The DEAD/H-box helicase DHX9 contributes to suppression of Bombyx mori nucleopolyhedrovirus propagation in B. mori cells.

Antiviral immune responses are mainly triggered through the recognition of virus-derived nucleic acids by host-specific pattern recognition receptors (PRRs). Here, we identified and characterized homologs of human PRRs for virus-derived DNA in Bombyx mori upon infection with a nucleopolyhedrovirus (NPV), a member of the family Baculoviridae. We found that progeny virus production of B.

NISES-AnPe-428 cell line derived from the Chinese oak silkworm is permissive for multiple nucleopolyhedrovirus species from insects of four different families.

The cell line NISES-AnPe-428 (AnPe), derived from the Chinese oak silkworm , was characterized for its permissiveness and productivity for six different nucleopolyhedrovirus (NPV) species. These NPVs included homologous Antheraea pernyi NPV (AnpeNPV) and heterologous Autographa californica multiple NPV (AcMNPV), Bombyx mori NPV (BmNPV), Hyphantria cunea MNPV (HycuMNPV), Spodoptera exigua MNPV (SeMNPV), and Lymantria dispar MNPV (LdMNPV), representing viruses that had been isolated from insect species belonging to five different families (, , , , and ). We found that AnPe cells supported productive replication of AnpeNPV, AcMNPV, BmNPV, HycuMNPV, and SeMNPV to varying degrees.

Identification of the minimal AcMNPV P143 protein region responsible for triggering apoptosis and rRNA degradation of Bombyx mori cells.

Bombyx mori cells induce antiviral responses including global protein synthesis shutdown, rRNA degradation, and apoptosis upon infection with Autographa californica multiple nucleopolyhedrovirus (AcMNPV). We previously demonstrated that five and six amino acid residues located at positions between 514 and 599 of AcMNPV P143 (Ac-P143) protein are important for induction of apoptosis and rRNA degradation, respectively. However, it remains unexplored whether other residues of Ac-P143 protein also participate in antiviral immune responses.

Novel genes participating in the formation of prismatic and nacreous layers in the pearl oyster as revealed by their tissue distribution and RNA interference knockdown.

In our previous publication, we identified novel gene candidates involved in shell formation by EST analyses of the nacreous and prismatic layer-forming tissues in the pearl oyster Pinctada fucata. In the present study, 14 of those genes, including two known genes, were selected and further examined for their involvement in shell formation using the RNA interference. Molecular characterization based on the deduced amino acid sequences showed that seven of the novel genes encode secretory proteins.