Project description:We performed a RNA immunoprecipitations experiments using gfp-specific antibodies to precipitate gfp-tagged La proteins from from gfp-La wild type and sumoylation deficient La mutant (K41/200R) cells and found that specific mRNAs are preferentially enriched gfp-La wild type RIPs when compared to sumoylation deficient La mutant (K41/200R) RIPs.
Project description:Southern California (USA) populations of the intertidal marine snail Chlorostoma (formerly Tegula) funebralis are generally exposed to higher air and water temperatures than northern California populations. Previous studies have shown that southern populations are more tolerant of heat stress than northern populations. To assess the potential role of gene regulation in these regional differences, we examined transcriptome responses to thermal stress in two southern and two northern populations of C. funebralis. Snails from the four populations were acclimated to a common lab environment, exposed to a heat stress representative of natural low tide conditions, and then analyzed using RNA-Seq to characterize changes in gene expression associated with stress and differences in expression across geographic regions. Changes in expression following stress were dominated by genes involved in apoptosis, the inflammatory response, response to mis and unfolded proteins, and ubiquitination of proteins. Heat shock proteins (Hsps) were up-regulated in both northern and southern populations. However, while the magnitude of the response was significantly greater in northern populations for the majority of Hsp70s, the southern populations showed a greater up-regulation for roughly half of the Hsp40s, which are co-chaperones for Hsp70s. Differential expression analysis of the control versus treatment genes in the northern and southern populations respectively revealed that 56 genes, many involved in the inflammation and immune response, responded to heat stress only in the northern populations. Moreover, several of the molecular chaperones and antioxidant genes that were not differentially expressed in the southern populations instead showed higher constitutive expression under control conditions compared to the northern populations. The expression levels of some of these constitutive genes such as superoxide dismutase were also found to positively correlate with survival following heat stress. This suggests that expression of these genes has evolved a degree of “frontloading” that may contribute to the higher thermal tolerance of southern populations.
Project description:<p>Coral reef ecosystems are incredibly diverse marine biomes that rely on nutrient cycling by microorganisms to sustain high productivity in generally oligotrophic regions of the ocean. Understanding the composition of extracellular reef metabolites in seawater, the small organic molecules that serve as the currency for microorganisms, may provide insight into benthic-pelagic coupling as well as the complexity of nutrient cycling in coral reef ecosystems. Jardines de la Reina, Cuba is an ideal environment to examine extracellular metabolites across protected and high-quality reefs. Here, we used metabolic methods to quantify specific known metabolites of interest (targeted approach) and to survey trends in metabolite feature composition (untargeted approach) from surface and reef depth (6 – 14 m) seawater overlying forereefs in Jardines de la Reina. We found that untargeted metabolite feature composition was fairly similar between reef depth and surface seawater across the archipelago, corresponding with other biogeochemical and physicochemical measurements and suggesting that environmental conditions were largely homogenous across forereefs within Jardines de la Reina. Additionally, we quantified 32 of 53 detected metabolites, including amino acids, nucleosides, vitamins, and other metabolic intermediates. Two of the quantified metabolites, riboflavin and 5ʹ-methylthioadenosine (MTA), displayed interesting trends by depth and geographic location, respectively. Riboflavin concentrations were higher in reef depth compared to surface seawater, suggesting that riboflavin may be produced by reef organisms at depth and degraded in the surface through photochemical oxidation. 5ʹ-MTA concentrations increased significantly within the central region of the archipelago, displaying biogeographic patterns that warrant further investigation. Here we lay the groundwork for future investigations of variations in metabolite composition across reefs, sources and sinks of reef metabolites, and changes in metabolites over environmental, temporal, and reef health gradients.</p>
Project description:Southern California (USA) populations of the intertidal marine snail Chlorostoma (formerly Tegula) funebralis are generally exposed to higher air and water temperatures than northern California populations. Previous studies have shown that southern populations are more tolerant of heat stress than northern populations. To assess the potential role of gene regulation in these regional differences, we examined transcriptome responses to thermal stress in two southern and two northern populations of C. funebralis. Snails from the four populations were acclimated to a common lab environment, exposed to a heat stress representative of natural low tide conditions, and then analyzed using RNA-Seq to characterize changes in gene expression associated with stress and differences in expression across geographic regions. Changes in expression following stress were dominated by genes involved in apoptosis, the inflammatory response, response to mis and unfolded proteins, and ubiquitination of proteins. Heat shock proteins (Hsps) were up-regulated in both northern and southern populations. However, while the magnitude of the response was significantly greater in northern populations for the majority of Hsp70s, the southern populations showed a greater up-regulation for roughly half of the Hsp40s, which are co-chaperones for Hsp70s. Differential expression analysis of the control versus treatment genes in the northern and southern populations respectively revealed that 56 genes, many involved in the inflammation and immune response, responded to heat stress only in the northern populations. Moreover, several of the molecular chaperones and antioxidant genes that were not differentially expressed in the southern populations instead showed higher constitutive expression under control conditions compared to the northern populations. The expression levels of some of these constitutive genes such as superoxide dismutase were also found to positively correlate with survival following heat stress. This suggests that expression of these genes has evolved a degree of M-bM-^@M-^\frontloadingM-bM-^@M-^] that may contribute to the higher thermal tolerance of southern populations. mRNA profiles of northern and southern California heat-stressed and control C. funebralis were generated by 100bp paired end sequencing, in duplicate, using Illumina HiSeq2000.
