Project description:Host pathways mediating changes in immune states elicited by intestinal microbial colonization are incompletely characterized. Here we describe alterations of the host immune state induced by colonization of germ-free zebrafish larvae with an intestinal microbial community or single bacterial species. We show that microbiota-induced changes in intestinal leukocyte subsets and whole-body host gene expression are dependent on the innate immune adaptor gene myd88. Similar patterns of gene expression are elicited by colonization with conventional microbiome, as well as mono-colonization with two different zebrafish commensal bacterial strains. By studying loss-of-function myd88 mutants, we find that colonization suppresses Myd88 at the mRNA level. Tlr2 is essential for microbiota-induced effects on myd88 transcription and intestinal immune cell composition.
Project description:Vertebrates are colonized at birth by complex microbial communities (microbiota) that influence diverse aspects of host biology. We have used a functional genomics approach to identify zebrafish genes that are differentially expressed in response to the microbiota. We assessed RNA expression profiles from zebrafish larvae at 6 days post-fertilization (dpf) that were either raised continuously in the absence of any microorganism (germ-free or GF), or raised GF through 3dpf then colonized with a normal zebrafish microbiota (conventionalized or CONVD). Total RNA was purified from pooled intact zebrafish larvae (28-80 larvae/pool, 3 biological replicate pools/condition) using Trizol reagent (Invitrogen) followed by DNase I digestion (DNA-Free, Ambion) according to manufacturers' protocols. Total RNA from each replicate pool (12ug RNA/replicate) was used as template for independent cDNA synthesis and in vitro transcription reactions (BioArray HighYield RNA Transcript Labeling Kit; Enzo Life Sciences) to generate biotinylated cRNA targets. cRNA targets (20ug/replicate) were fragmented using standard methods. Hybridization and scanning were performed using standard Affymetrix protocol. Raw expression values were normalized (Invariant set method) and modeled (PM-MM model), and present/absent calls were generated using dChip software (build date Dec.11, 2005).
Project description:Vertebrates are colonized at birth by complex microbial communities (microbiota) that influence diverse aspects of host biology. We have used a functional genomics approach to identify zebrafish genes that are differentially expressed in response to the microbiota. We assessed RNA expression profiles from zebrafish larvae at 6 days post-fertilization (dpf) that were either raised continuously in the absence of any microorganism (germ-free or GF), or raised GF through 3dpf then colonized with a normal zebrafish microbiota (conventionalized or CONVD).
Project description:Transcriptional profiling of 3dpf wild type zebrafish larvae treated with 20mM PTZ for 30 and 90 minutes compared with 3dpf wild type control untreated zebrafish larvae.
Project description:Zebrafish is a natural host of various Mycobacterium species and a surrogate model organism for tuberculosis research. Mycobacterium marinum (M. marinum) is evolutionarily most closely related to M. tuberculosis and shares the majority of virulence genes. Although zebrafish is not a natural host of the human pathogen, we have previously demonstrated successful robotic infection of zebrafish embryos with M. tuberculosis and performed drug treatment of the infected larvae. In the present study we examined for how long M. tuberculosis can be propagated in zebrafish larvae and tested a time series of infected larvae to study the transcriptional response via Illumina RNAseq. Granuloma-like structures carrying fluorescently labeled M. tuberculosis could be detected up to 9 days post infection. The continued presence of viable M. tuberculosis in the zebrafish larvae was further confirmed using the molecular bacterial load assay. The infected larvae showed a clear and specific transcriptional immune response with a high similarity to the response of zebrafish larvae infected with the surrogate species M. marinum. We conclude that M. tuberculosis can be propagated in zebrafish larvae for at least one week after infection and provide further evidence that M. marinum is a good surrogate model for M. tuberculosis.
Project description:Despite the involvement of several serine hydrolases (SHs) in the metabolism of xenobiotics such as dibutyl phthalate (DBP), no study has focused on mapping this enzyme class in zebrafish, a model organism frequently used in ecotoxicology. Here, we survey and identify active SHs in zebrafish larvae and search for biological markers of SH type after exposition to DBP. Zebrafish were exposed to 0, 5, and 100 µg/L DBP from 4 to 120 h post-fertilization. A significant decrease in vitellogenin expression level of about 2-fold compared to the control was found in larvae exposed to 100 µg/L DBP for 120h. The first comprehensive profiling of active SHs in zebrafish proteome was achieved with an activity-based protein profiling (ABPP) approach. Among 49 SHs identified with high confidence, one was the carboxypeptidase ctsa overexpressed in larvae exposed to 100 µg/L DBP for 120h. To the best of our knowledge, this is the first time that a carboxypeptidase has been identified as deregulated following exposure to DBP. The overall results indicate that targeted proteomics approaches such as ABPP can therefore be an asset for understanding the mechanism of action related to xenobiotics in ecotoxicology.
2023-03-11 | PXD038229 | Pride
Project description:Bacterial communities associated with zebrafish larvae
Project description:Transcriptional profiling of zebrafish larvae comparing control with AgNO3 or AgNPs exposed zebrafish larvae. Three-condition experiment, Control vs. AgNO3 and Control vs. AgNPs exposed zebrafish. Biological replicates: 6 control replicates, 6 AgNO3 replicates and 6 AgNPs replicates.
Project description:Purpose: We report the application of NGS for the impacts of BDE47 exposure on the miRNA expression profiling of zebrafish larvae. Methods: miRNA profiles of 6-day-old BDE47-treated and control zebrafish larvae were generated by deep sequencing using Illumina Hisq 2000 platform. The sequence reads that passed quality filters were analyzed at the transcript isoform level with TopHat followed by Cufflinks. Results: Compared BDE47 treatments with solvent control, a dozen of validated zebrafish miRNAs, including dre-miR-142a-3p, dre-miR-142b-5p, dre-miR-144-3p, dre-miR-146a, dre-miR-190a, dre-miR-219-5p, dre-miR-301b-3p, dre-miR-459-5p, rno-miR-33-5p, dre-miR-735-3p, and dre-miR-735-5p, significantly changed their expressions. Conclusions: This study provides a framework for the application of high-throughput sequencing towards characterization of the impacts of BDE47 on whole zebrafish larval miRNA expression profiling.