Adenosine Receptor Modulates Permissiveness of Baculovirus (Budded Virus) Infection via Regulation of Energy Metabolism in Bombyx mori

Bombyx mori nucleopolyhedrovirus ORF56 (Bm56) is a baculovirus core gene that is highly conserved in all baculoviruses that have had their genomes sequenced to date. Its transcripts in BmNPV-infected cells could be detected from 12 h post-infection (p.i.) and the encoded protein could be detected at 16 h p.i. by using a polyclonal antibody against glutathione S-transferase–Bm56 fusion protein. Western blot analysis showed that Bm56 is a structural component of the occlusion-derived virus nucleocapsid. Subsequent confocal microscopy revealed that Bm56 was distributed in the outer nuclear membrane and the intranuclear region of infected cells. To investigate the role of Bm56 in virus replication, a Bm56-knockout bacmid of BmNPV was constructed via homologous recombination in Escherichia coli. The Bm56 deletion had no effect on budded virus (BV) production in cultured cells; however, the deletion affected occlusion-body morphogenesis. A larval bioassay demonstrated that the Bm56 deletion did not reduce infectivity, whereas it resulted in a 50 % lethal time that was 16–18 h longer than that of the wild-type bacmid at every dose used in this study. These results indicate that Bm56 facilitates efficient virus production in vivo; however, it is not essential for BV production in vitro.

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Characterization of Bombyx mori Nucleopolyhedrovirus orf68 Gene That Encodes a Novel Structural Protein of Budded Virus

Virology ◽

10.1006/viro.2002.1443 ◽

2002 ◽

Vol 297 (1) ◽

pp. 39-47 ◽

Cited By ~ 19

Author(s):

Masashi Iwanaga ◽

Masaaki Kurihara ◽

Masahiko Kobayashi ◽

WonKyung Kang

Keyword(s):

Bombyx Mori ◽

Structural Protein ◽

Bombyx Mori Nucleopolyhedrovirus ◽

Budded Virus

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Effects of a virus infection on the protein synthesis in the silk gland of Bombyx mori

Journal of Invertebrate Pathology ◽

10.1016/0022-2011(69)90016-0 ◽

1969 ◽

Vol 14 (1) ◽

pp. 102-103 ◽

Cited By ~ 5

Author(s):

Hitoshi Watanabe ◽

Masahiko Kobayashi

Keyword(s):

Protein Synthesis ◽

Virus Infection ◽

Bombyx Mori ◽

Silk Gland

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cDNA cloning and characterization of LASP1 from silkworm, Bombyx mori, involved in cytoplasmic polyhedrosis virus infection

Gene ◽

10.1016/j.gene.2012.09.062 ◽

2012 ◽

Vol 511 (2) ◽

pp. 389-397 ◽

Cited By ~ 4

Author(s):

Kun Gao ◽

Xiang-yuan Deng ◽

He-ying Qian ◽

Ping Wu ◽

Guang-xing Qin ◽

...

Keyword(s):

Virus Infection ◽

Bombyx Mori ◽

Cdna Cloning ◽

Cytoplasmic Polyhedrosis Virus ◽

Polyhedrosis Virus ◽

Silkworm Bombyx Mori

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Impact of honey-enriched mulberry diet on the energy metabolism of the silkworm, Bombyx mori

Journal of Applied and Natural Science ◽

10.31018/jans.vi.2273 ◽

2020 ◽

Vol 12 (2) ◽

pp. 133-145

Author(s):

S. Siva Prasad ◽

R. Madhavi

Keyword(s):