Project description:Global warming is causing plastic and evolutionary changes in the phenotypes of ectotherms. Yet, we have limited knowledge on how the interplay between plasticity and evolution shapes thermal responses and underlying gene expression patterns. We assessed thermal reaction norm patterns across the transcriptome and identified associated molecular pathways in northern and southern populations of the damselfly Ischnura elegans. Larvae were reared in a common garden experiment at the mean summer water temperatures experienced at the northern (20 °C) and southern (24 °C) latitudes. This allowed a space-for-time substitution where the current gene expression levels at 24 °C in southern larvae are a proxy for the expected responses of northern larvae under gradual thermal evolution to the predicted 4 °C warming. Most differentially expressed genes showed fixed differences across temperatures between latitudes, suggesting that thermal genetic adaptation will mainly evolve through changes in constitutive gene expression. Northern populations also frequently showed plastic responses in gene expression to mild warming, while southern populations were much less responsive to temperature. Thermal responsive genes in northern populations showed to a large extent a pattern of genetic compensation, i.e. gene expression that was induced at 24 °C in northern populations remained at a lower constant level in southern populations, and were associated with metabolic and translation pathways. There was instead little evidence for genetic assimilation of an initial plastic response to mild warming. Our data therefore suggest that genetic compensation rather than genetic assimilation may drive the evolution of plasticity in response to mild warming in this damselfly species.
Project description:We recently identified lysine L-lactylation (KL-la) on histones that can be labelled by L-lactate, the end-product of glycolysis. KL-la has two structural isomers, namely N--(carboxyethyl) lysine (Kce) and lysine D-lactylation (KD-la), which can also be caused by metabolites associated with glycolysis. It is unknown if perturbations of glycolysis can lead to dysregulation of KD-la and Kce, in addition to KL-la. Further, current methods have a difficulty to distinguish among these isomers in cellular contexts. To investigate these questions, we first generated specific antibodies against each one of these three modifications. These reagents enable us to distinguish these three isomers. We demonstrated that KL-la, but not KD-la and Kce, is dynamically regulated by glycolysis. KD-la and Kce occur mainly when the major glycolytic pathway is blocked downstream or when the glyoxalase system is incomplete. This result was also independently confirmed by orthogonal HPLC-mass spectrometry, showing that KL-la is the predominant isomer of lactylation on cellular histones. Finally, we demonstrated that lactyl-CoA, an intermediate between L-lactate and lactylation, is dynamically regulated by glycolysis and is positively correlated with KL-la. Thus, our study clearly shows that KL-la, but not KD-la and Kce, is the major glycolytic- and the Warburg-effect associated responsive modification in cells.
Project description:Parque Nacional La Campana (PNLC) is recognized worldwide for its flora and fauna, rather than for its microbial richness. Our goal was to characterize the structure and composition of microbial communities (bacteria, archaea and fungi) and their relationship with the plant communities typical of PNLC, such as sclerophyllous forest, xerophytic shrubland, hygrophilous forest and dry sclerophyllous forest, distributed along topoclimatic variables, namely, exposure, elevation and slope. The plant ecosystems, the physical and chemical properties of organic matter and the soil microbial composition were characterized by massive sequencing (iTag-16S rRNA, V4 and ITS1-5F) from the DNA extracted from the soil surface (5 cm, n = 16). A contribution of environmental variables, particularly related to each location, is observed. Proteobacteria (35.43%), Actinobacteria (32.86%), Acidobacteria (10.07%), Ascomycota (76.11%) and Basidiomycota (15.62%) were the dominant phyla. The beta diversity (~80% in its axes) indicates that bacteria and archaea are linked to their plant categories, where the xerophytic shrub stands out with the most particular microbial community. More specifically, Crenarchaeote, Humicola and Mortierella were dominant in the sclerophyllous forest; Chloroflexi, Cyanobacteria and Alternaria in the xerophytic shrubland; Solicoccozyma in the dry sclerophyllous forest; and Cladophialophora in the hygrophilous forest. In conclusion, the structure and composition of the microbial consortia is characteristic of PNLC's vegetation, related to its topoclimatic variables, which suggests a strong association within the soil microbiome.