Transcriptome Profiling Reveals a Novel Mechanism of Antiviral Immunity Upon Sacbrood Virus Infection in Honey Bee Larvae (Apis cerana)

The honey bee is one of the most important pollinators in the agricultural system and is responsible for pollinating a third of all food we eat. Sacbrood virus (SBV) is a member of the virus family Iflaviridae and affects honey bee larvae and causes particularly devastating disease in the Asian honey bees, Apis cerana. Chinese Sacbrood virus (CSBV) is a geographic strain of SBV identified in China and has resulted in mass death of honey bees in China in recent years. However, the molecular mechanism underlying SBV infection in the Asian honey bee has remained unelucidated. In this present study, we employed high throughput next-generation sequencing technology to study the host transcriptional responses to CSBV infection in A. cerana larvae, and were able to identify genome-wide differentially expressed genes associated with the viral infection. Our study identified 2,534 differentially expressed genes (DEGs) involved in host innate immunity including Toll and immune deficiency (IMD) pathways, RNA interference (RNAi) pathway, endocytosis, etc. Notably, the expression of genes encoding antimicrobial peptides (abaecin, apidaecin, hymenoptaecin, and defensin) and core components of RNAi such as Dicer-like and Ago2 were found to be significantly upregulated in CSBV infected larvae. Most importantly, the expression of Sirtuin target genes, a family of signaling proteins involved in metabolic regulation, apoptosis, and intracellular signaling was found to be changed, providing the first evidence of the involvement of Sirtuin signaling pathway in insects’ immune response to a virus infection. The results obtained from this study provide novel insights into the molecular mechanism and immune responses involved in CSBV infection, which in turn will contribute to the development of diagnostics and treatment for the diseases in honey bees.

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Chinese Sacbrood virus infection in Asian honey bees (Apis cerana cerana) and host immune responses to the virus infection

Journal of Invertebrate Pathology ◽

10.1016/j.jip.2017.09.006 ◽

2017 ◽

Vol 150 ◽

pp. 63-69 ◽

Cited By ~ 7

Author(s):

Liu Shan ◽

Wang Liuhao ◽

Guo Jun ◽

Tang Yujie ◽

Chen Yanping ◽

...

Keyword(s):

Virus Infection ◽

Immune Responses ◽

Honey Bees ◽

Apis Cerana ◽

Apis Cerana Cerana ◽

Host Immune Responses ◽

Sacbrood Virus

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Antiviral Activities of a Medicinal Plant Extract Against Sacbrood Virus in Honeybees

Virology Journal ◽

10.1186/s12985-021-01550-y ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Liping Sun ◽

Xueqi Zhang ◽

Shufa Xu ◽

Chunsheng Hou ◽

Jin Xu ◽

...

Keyword(s):

Honey Bees ◽

Apis Cerana ◽

Larval Growth ◽

Antiviral Agent ◽

Antiviral Effect ◽

Absolute Quantification ◽

Chinese Medicinal Herb ◽

Sacbrood Virus ◽

Antiviral Activities ◽

Potential Strategy

Abstract Background Sacbrood is an infectious disease of the honey bee caused by Scbrood virus (SBV) which belongs to the family Iflaviridae and is especially lethal for Asian honeybee Apis cerana. Chinese Sacbrood virus (CSBV) is a geographic strain of SBV. Currently, there is a lack of an effective antiviral agent for controlling CSBV infection in honey bees. Methods Here, we explored the antiviral effect of a Chinese medicinal herb Radix isatidis on CSBV infection in A. cerana by inoculating the 3rd instar larvae with purified CSBV and treating the infected bee larvae with R. isatidis extract at the same time. The growth, development, and survival of larvae between the control and treatment groups were compared. The CSBV copy number at the 4th instar, 5th instar, and 6th instar larvae was measured by the absolute quantification PCR method. Results Bioassays revealed that R. isatidis extract significantly inhibited the replication of CSBV, mitigated the impacts of CSBV on larval growth and development, reduced the mortality of CSBV-infected A. cerana larvae, and modulated the expression of immune transcripts in infected bees. Conclusion Although the mechanism underlying the inhibition of CSBV replication by the medicine plant will require further investigation, this study demonstrated the antiviral activity of R. isatidis extract and provides a potential strategy for controlling SBV infection in honey bees.

