Involvement of phage phi 29 DNA polymerase and terminal protein subdomains in conferring specificity during initiation of protein-primed DNA replication

To initiate phi 29 DNA replication, the DNA polymerase has to form a complex with the homologous primer terminal protein (TP) that further recognizes the replication origins of the homologous TP-DNA placed at both ends of the linear genome. By means of chimerical proteins, constructed by swapping th...

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Detalles Bibliográficos
Autores: Pérez-Arnáiz, Patricia, Longás, Elisa, Villar, Laurentino, Lázaro, José M., Salas, Margarita, Vega, Miguel de
Tipo de recurso: artículo
Fecha de publicación:2007
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/7901
Acceso en línea:http://hdl.handle.net/10261/7901
Access Level:acceso abierto
Palabra clave:Phi 29 DNA polymerase
Phi 29 TP-DNA
Descripción
Sumario:To initiate phi 29 DNA replication, the DNA polymerase has to form a complex with the homologous primer terminal protein (TP) that further recognizes the replication origins of the homologous TP-DNA placed at both ends of the linear genome. By means of chimerical proteins, constructed by swapping the priming domain of the related phi 29 and GA-1 TPs, we show that DNA polymerase can form catalytically active heterodimers exclusively with that chimerical TP containing the N-terminal part of the homologous TP, suggesting that the interaction between the polymerase TPR-1 subdomain and the TP N-terminal part is the one mainly responsible for the specificity between both proteins. We also show that the TP N-terminal part assists the proper binding of the priming domain at the polymerase active site. Additionally, a chimerical phi 29 DNA polymerase containing the GA-1 TPR-1 subdomain could use GA-1 TP, but only in the presence of phi 29 TP-DNA as template, indicating that parental TP recognition is mainly accomplished by the DNA polymerase. The sequential events occurring during initiation of bacteriophage protein-primed DNA replication are proposed