Subcellular localization of Bombyx mori ribosomal protein S3a and effect of its over-expression on BmNPV infection

Abstract

In the present study, using a BV/PH-Bms3a-EGFP, we found that Bombyx mori ribosomal protein S3a (BmS3a) with EGFP fused to its C-terminal, was predominantly localized in the cytoplasm of B. mori cells. Subsequently, to investigate the effect of BmS3a over-expression on BmNPV infection both at the cellular level and in vivo, a transgenic BmN cell line expressing BmS3a was constructed using a piggybac-A3-EGFP and recombinant baculovirues expressing BmS3a-EGFP fusion protein (BV/IE1-Bms3a-EGFP) or EGFP (BV/EGFP) were produced using BmNPV/Bac-to-Bac expression system. Results showed that the number of polyhedral in the transgenic cells of BmS3a was much smaller than that in non-transgenic cells, and that silkworms injected with BV/IE1-Bms3a-EGFP survived much longer than those injected with BV/EGFP. Taken together, we speculated that BmS3a might be capable of inhibiting BmNPV replication through its activities in the cytoplasm.