Project description:We report the application of CAGE (Cap Analysis of Gene Expression) on collections of Daphnia pulex individuals representing three major developmental states. This submission comes from a project of Michael Lynch and was funded by a grant from the National Institutes of Health entitled 'Population Genomics of Daphnia pulex' (Project Number: 1R01GM101672-01A1).
Project description:We use a custom microarray for the crustacean Daphnia pulex to investigate gene expression in males, juvenile females and pregnant females. Keywords: sex-biased, developmental
Project description:Determine gene expression in daphnia exposed to biotic and abiotic stressors. Identify in Daphnia pulex unique gene regulatory patterns involved in the regulation of limited phosphorous. One-condition experiment: Exposed Daphnia pulex for 5 days to phosphorous-limited algae. Biological replicates: 4 exposures, 4 nonexposed controls, grown and harvested in groups of 20 daphnia. One replicate per array.
Project description:This SuperSeries is composed of the following subset Series: GSE25841: Evolutionary Diversification of Duplicated Genes; Experiment A GSE25843: Evolutionary Diversification of Duplicated Genes; Experiments B-I, M-P GSE25845: Evolutionary Diversification of Duplicated Genes; Experiments B-I GSE25850: Evolutionary Diversification of Duplicated Genes; Experiment J GSE25851: Evolutionary Diversification of Duplicated Genes; Experiment L, K GSE25852: Empirical Annotation of the Daphnia pulex genome; Experiment B GSE25855: Empirical Annotation of the Daphnia pulex genome; Experiment A GSE25856: Empirical Annotation of the Daphnia pulex genome; Experiment C Refer to individual Series
Project description:Determine gene expression in daphnia exposed to biotic and abiotic stressors. Identify in Daphnia pulex unique gene regulatory patterns involved in the regulation of limited phosphorous.
Project description:Daphnia (Daphnia pulex) is a small planktonic crustacean and a key constituent of aquatic ecosystems. It is commonly used as a model organism for studying environmental toxic challenges. In the past decade, a Daphnia genomic information and proteomic dataset has been developed. This dataset has expanded the opportunity to relate toxicological effects with “Daphnia proteomics” as it integrates proteomic knowledge in Daphnia, those approach will provide greater insights for toxicological research. In order to exploit Daphnia for ecotoxicological research, information on the post-translational modification (PTM) of proteins is necessary as this is a critical regulator of biological processes. Acetylation of lysine (Kac) is a reversible and highly regulated PTM that is associated with diverse biological functions. However, a comprehensive description of Kac in Daphnia is not yet available. Here, to understand the cellular distribution of lysine acetylation in Daphnia, we identified 98 acetylation sites in 65 proteins by immunoprecipitation using an anti-acetyllysine antibody and an liquid chromatography system supported by mass spectroscopy. We identified 28 acetylated sites connected with metabolic proteins and 6 acetylated enzymes associated with the TCA cycle in Daphnia. From GO and KEGG enrichment analyses, we showed that Kac in D. pulex is highly enriched in proteins associated with metabolic processes. Our data provide the first global analysis of lysine acetylation in D. pulex. The expanded proteomic dataset will be an important resource for the functional analysis of Kac in D. pulex and it will be nice to have a first step done using a promising future model organism.
Project description:Investigation of gene expression level changes in Daphnia pulex MFP strain between in the presence or absence of Chaoborus kairomone.
Project description:Despite a significant increase in genomic data, our knowledge of gene functions and their transcriptional responses to environmental stimuli remains limited. Here, we use the model keystone species Daphnia pulex to study environmental responses of genes in the context of their gene family history to better understand the relationship between genome structure and gene function in response to environmental stimuli. Daphnia were exposed to five different treatments, each consisting of a diet supplemented with one of five cyanobacterial species, and a control treatment consisting of a diet of only green algae. Differential gene expression profiles of Daphnia exposed to each of these five cyanobacterial species showed that genes with known functions are more likely to be shared by different expression profiles whereas genes specific to the lineage of Daphnia are more likely to be unique to a given expression profile. Furthermore, while only a small number of non-lineage specific genes was conserved across treatment type, there was a high degree of overlap in expression profiles at the functional level. The conservation of functional responses across the different cyanobacterial treatments can be attributed to the treatment specific expression of different paralogous genes within the same gene family. Comparison with available gene expression data in the literature suggests differences in nutritional composition in diets with cyanobacterial species compared to diets of green algae as a primary driver for cyanobacterial effects on Daphnia. We conclude that conserved functional responses in Daphnia across different cyanobacterial treatments are mediated through alternate regulation of paralogous gene families. Whole transcriptome dual color arrays were used to discover differentially expressed genes following sub-lethal exposure to five cyanobacteria in D. pulex. RNA was isolated from eight independent and concurrently replicated exposures of Daphnia to control and five cyanobacteria conditions. RNA was hybridized to microarrays using a standard, control vs. treated design that included dye swaps. Cyanobacteria were Anabaena (ANA), Aphanizomenon (Aph), Cylindrospermopsis (Cyl), Nodularia (Nod) and Oscillatoria (Osl).
Project description:Background: In the life history of Daphnia, the reproductive mode of parthenogenesis and sexual reproduction alternate in aquatic ecosystem, which are often affected by environmental and genetic factor. Although several functional genes on reproductive transition of Daphnia had been determined, molecular mechanism on the reproductive mode of Daphnia are still not known well, including differentially expressed genes in different developmental stages. Results: In this study, four developmental stages, juvenile female (JF), parthenogenetic female (PF), sexual female (SF) and male (M), of D. similoides sinensis were performed for transcriptome sequence, and candidate genes related to male sex determination were screened. A total of 110437 transcripts were obtained and assembled into 22996 unigenes. In the four developmental stages (JF, PF, SF and M), the number of unique unigenes is respectively 2863, 445, 437 and 586, and the number of common unigenes is 9708. The differentially expressed genes (DEGs) between male and other three female stages (M vs JF, M vs PF and M vs SF) were obtained. The GO gene enrichment analysis showed that the up-regulated genes in male were mainly enriched in hydrolase activity and peptidase activity. Thirty-six candidate genes related to male sex determination in male were significantly higher expression than those in the other three stages, including one Doublesex (Dsx) gene, one laminin gene, five trypsin genes and one serine protease genes, and one chitin synthase gene and two chitinase genes. In addition, in D. similoides sinensis male, the relative expression levels of two genes (Dsx1, antp) related to male sex determination observed in other Daphnia species were also significantly higher than those in other developmental stages. Conclusions: Our results showed that thirty-six candidate genes may involve in sex differetiation of D. similoides sinensis male, and it will provide a reference for further exploring the functional genes related to sex determination mechanism in Daphnia species. Moreover, according to previous investigations, we thought that the expression level of functional genes may be related to the development stage of organisms, and may be also affected by different Daphnia species.