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Beeporter: a high-throughput tool for non-invasive analysis of honey bee virus infection

10.1101/2021.01.13.426606 ◽

2021 ◽

Author(s):

Jay D. Evans ◽

Olubukola Banmeke ◽

Evan C. Palmer-Young ◽

Yanping Chen ◽

Eugene V. Ryabov

Keyword(s):

Virus Infection ◽

Honey Bee ◽

High Throughput ◽

Honey Bees ◽

High Throughput Screening ◽

Fluorescent Protein ◽

Imaging System ◽

Uv Light ◽

Light Sources ◽

Deformed Wing Virus

ABSTRACTHoney bees face numerous pests and pathogens but arguably none are as devastating as Deformed wing virus (DWV). Development of antiviral therapeutics and virus-resistant honey bee lines to control DWV in honey bees is slowed by the lack of a cost-effective high-throughput screening of DWV infection. Currently, analysis of virus infection and screening for antiviral treatments in bees and their colonies is tedious, requiring a well-equipped molecular biology laboratory and the use of hazardous chemicals. Here we utilize a cDNA clone of DWV tagged with green fluorescent protein (GFP) to develop the Beeporter assay, a method for detection and quantification of DWV infection in live honey bees. The assay involves infection of honey bee pupae by injecting a standardized DWV-GFP inoculum, followed by incubation for up to 44 hours. GFP fluorescence is recorded at intervals via commonly available long-wave UV light sources and a smartphone camera or a standard ultraviolet transilluminator gel imaging system. Nonlethal DWV monitoring allows high-throughput screening of antiviral candidates and a direct breeding tool for identifying honey bee parents with increased antivirus resistance. For even more rapid drug screening, we also describe a method for screening bees using 96-well trays and a spectrophotometer.

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Complete genome sequence of sacbrood virus isolated from Asiatic honey bee Apis cerana indica in India

VirusDisease ◽

10.1007/s13337-018-0490-0 ◽

2018 ◽

Vol 29 (4) ◽

pp. 453-460 ◽

Cited By ~ 1

Author(s):

R. Aruna ◽

M. R. Srinivasan ◽

V. Balasubramanian ◽

R. Selvarajan

Keyword(s):

Honey Bee ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Apis Cerana ◽

Sacbrood Virus ◽

Apis Cerana Indica

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Flight muscles degenerate by programmed cell death after migration in the wheat aphid, Sitobion avenae

BMC Research Notes ◽

10.1186/s13104-019-4708-z ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 1

Author(s):

Honglin Feng ◽

Xiao Guo ◽

Hongyan Sun ◽

Shuai Zhang ◽

Jinghui Xi ◽

...

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Molecular Mechanism ◽

Differentially Expressed Genes ◽

Flight Muscle ◽

Sitobion Avenae ◽

Differentially Expressed ◽

Terminal Deoxynucleotidyl Transferase ◽

Muscle Degeneration ◽

Flight Muscles

Abstract Objective Previous studies showed that flight muscles degenerate after migration in some aphid species; however, the underlying molecular mechanism remains virtually unknown. In this study, using the wheat aphid, Sitobion avenae, we aim to investigate aphid flight muscle degeneration and the underlying molecular mechanism. Results Sitobion avenae started to differentiate winged or wingless morphs at the second instar, the winged aphids were fully determined at the third instar, and their wings were fully developed at the fourth instar. After migration, the aphid flight muscles degenerated via programmed cell death, which is evidenced by a Terminal deoxynucleotidyl transferase dUTP-biotin nick-end labeling assay. Then, we identified a list of differentially expressed genes before and after tethered flights using differential-display reverse transcription-PCR. One of the differentially expressed genes, ubiquitin-ribosomal S27a, was confirmed using qPCR. Ubiquitin-ribosomal S27a is drastically up regulated following the aphids’ migration and before the flight muscle degeneration. Our data suggested that aphid flight muscles degenerate after migration. During flight muscle degeneration, endogenous proteins may be degraded to reallocate energy for reproduction.

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Dynamics of Apis cerana Sacbrood Virus (AcSBV) Prevalence in Apis cerana (Hymenoptera: Apidae) in Northern Taiwan and Demonstration of its Infection in Apis mellifera (Hymenoptera: Apidae)

Journal of Economic Entomology ◽

10.1093/jee/toz174 ◽

2019 ◽

Vol 112 (5) ◽

pp. 2055-2066 ◽

Cited By ~ 1

Author(s):

Chong-Yu Ko ◽

Zong-Lin Chiang ◽

Ruo-Jyun Liao ◽

Zih-Ting Chang ◽

Ju-Chun Chang ◽

...

