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Domain structures and inter-domain interactions defining the holoenzyme architecture of archaeal d-family DNA polymerase.

ABSTRACT: Archaea-specific D-family DNA polymerase (PolD) forms a dimeric heterodimer consisting of two large polymerase subunits and two small exonuclease subunits. According to the protein-protein interactions identified among the domains of large and small subunits of PolD, a symmetrical model for the domain topology of the PolD holoenzyme is proposed. The experimental evidence supports various aspects of the model. The conserved amphipathic nature of the N-terminal putative ?-helix of the large subunit plays a key role in the homodimeric assembly and the self-cyclization of the large subunit and is deeply involved in the archaeal PolD stability and activity. We also discuss the evolutional transformation from archaeal D-family to eukaryotic B-family polymerase on the basis of the structural information.

SUBMITTER: Matsui I

PROVIDER: S-EPMC4187176 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Domain structures and inter-domain interactions defining the holoenzyme architecture of archaeal d-family DNA polymerase.

Matsui Ikuo I Matsui Eriko E Yamasaki Kazuhiko K Yokoyama Hideshi H

Life (Basel, Switzerland) 20130705 3

Archaea-specific D-family DNA polymerase (PolD) forms a dimeric heterodimer consisting of two large polymerase subunits and two small exonuclease subunits. According to the protein-protein interactions identified among the domains of large and small subunits of PolD, a symmetrical model for the domain topology of the PolD holoenzyme is proposed. The experimental evidence supports various aspects of the model. The conserved amphipathic nature of the N-terminal putative α-helix of the large subuni ...[more]

PMID: 25369811

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