Domain topology of the DNA polymerase D complex from a hyperthermophilic archaeon Pyrococcus horikoshii.
Family D DNA polymerase (PolD) is a recently found DNA polymerase extensively existing in Euryarchaeota of Archaea. Here, we report the domain function of PolD in oligomerization and interaction with other proteins, which were characterized with the yeast two-hybrid (Y2H) and surface plasmon resonance (SPR) assays. A proliferating cell nuclear antigen, PhoPCNA, interacted with the N-terminus of the small subunit, DP1(1-200). Specific interaction between the remaining part of the small subunit, DP1(201-622), and the N-terminus of the large subunit, DP2(1-300), was detected by the Y2H assay. The SPR assay also indicated the intrasubunit interaction within the N-terminus, DP2(1-100), and the C-terminus, DP2(792-1163), of the large subunit. A synthetic 21 amino acid peptide corresponding to the sequence from cysteine cluster II, DP2(1290-1310), tightly interacted (a dissociation constant K(D) = 4.3 nM) with the N-terminus of the small subunit, DP1(1-200). Since the peptide could increase the 3'-5' exonuclease activity of DP1 [Shen et al. (2004) Nucleic Acids Res. 32, 158], the short region DP2(1290-1310) seems to play dual roles to form the PhoPolD complex and to regulate the 3'-5' exonuclease activity of DP1 through interaction with DP1(1-200). Furthermore, DP2(792-1163) containing the catalytic residues for DNA polymerization, Asp1122 and Asp1124, interacted with the intrasubunit domain, DP2(1-100), and the intersubunit domain, DP1(1-200). DP2(792-1163) probably forms the most important domain deeply involved in both the catalysis of DNA polymerization and stabilization of the PhoPolD complex through these multiple interactions.
Tang
Xiao-Feng
XF
Biological Information Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8566, Japan.
Shen
Yulong
Y
Matsui
Eriko
E
Matsui
Ikuo
I
D000255:Adenosine Triphosphate / Q000378:metabolism; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009097:Multienzyme Complexes; D017434:Protein Structure, Tertiary; D043902:Pyrococcus horikoshii / Q000201:enzymology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques
D019843:Archaeal Proteins; D009097:Multienzyme Complexes; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D004259:DNA-Directed DNA Polymerase