ABSTRACT
The interplay between the host and Human cytomegalovirus (HCMV) plays a pivotal role in the outcome of an infection. HCMV growth in endothelial and epithelial cells requires expression of viral proteins UL128, UL130, and UL131 proteins (UL128-131), of which UL130 is the largest gene and the only one that is not interrupted by introns.Mutation of the C terminus of the UL130 protein causes reduced tropism of endothelial cells (EC). However, very few host factors have been identified that interact with the UL130 protein. In this study, HCMV UL130 protein was shown to directly interact with the human protein Snapin in human embryonic kidney HEK293 cells by Yeast two-hybrid screening, in vitro glutathione S-transferase (GST) pull-down, and co-immunoprecipitation. Additionally, heterologous expression of protein UL130 revealed co-localization with Snapin in the cell membrane and cytoplasm of HEK293 cells using fluorescence confocal microscopy. Furthermore, decreasing the level of Snapin via specific small interfering RNAs decreased the number of viral DNA copies and titer inHCMV-infected U373-S cells. Taken together, these results suggest that Snapin, the pUL130 interacting protein, has a role in modulating HCMV DNA synthesis.
ABSTRACT
Objective To screen the human proteins interacting with human cytomegalovirus（HCMV）UL130 from human fetus brain cDNA library by GAL4 two-hybrid system 3 technique and analyze the corresponding coding sequences.Methods The ＂bait plasmid＂（named as pGBKT7-UL130）was constructed.By using HCMV UL130 as the bait,a human fetus brain cDNA library was screened and the proteins interacting with UL130 protein were searched.The positive clones were sequenced and analyzed by bioinformatic methods.Results Nine clones interacting with HCMV UL130 were identified,two of them were synaptosome-associated protein（SNAP）.Conclusion Some proteins interacting with HCMV UL130 in human fetus brain cDNA library were successfully screened.SNAP might play an important role in HCMV infection pathogenesis.