Project description:Investigation of mRNA expression (using HiSeq 2500) in response to treatment of Daphnia magna to pyriproxyfen, wetland water, or stormwater samples.
Project description:To unravel complex dynamics of environmental disturbance and microbial metabolic activities, we set up laboratory microcosms to investigate the effects of SO42- and O2 alone or in combination on microbial activities and interactions, as well as the resulting fate of carbon within wetland soil. We used proteogenomics to characterize the biochemical and physiological responses of microbial communities to individual perturbations and their combined effects. Stoichiometric models were employed to deconvolute carbon exchanges among the main functional guilds. These findings can contribute to the development of mechanistic models for predicting greenhouse gas emissions from wetland ecosystems under various climate change scenarios.
Project description:We investigated the morphological roots decisions of Arabidopsis in a NO3- heterogeneous medium. To do so, we used the Split-Root System which is an experimental set up to assess root decisions in nutrient heterogeneous medium. Split-root plants have been subjected to three different treatments. ‘Control KNO3’ plants received KNO3 on both sides of the root system (C.NO3) and ‘Control KCl’ plants received KCl on both sides (C.KCl) as a nitrogen deprivation treatment. 'Split' plants received KNO3 on one side (Sp.NO3) and KCl on the other side (Sp.KCl) of the root system to assess the root decision-making in a heterogeneous environment. We observed that the total lateral roots length in the Sp.NO3 and C.KCl compartments is induced as compared to C.NO3 and Sp.KCl compartments. This corresponds to a root proliferation response in strategic territories to compensate the nitrogen deprivation. To decipher the molecular basis of this morphological root response on day 4 after the beginning of the split-root treatment, we used a transcriptomic approach on roots at 2hours, 8 hours and 2 days after the beginning of the treatment. From our microarrays data, we have identified a global set of 150 genes for which the expression pattern match with the lateral roots responses. Among them, we selected 8 early marker genes of the root decisions, which allowed us to show that the shoots and the NO3- itself are essential for the decision. Finally, we tested the role of the cytokinins phytohormones as a NO3--derived systemic signal in the root decision. Interestingly, we have demonstrated that the systemic cytokinins are involved into the decision of inducing maker genes expression and making lateral roots in the Sp.NO3 compartment specifically.
Project description:Monitoring microbial communities can aid in understanding the state of these habitats. Environmental DNA (eDNA) techniques provide efficient and comprehensive monitoring by capturing broader diversity. Besides structural profiling, eDNA methods allow the study of functional profiles, encompassing the genes within the microbial community. In this study, three methodologies were compared for functional profiling of microbial communities in estuarine and coastal sites in the Bay of Biscay. The methodologies included inference from 16S metabarcoding data using Tax4Fun, GeoChip microarrays, and shotgun metagenomics.
Project description:Expression diversity of P. ramorum isolates belonging to the NA1 clonal lineage growing on solid CV8 was examined. It was found that although all the analyzed isolates belonged to a single clonal lineage, expression patterns were distinctive between isolates originating from coast live oak and California bay laurel. Global expression patterns of 13 isolates originating from coastal live oak and California bay laurel was investigated. No biological replicates were generated. The sequenced strain Pr102 was included. Gene models Phytophthora ramorum v1.0 were used to construct NimbleGen 72K x4 custom arrays.