scholarly journals Dense time-course gene expression profiling of the Drosophila melanogaster innate immune response

2020 ◽  
Author(s):  
Florencia Schlamp ◽  
Sofie Delbare ◽  
Angela M. Early ◽  
Martin T. Wells ◽  
Sumanta Basu ◽  
...  

Abstract BackgroundImmune responses need to be initiated rapidly, and maintained as needed, to prevent establishment and growth of infections. At the same time, resources need to be balanced with other physiological processes. On the level of transcription, studies have shown that this balancing act is reflected in tight control of the initiation kinetics and shutdown dynamics of specific immune genes. ResultsTo investigate expression dynamics and trade-offs after infection genome-wide and with high temporal resolution, we performed an RNA-seq time course on D. melanogaster with 20 time points post-LPS injection. A combination of methods, including spline fitting, cluster analysis, and Granger Causality inference, allowed detailed dissection of expression profiles, lead-lag interactions, and functional annotation of genes through guilt-by-association. We identified genes encoding antimicrobial peptides and co-expressed, less well characterized genes, as immediate-early response genes with a sustained up-regulation up to five days after stimulation. In contrast, stress response genes and additional immune genes, among which were Bomanins, demonstrated early and transient responses. We further observed a strong trade-off with metabolic genes, which strikingly recovered to pre-infection levels before the immune response was fully resolved. ConclusionsThis high-dimensional dataset enabled the comprehensive study of immune response dynamics through the parallel application of multiple temporal data analysis methods. Multivariate Granger causality analysis proved to be a valuable addition to classical time course analysis methods such as clustering, due to its ability to define directed networks of lead-lag patterns.

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Florencia Schlamp ◽  
Sofie Y. N. Delbare ◽  
Angela M. Early ◽  
Martin T. Wells ◽  
Sumanta Basu ◽  
...  

Abstract Background Immune responses need to be initiated rapidly, and maintained as needed, to prevent establishment and growth of infections. At the same time, resources need to be balanced with other physiological processes. On the level of transcription, studies have shown that this balancing act is reflected in tight control of the initiation kinetics and shutdown dynamics of specific immune genes. Results To investigate genome-wide expression dynamics and trade-offs after infection at a high temporal resolution, we performed an RNA-seq time course on D. melanogaster with 20 time points post Imd stimulation. A combination of methods, including spline fitting, cluster analysis, and Granger causality inference, allowed detailed dissection of expression profiles, lead-lag interactions, and functional annotation of genes through guilt-by-association. We identified Imd-responsive genes and co-expressed, less well characterized genes, with an immediate-early response and sustained up-regulation up to 5 days after stimulation. In contrast, stress response and Toll-responsive genes, among which were Bomanins, demonstrated early and transient responses. We further observed a strong trade-off with metabolic genes, which strikingly recovered to pre-infection levels before the immune response was fully resolved. Conclusions This high-dimensional dataset enabled the comprehensive study of immune response dynamics through the parallel application of multiple temporal data analysis methods. The well annotated data set should also serve as a useful resource for further investigation of the D. melanogaster innate immune response, and for the development of methods for analysis of a post-stress transcriptional response time-series at whole-genome scale.


2020 ◽  
Author(s):  
Florencia Schlamp ◽  
Sofie Y. N. Delbare ◽  
Angela M. Early ◽  
Martin T. Wells ◽  
Sumanta Basu ◽  
...  

ABSTRACTImmune responses need to be initiated rapidly, and maintained as needed, to prevent establishment and growth of infections. Still, immune genes differ in both initiation kinetics and shutdown dynamics. Here, we performed an RNA-seq time course on D. melanogaster with 20 time points post-LPS injection. A combination of methods, including spline fitting, cluster analysis, and Granger Causality inference, allowed detailed dissection of expression profiles and functional annotation of genes through guilt-by-association. We identified antimicrobial peptides as immediate-early response genes with a sustained up-regulation up to five days after stimulation, and genes in the IM family as having early and transient responses. We further observed a strong trade-off with metabolic genes, which strikingly recovered to pre-infection levels before the immune response was fully resolved. This high-dimensional dataset enables the comprehensive study of immune response dynamics through the parallel application of multiple temporal data analysis methods.


2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Hao Zhou ◽  
Shun Chen ◽  
Mingshu Wang ◽  
Renyong Jia ◽  
Dekang Zhu ◽  
...  

Abstract Both Tembusu virus (TMUV) and goose parvovirus (GPV) are causative agents of goose disease. However, the host immune response of the goose against these two different categories of virus has not been well documented. Here, we compared the clinical symptoms and pathological characteristics, antigen distribution and intensity, and expression of immune-related genes in TMUV- and GPV- infected goose. The immunohistochemistry analysis demonstrated that GPV was primarily located in the liver, lung, small intestine, and rectum, while TMUV was situated in the liver, brain, spleen, and small intestine. The induction of IFNγ and proinflammatory cytokines is highly associated with the distribution profiles of antigen and CD8α+ molecules. The effector function of CD8 T cells may be accomplished by the secretion of IFNγ together with high expression of proinflammatory cytokines such as IL1 and IL6. Remarkably, significant increases in the transcription of immune genes were observed after infection, which suggested that both GPV and TMUV can effectively induce immune response in goose PMBCs. This study will provide fundamental information for goose molecular immunology in defending against pandemic viruses.


PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6359 ◽  
Author(s):  
Yu Zhang ◽  
Yang Chen ◽  
Tiantian Gu ◽  
Qi Xu ◽  
Guoqiang Zhu ◽  
...  

