epsilon]](corehtml/pmc/pmcents/epsiv.gif "/>. The conserved catalytic and regulatory B subunits associate in a constitutive heterodimer that represents the functional core of all three replicative polymerases. Here, we combine X-ray crystallography and electron microscopy (EM) to describe subunit interaction and 3D architecture of heterodimeric yeast Pol α. The crystal structure of the C-terminal domain (CTD) of the catalytic subunit bound to the B subunit illustrates a conserved mechanism of accessory factor recruitment by replicative polymerases. The EM reconstructions of Pol α reveal a bilobal shape with separate catalytic and regulatory modules. Docking of the B–CTD complex in the EM reconstruction shows that the B subunit is tethered to the polymerase domain through a structured but flexible linker. Our combined findings provide a structural template for the common functional architecture of the three major replicative DNA polymerases.</td>
</tr>
<tr>
<td align="){kind=small} | |
| Keywords: | DNA polymerase α DNA replication electron microscopy X‐ray crystallography | |