the chromatin remodeling factor smarcb1 forms a complex with human cytomegalovirus proteins ul114 and ul44染色质重塑因子smarcb1形成一个复杂的人类巨细胞病毒蛋白质ul114和ul44.pdf

The Chromatin Remodeling Factor SMARCB1 Forms a Complex with Human Cytomegalovirus Proteins UL114 and UL44 Toril Ranneberg-Nilsen1,3, Halvor Rollag 1, Ragnhild Slettebakk 1, Paul Hoff Backe 1,2,3, Øyvind Olsen 1,2,3, 1,3 ˚ 1,2,3 Luisa Luna , Magnar Bjøras * 1 Department of Microbiology, University of Oslo and Oslo University Hospital HF, Rikshospitalet, Oslo, Norway, 2 Department of Medical Biochemistry, University of Oslo and Oslo University Hospital HF, Rikshospitalet, Oslo, Norway, 3 Centre for Molecular Biology and Neuroscience, University of Oslo and Oslo University Hospital HF, Rikshospitalet, Oslo, Norway Abstract Background: Human cytomegalovirus (HCMV) uracil DNA glycosylase, UL114, is required for efficient viral DNA replication. Presumably, UL114 functions as a structural partner to other factors of the DNA-replication machinery and not as a DNA repair protein. UL114 binds UL44 (HCMV processivity factor) and UL54 (HCMV-DNA-polymerase). In the present study we have searched for cellular partners of UL114. Methodology/Principal Findings: In a yeast two-hybrid screen SMARCB1, a factor of the SWI/SNF chromatin remodeling complex, was found to be an interacting partner of UL114. This interaction was confirmed in vitro by co- immunoprecipitation and pull-down. Immunofluorescence microscopy revealed that SMARCB1 along with BRG-1, BAF170 and BAF155, which are the core SWI/SNF components required for efficient chromatin remodeling, were present in virus replication foci 24–48 hours post infection (hpi). Furthermore a direct interaction was also demonstrated for SMARCB1 and UL44. Conclusions/Significance: The core SWI/SNF factors required for efficient chromatin remodeling are present in the HCM