Energy Metabolism ◽

Oxidative Phosphorylation ◽

Bombyx Mori ◽

Larval Stage ◽

Fat Body ◽

Activity Levels ◽

Energy Reserves ◽

Related Energy ◽

Energy Needs ◽

Utilization Patterns

The present study was taken-up with a view to clearly define the role of oxidative phosphorylation vis-a-vis transdeamination in Bombyx mori metamorphosis, under the influence of honey-enriched mulberry diet. Therefore, the study examined the accumulation and utilization patterns of carbohydrate (glycogen, trehalose, glucose) and non-carbohydrate energy reserves (proteins, amino acids) in its fat body during larval, pupal and adult stages. In accordance with Hutchinson’s investment principle, the energy reserves invested during larval stage are partly used in pupal stage and those invested during larval and pupal stages are used in adult stage. Their utilization patterns are correlated with the activity levels of succinate (SDH) and glutamate (GDH) dehydrogenases and aspartate (AAT) and alanine (ALAT) aminotransferases and changes thereof were interpreted in terms of glycolytic oxidative phosphorylation and non-glycolytic transdeamination. The trends in mass incorporation rates vis-à-vis enzyme activities indicated that the metabolism-related energy needs of all metamorphic events are majorly met through a gluconeogenetic mechanism called transdeamination, while the behavioural-related energy demands of larval and pupal stages are fulfilled through glycolytic-based oxidative phosphorylation. The activity trends further indicated that AAT plays major role in meeting the energy needs of larva and pupa, while GDH predominantly meets the energy requirements of reproduction in adults. The honey-enriched mulberry diet showed stage-specific and pathway-specific impacts on energy metabolism. It positively reinforced the energy metabolism in larval stage, but showed no significant effect in pupal and adult stages. Similarly, it showed more promising effect on glycolytic-oxidative phosphorylation and null or neutral effect on transdeamination.

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Bmapaf-1 is Involved in the Response against BmNPV Infection by the Mitochondrial Apoptosis Pathway

Insects ◽

10.3390/insects11090647 ◽

2020 ◽

Vol 11 (9) ◽

pp. 647

Author(s):

Xue-yang Wang ◽

Xin-yi Ding ◽

Qian-ying Chen ◽

Kai-xiang Zhang ◽

Chun-xiao Zhao ◽

...

Keyword(s):

Bombyx Mori ◽

Fluorescent Protein ◽

Functional Domain ◽

Mitochondrial Apoptosis ◽

Apoptosis Pathway ◽

Mitochondrial Apoptosis Pathway ◽

Significant Difference ◽

Budded Virus ◽

Green Fluorescent ◽

Bmn Cells

Discovery of the anti-BmNPV (Bombyx mori nuclearpolyhedrovirus) silkworm strain suggests that some kind of antiviral molecular mechanism does exist but is still unclear. Apoptosis, as an innate part of the immune system, plays an important role in the response against pathogen infections and may be involved in the anti-BmNPV infection. Several candidate genes involved in the mitochondrial apoptosis pathway were identified from our previous study. Bombyx mori apoptosis protease-activating factor-1 (Bmapaf-1) was one of them, but the antiviral mechanism is still unclear. In this study, sequences of BmApaf-1 were characterized. It was found to contain a unique transposase_1 functional domain and share high CARD and NB-ARC domains with other species. Relatively high expression levels of Bmapaf-1 were found at key moments of embryonic development, metamorphosis, and reproductive development. Further, the significant difference in expression of Bmapaf-1 in different tissues following virus infection indicated its close relationship with BmNPV, which was further validated by RNAi and overexpression in BmN cells. Briefly, infection of budded virus with enhanced green fluorescent protein (BV-EGFP) was significantly inhibited at 72 h after overexpression of Bmapaf-1, which was confirmed after knockdown of Bmapaf-1 with siRNA. Moreover, the downstream genes of Bmapaf-1, including Bmnedd2-like caspase (BmNc) and Bmcaspase-1 (Bmcas-1), were upregulated after overexpression of Bmapaf-1 in BmN cells, which was consistent with the RNAi results. Furthermore, the phenomenon of Bmapaf-1 in response to BmNPV infection was determined to be related to apoptosis using the apoptosis inducer NSC348884 and inhibitor Z-DEVD-FMK. Therefore, Bmapaf-1 is involved in the response against BmNPV infection by the mitochondrial apoptosis pathway. This result provides valuable data for clarifying the anti-BmNPV mechanism of silkworms and breeding of resistant silkworm strains.

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