Flexible tethering of primase and DNA Pol α in the eukaryotic primosome.

ABSTRACT: The Pol α/primase complex or primosome is the primase/polymerase complex that initiates nucleic acid synthesis during eukaryotic replication. Within the primosome, the primase synthesizes short RNA primers that undergo limited extension by Pol α. The resulting RNA-DNA primers are utilized by Pol δ and Pol ε for processive elongation on the lagging and leading strands, respectively. Despite its importance, the mechanism of RNA-DNA primer synthesis remains poorly understood. Here, we describe a structural model of the yeast primosome based on electron microscopy and functional studies. The 3D architecture of the primosome reveals an asymmetric, dumbbell-shaped particle. The catalytic centers of primase and Pol α reside in separate lobes of high relative mobility. The flexible tethering of th

SUBMITTER: Nunez-Ramirez R 

PROVIDER: S-EPMC3185431 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature