Degradation of rRNA in BM-N cells from the silkworm Bombyx mori during abortive infection with heterologous nucleopolyhedroviruses

作者：Hamajima Rina; Ito Yuya; Ichikawa Haruka; Mitsutake Hiroshi; Kobayashi Jun; Kobayashi Michihiro; Ikeda Motoko^*

来源：Journal of General Virology, 2013, 94(Pt_9): 2102-2111.

DOI：10.1099/vir.0.053645-0

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, Splm 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.

• 出版日期2013-9