Project description:<p>Understanding biogeochemical conversions of dissolved organic matter (DOM) in aquifers is paramount for the effective management of groundwater supplies. On its passage through the critical zone, DOM is subject to biogeochemical conversions and therefore carries cross-habitat information useful for monitoring and predicting the stability of groundwater ecosystem services. Groundwater metabolomics assesses this information. However, challenges arise from insufficient knowledge on groundwater metabolite composition and dynamics, and the necessity to maintain analytical conditions for long-term monitoring. We explored fractured sedimentary bedrock by 5-year untargeted metabolomics monitoring for oxic perched and anoxic phreatic sites along a hillslope recharge area, to evaluate DOM as groundwater tracer. Dimension reduction by principal component analysis revealed that metabolome dissimilarities between distant wells coincide with transient cross-stratal flow indicated by groundwater levels and environmental tracers. The metabolome was highly variable lacking seasonal patterns, and did not segregate by geographic location of sampling wells thus ruling out surface vegetation or (agricultura) land use as driving factor. The metabolome time series provide detailed insights into subsurface responses to recharge dynamics. Metabolomics monitoring provides information on groundwater flows, and allows concluding about below ground ecology and water quality evolution, required to understand the impact of interannual wet-dry cycles.</p><p><br></p><p>This study is an extension of groundwater monitoring untargeted <strong>MS1 data </strong>previously published in <a href='https://www.ebi.ac.uk/metabolights/MTBLS3450' rel='noopener noreferrer' target='_blank'><strong>MTBLS3450</strong></a> and <a href='https://www.ebi.ac.uk/metabolights/editor/MTBLS8433' rel='noopener noreferrer' target='_blank' style='color: currentcolor;'><strong>MTBLS8433</strong></a></p>
Project description:The pervasiveness of gene expression variation and its contribution to phenotypic variation and evolution is well known. This gene expression variation is context dependent, with differences in regulatory architecture often associated with intrinsic and environmental factors, and is modulated by regulatory elements that can act in cis (linked) or in trans (unlinked) relative to the genes they affect. So far, little is known about how this genetic variation affects the evolution of regulatory architecture among closely related tissues during population divergence. To address this question, we analyzed gene expression in the midgut, hindgut, and Malpighian tubule as well as microbiome composition in the two gut tissues in four Drosophila melanogaster strains and their F1 hybrids from two divergent populations: one from the derived, European range and one from the ancestral, African range. In both the transcriptome and microbiome data, we detected extensive tissue- and genetic background-specific effects, including effects of genetic background on overall tissue specificity. Tissue-specific effects were typically stronger than genetic background-specific effects, although the two gut tissues were not more similar to each other than to the Malpighian tubules. An examination of allele specific expression revealed that, while both cis and trans effects were more tissue-specific in genes expressed differentially between populations than genes with conserved expression, trans effects were more tissue-specific than cis effects. Despite there being highly variable regulatory architecture, this observation was robust across tissues and genetic backgrounds, suggesting that the expression of trans variation can be spatially fine-tuned as well as or better than cis variation during population divergence and yielding new insights into cis and trans regulatory evolution.
Project description:Bacterial diversity , community composition (16S rRNA), odor compounds and fluorescence components of pipe biofilms from drinking water distribution systems