Persistent colonization of the avian reproductive tract by Salmonella enterica serovar Enteritidis (SE) negatively affects egg production and contaminates the egg. The immune function of the ovary and oviduct is essential for protection from infection and for the production of wholesome eggs. However, the immune response of laying ducks during SE infection is not well-understood. In this study, ducks (Anas platyrhynchos) were infected with SE and were systematically monitored for fecal shedding during a 13-week period. We also assessed bacterial distribution in the reproductive tract and classified infected ducks as resistant or susceptible based on the presence of tissue lesions and on SE isolation from fecal samples. We found that infected animals had persistent, but intermittent, bacterial shedding that resulted in the induction of carrier ducks. Laying rate and egg quality were also decreased after SE infection (P < 0.05). SE readily colonized the stroma, small follicle, isthmus, and vagina in the reproductive tracts of susceptible ducks. Immunoglobulin (IgA, IgG, IgM) levels were higher in susceptible ducks compared with resistant birds (P < 0.05); T-lymphocyte subpopulations (CD3+, CD4+, CD8+) displayed the opposite trend. qRT-PCR analysis was used to examine expression profiles of immune response genes in the reproductive tract of infected ducks. The analysis revealed that immune genes, including toll-like receptors (TLR2, TLR4-5, TLR15, TLR21), NOD-like receptors (NOD1, NLRX1, NLRP12), avian β-defensins (AvβD4-5, AvβD7, AvβD12), cytokines (IL-6, IL-1β, IFN-γ), and MyD88 were markedly upregulated in the reproductive tracts of SE-infected ducks (all P < 0.05); TLR3, TLR7, NLRC3, NLRC5, and TNF-α were significantly downregulated. These results revealed that SE infection promoted lower egg production and quality, and altered the expression of TLRs, NLRs, AvβDs, and cytokine family genes. These findings provide a basis for further investigation of the physiological and immune mechanisms of SE infection in laying ducks.


Author(s):  
P. Sivasankar ◽  
K. Riji John ◽  
M. Rosalind George ◽  
M. Mohamed Mansoor ◽  
P. Magesh Kumar ◽  
...  

Background: Control of viral disease outbreaks in aquaculture and minimizing the loss of production can be achieved by development of effective vaccines. Efficacy of these vaccines can be improved by using adjuvants, immunostimulants or vaccine carriers. In this study, inactivated similar damselfish virus (SRDV) vaccine was prepared and expression profiles of immune related genes against virus challenge of the vaccine were investigated in seabass (Lates calcarifer). Methods: Formalin-inactivated virus vaccine was developed to assess its immune responses to SRDV challenge in fish. The immune response was induced by intra-peritoneal injection with inactivated viral vaccine added Quil-A® adjuvant. The transcriptional levels of immune genes IRF-7 and IL-10 were evaluated in the spleen and kidney of seabass from different groups by quantitative real-time RT-PCR assays. Result: Expression profiles of both genes (IRF-7 and IL-10) in the kidney and spleen of seabass immunized with vaccine added adjuvant were up-regulated at 48 hpi of the virus. In comparison, spleen of seabass immunized with vaccine added adjuvant showed highest expression profiles than kidney. The current study provides evidence for the presence of expression profiles of immune-related genes during the SRDV infection. The study also strongly suggests that Quil-A® adjuvant enhances the immune response of the vaccine candidates.


2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Yan Ren ◽  
Christian I. Hong ◽  
Sookkyung Lim ◽  
Seongho Song

Identification of rhythmic gene expression from metabolic cycles to circadian rhythms is crucial for understanding the gene regulatory networks and functions of these biological processes. Recently, two algorithms, JTK_CYCLE and ARSER, have been developed to estimate periodicity of rhythmic gene expression. JTK_CYCLE performs well for long or less noisy time series, while ARSER performs well for detecting a single rhythmic category. However, observing gene expression at high temporal resolution is not always feasible, and many scientists are interested in exploring both ultradian and circadian rhythmic categories simultaneously. In this paper, a new algorithm, named autoregressive Bayesian spectral regression (ABSR), is proposed. It estimates the period of time-course experimental data and classifies gene expression profiles into multiple rhythmic categories simultaneously. Through the simulation studies, it is shown that ABSR substantially improves the accuracy of periodicity estimation and clustering of rhythmic categories as compared to JTK_CYCLE and ARSER for the data with low temporal resolution. Moreover, ABSR is insensitive to rhythmic patterns. This new scheme is applied to existing time-course mouse liver data to estimate period of rhythms and classify the genes into ultradian, circadian, and arrhythmic categories. It is observed that 49.2% of the circadian profiles detected by JTK_CYCLE with 1-hour resolution are also detected by ABSR with only 4-hour resolution.


e-Finanse ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 20-26
Author(s):  
Taiwo A. Muritala ◽  
Muftau A. Ijaiya ◽  
Olatanwa H. Afolabi ◽  
Abdulrasheed B. Yinus

AbstractThis paper examines the causality between fraud and bank performance in Nigeria over the period 2000-2016 for quarterly financial data using Johansen’s Multivariate Cointegration Model and Vector Autoregressive (VAR) Granger Causality analysis. The results show a long-run relationship between the variables. Bank performance was found to be linked to Granger fraud variables and vice versa at 10% significant level. This study reveals that there was a direct causal relationship between bank performance and fraud because increase in fraudulent activities in the banking sector leads to reduction in bank performance. Hence, this study recommends that internal control systems of banks should be strengthened so as to detect and prevent fraud. In this way, bank assets would be protected.


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