title: Degradation of rRNA in BM-N cells from the silkworm Bombyx mori during abortive infection with heterologous nucleopolyhedroviruses.
abstract: Cell lines derived from the silkworm, Bombyx mori, are only permissive for B. mori nucleopolyhedrovirus (NPV), with other NPVs generally resulting in abortive infection. Here, we demonstrate that rRNA of B. mori BM-N cells undergoes rapid degradation through site-specific cleavage upon infection with NPVs from Autographa californica (AcMNPV), Hyphantria cunea (HycuMNPV), Spodoptera exigua (SeMNPV) and Spodoptera litura (SpltMNPV). No significant decreases in cellular RNA were observed in Ld652Y, Se301, Sf9, SpIm and S2 cells infected with AcMNPV or HycuMNPV, indicating the response is unique to BM-N cells. A transient expression assay using a cosmid library of the HycuMNPV genome demonstrated that HycuMNPV P143 is responsible for rRNA degradation, which was also detected in BM-N cells transfected with plasmids expressing the P143 proteins from AcMNPV, SeMNPV and SpltMNPV. These results indicate that B. mori evolved to acquire a unique antiviral immune mechanism that is activated by P143 proteins from heterologous NPVs.
authors.affiliation: Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Rina
authors.initials: R
authors.lastname: Hamajima
authors.affiliation: Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Haruka
authors.initials: H
authors.lastname: Ichikawa
authors.affiliation: United Graduate School of Agricultural Sciences, Tottori University, Koyama-cho, Minami 4-101, Tottori 680-8553, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mitsutake
authors.affiliation: Faculty of Agriculture, Yamaguchi University, Yoshida 1677-1, Yamaguchi 753-8515, Japan.|United Graduate School of Agricultural Sciences, Tottori University, Koyama-cho, Minami 4-101, Tottori 680-8553, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kobayashi
authors.affiliation: Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Laboratory of Sericulture and Entomoresources, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
authors.forename: Motoko
authors.initials: M
authors.lastname: Ikeda
mesh_terms: D000818:Animals; D002460:Cell Line; D007915:Lepidoptera / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000254:growth & development*; D020871:RNA Stability; D012335:RNA, Ribosomal / Q000378:metabolism*
chemical_list: D012335:RNA, Ribosomal