title: Biochemical evidence of a physical interaction between Sulfolobus solfataricus B-family and Y-family DNA polymerases.
abstract: The hyper-thermophilic archaeon Sulfolobus solfataricus possesses two functional DNA polymerases belonging to the B-family (Sso DNA pol B1) and to the Y-family (Sso DNA pol Y1). Sso DNA pol B1 recognizes the presence of uracil and hypoxanthine in the template strand and stalls synthesis 3-4 bases upstream of this lesion ("read-ahead" function). On the other hand, Sso DNA pol Y1 is able to synthesize across these and other lesions on the template strand. Herein we report evidence that Sso DNA pol B1 physically interacts with DNA pol Y1 by surface plasmon resonance measurements and immuno-precipitation experiments. The region of DNA pol B1 responsible for this interaction has been mapped in the central portion of the polypeptide chain (from the amino acid residue 482 to 617), which includes an extended protease hyper-sensitive linker between the N- and C-terminal modules (amino acid residues Asn482-Ala497) and the alpha-helices forming the "fingers" sub-domain (alpha-helices R, R' and S). These results have important implications for understanding the polymerase-switching mechanism on the damaged template strand during genome replication in S. solfataricus.
authors.affiliation: Istituto di Biochimica delle Proteine, Consiglio Nazionale delle Ricerche, Via P. Castellino. 111, 80131, Napoli, Italy.
authors.forename: Mariarita
authors.initials: M
authors.lastname: De Felice
authors.forename: Barbara
authors.initials: B
authors.lastname: Medagli
authors.forename: Luca
authors.initials: L
authors.lastname: Esposito
authors.forename: Mariarosaria
authors.initials: M
authors.lastname: De Falco
authors.forename: Biagio
authors.initials: B
authors.lastname: Pucci
authors.forename: Mosè
authors.initials: M
authors.lastname: Rossi
authors.forename: Petr
authors.initials: P
authors.lastname: Grùz
authors.forename: Takehiko
authors.initials: T
authors.lastname: Nohmi
authors.forename: Francesca M
authors.initials: FM
authors.lastname: Pisani
mesh_terms: D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism*; D004249:DNA Damage; D004261:DNA Replication / Q000502:physiology*; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000378:metabolism*; D020745:Genome, Archaeal / Q000502:physiology*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D048229:Sulfolobus solfataricus / Q000201:enzymology*; D020349:Surface Plasmon Resonance
chemical_list: D019843:Archaeal Proteins; C436950:Dbh protein, Sulfolobus solfataricus; D004259:DNA-Directed DNA Polymerase