Keyword(s):

Phylogenetic Analysis ◽

Apis Mellifera ◽

Honey Bee ◽

Apis Cerana ◽

Cross Infection ◽

Prevalence Rates ◽

Sacbrood Virus ◽

Northern Taiwan ◽

Long Term Survey

AbstractSince 2016, Apis cerana sacbrood virus (AcSBV) has been recorded in Taiwan. It is epizootic in Apis cerana (Hymenoptera: Apidae) and causing serious loss of A. cerana. Herein, we performed a long-term survey of AcSBV prevalence in the populations of A. cerana in Northern Taiwan from January 2017 to July 2018. The surveillance of AcSBV prevalence in A. mellifera (Hymenoptera: Apidae) populations was starting and further confirmed by sequencing since April 2017; thus, these data were also included in this survey. In our survey, the average prevalence rates of AcSBV were 72 and 53% in A. cerana and A. mellifera, respectively, in 2017, which decreased to 45 and 27% in 2018. For the spatial analysis of AcSBV in two honey bee populations, Hsinchu showed the highest prevalence, followed by New Taipei, Yilan, Taipei, and Keelung, suggesting that AcSBV might have come from the southern part of Taiwan. Interestingly, the AcSBV prevalence rates from A. cerana and A. mellifera cocultured apiaries gradually synchronized. The result of phylogenetic analysis and comparison of the annual AcSBV prevalence in A. cerana-only, A. mellifera-only, and A. cerana/A. mellifera cocultured sample sites indicate cross-infection between A. cerana and A. mellifera; however, AcSBV may lose the advantage of virulence in A. mellifera. The evidence suggested that the transmission of AcSBV might occur among these two honey bee species in the field. Therefore, A. mellifera may serve as a guard species to monitor AcSBV in A. cerana, but the cross-infection still needs to be surveyed.

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Screening of Differentially Expressed Microsporidia Genes from Nosema ceranae Infected Honey Bees by Suppression Subtractive Hybridization

Insects ◽

10.3390/insects11030199 ◽

2020 ◽

Vol 11 (3) ◽

pp. 199

Author(s):

Zih-Ting Chang ◽

Chong-Yu Ko ◽

Ming-Ren Yen ◽

Yue-Wen Chen ◽

Yu-Shin Nai

Keyword(s):

Gene Expression ◽

Real Time ◽

Differentially Expressed Genes ◽

Honey Bees ◽

Physiological Mechanism ◽

Subtractive Hybridization ◽

Infection Process ◽

Nosema Ceranae ◽

Differentially Expressed ◽

Suppressive Subtractive Hybridization

The microsporidium Nosema ceranae is a high prevalent parasite of the European honey bee (Apis mellifera). This parasite is spreading across the world into its novel host. The developmental process, and some mechanisms of N. ceranae-infected honey bees, has been studied thoroughly; however, few studies have been carried out in the mechanism of gene expression in N. ceranae during the infection process. We therefore performed the suppressive subtractive hybridization (SSH) approach to investigate the candidate genes of N. ceranae during its infection process. All 96 clones of infected (forward) and non-infected (reverse) library were dipped onto the membrane for hybridization. A total of 112 differentially expressed sequence tags (ESTs) had been sequenced. For the host responses, 20% of ESTs (13 ESTs, 10 genes, and 1 non-coding RNA) from the forward library and 93.6% of ESTs (44 ESTs, 28 genes) from the reverse library were identified as differentially expressed genes (DEGs) of the hosts. A high percentage of DEGs involved in catalytic activity and metabolic processes revealed that the host gene expression change after N. ceranae infection might lead to an unbalance of physiological mechanism. Among the ESTs from the forward library, 75.4% ESTs (49 ESTs belonged to 24 genes) were identified as N. ceranae genes. Out of 24 N. ceranae genes, nine DEGs were subject to real-time quantitative reverse transcription PCR (real-time qRT-PCR) for validation. The results indicated that these genes were highly expressed during N. ceranae infection. Among nine N. ceranae genes, one N. ceranae gene (AAJ76_1600052943) showed the highest expression level after infection. These identified differentially expressed genes from this SSH could provide information about the pathological effects of N. ceranae. Validation of nine up-regulated N. ceranae genes reveal high potential for the detection of early nosemosis in the field and provide insight for further applications.

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