Ac106/107 affects production of infectious progeny BV by regulating transcription of late viral genes and host cell energy metabolism

Abstract

BACKGROUND AcMNPV is a model organism of baculovirus, and Spodoptera frugiperda is one of its hosts. Disclosing the role of ac106/107 in AcMNPV infecting Spodoptera frugiperda 9 (Sf9) cells is of great significance for modifying AcMNPV as a microbial insecticide. This work constructed recombinant baculovirus that knocking out, repairment and overexpression of ac106/107 and explored the effects of Ac106/107 on the proliferation of progeny viruses. Moreover, the potential mechanism and targets of ac106/107 were further revealed. RESULTS First, compared with the Bacmid‐EGFP transfection group, the progeny virus does not proliferate after knocking out of ac106/107, and the proliferation ability increases by 14.5% at 72 h post transfection (h p.t.) when overexpression of ac106/107. However, knockout, repairment and overexpression of ac106/107 have no effect on viral DNA replication. Secondly, Ac106/107‐EGFP was located in the cytoplasm and nucleus. Transcription level of late viral genes and viral RNA polymerase subunit genes in the Bacmidac106/107KO‐EGFP transfection group and Bacmid‐Ac106/107‐EGFP transfection group was reduced and increased, respectively. Thirdly, AcMNPV would increase the glucose utilization and lactate consumption of the host Sf9 cells, and Bacmidac106/107KO‐EGFP transfection group had lower glucose consumption and lactic acid accumulation than Bacmid‐EGFP, Bacmidac106/107KO ‐Ac106/107(rep)‐EGFP and Bacmid‐Ac106/107‐EGFP transfection groups. CONCLUSION Ac106/107 can enter the nucleus and affect transcription of viral RNA polymerase subunit genes, which in turn affects the transcription of late genes, and ultimately affects virus proliferation and energy metabolism in host cells. © 2021 Society of Chemical Industry.

Protein-Gene Orthology in Baculoviridae: An Exhaustive Analysis to Redefine the Ancestrally Common Coding Sequences

“…These will be the conditions to change the ancestrally common coding core of Baculoviridae . Particularly, it will be necessary to inspect more thoroughly if CUN053, CUN076 and CUN103 proteins have a common ancestry with Ac106 (a nuclear protein that modulate transcriptional processes) [ 59 ], Lef11 (a nuclear protein involved in baculoviral DNA replication) [ 60 , 61 ] and Ac131 (a polyhedron envelope/calyx protein) [ 4 ], respectively. The activities of these polypeptides seem to be important in the infection cycle, and so, it is possible that the sequences detected in the CuniNPV genome are also part of the preserved genomic fraction of Baculoviridae .…”

YBac: A novel and simple baculovirus system for heterologous protein production in Spodoptera frugiperda 9 (Sf9) cells

“…The titers of all supernatants were determined by an endpoint dilution method as previously described. [ 18 ] Then the viral yields were calculated using the Spearman‐Karber method. [ 19 ] Images are representative of three independent experiments.…”

Genetic engineering of baculovirus-insect cell system to improve protein production

“…This multiplex system can significantly enhance the potential of CRISPR/Cas9-based multiplex genome engineering in baculoviruses and will be beneficial in antiviral therapy. Wang et al (2021) have also employed the CRISPR/Cas9 system to construct a recombinant baculovirus that knocks out ac106/107. They showed that ac106/107 could enter the nucleus and affect the transcription of viral RNA polymerase, which in turn could change the transcription of late genes and alter the virus proliferation.…”