Recruitment of DNA replication and damage response proteins to viral replication centers during infection with NS2 mutants of Minute Virus of Mice (MVM)

• Published in: Virology (New York, N.Y.) Vol. 410; no. 2; pp. 375 - 384
• Main Authors: Ruiz, Zandra, Mihaylov, Ivailo S., Cotmore, Susan F., Tattersall, Peter
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 20.02.2011
• Subjects: Animals; Cell Line; DNA; DNA damage; DNA damage responses; DNA Repair; DNA Replication; DNA, Viral - genetics; DNA, Viral - metabolism; gene expression regulation; Host-Pathogen Interactions; Infectious Disease; mechanism of action; Mice; Minute virus of mice; Minute Virus of Mice (MVM); Minute Virus of Mice - genetics; Minute Virus of Mice - physiology; mutants; Parvovirus; phosphorylation; Proteins - metabolism; Rodent protoparvovirus 1; Viral Nonstructural Proteins - deficiency; viral proteins; Viral replication centers; Virus Replication; Minute Virus of Mice (MVM); Parvovirus; DNA damage responses; Viral replication centers
• ISSN: 0042-6822; 1096-0341; 1096-0341
• DOI: 10.1016/j.virol.2010.12.009

MVM NS2 is essential for viral DNA amplification, but its mechanism of action is unknown. A classification scheme for autonomous parvovirus-associated replication (APAR) center development, based on NS1 distribution, was used to characterize abnormal APAR body maturation in NS2null mutant infections, and their organization examined for defects in host protein recruitment. Since acquisition of known replication factors appeared normal, we looked for differences in invoked DNA damage responses. We observed widespread association of H2AX/MDC1 damage response foci with viral replication centers, and sequestration and complex hyperphosphorylation of RPA 32, which occurred in wildtype and mutant infections. Quantifying these responses by western transfer indicated that both wildtype and NS2 mutant MVM elicited ATM activation, while phosphorylation of ATR, already basally activated in asynchronous A9 cells, was downregulated. We conclude that MVM infection invokes multiple damage responses that influence the APAR environment, but that NS2 does not modify the recruitment of cellular proteins.