Project description:Evolutionary alterations to cis-regulatory sequences are likely to cause adaptive phenotypic complexity, through orchestrating changes in cellular proliferation, identity and communication. For non-model organisms with adaptive key-innovations, patterns of regulatory evolution have been predominantly limited to targeted sequence-based analyses. Chromatin-immunoprecipitation with high-throughput sequencing (ChIP-seq) is a technology that has only been used in genetic model systems and is a powerful experimental tool to screen for active cis-regulatory elements. Here, we show that it can also be used in ecological model systems and permits genome-wide functional exploration of cis-regulatory elements. As a proof of concept, we use ChIP-seq technology in adult fin tissue of the cichlid fish Oreochromis niloticus to map active promoter elements, as indicated by occupancy of trimethylated Histone H3 Lysine 4 (H3K4me3). The fact that cichlids are one of the most phenotypically diverse and species-rich families of vertebrates could make them a perfect model system for the further in-depth analysis of the evolution of transcriptional regulation. examination of H3K4me3 in adult fin tissue of the Nile tilapia (Oreochromis niloticus)
Project description:Buffering of deleterious mutations by molecular chaperones and degradation of aberrant proteins by quality control systems are both major factors that can impact the mutational landscape available to a client protein. The impacts of the proteostasis network on protein evolution are not limited to just endogenous clients, but can also shape the mutational landscapes accessible to rapidly evolving viral proteins. Here, we test the hypothesis that the composition of the host cell’s endoplasmic reticulum (ER) proteostasis network shapes the evolution of RNA viruses by focusing on human immunodeficiency virus-1 envelope (Env), a membrane glycoprotein that folds and matures in the host cell’s secretory pathway. We apply chemical genetic methods to activate the IRE1-XBP1s and/or the ATF6 transcriptional arms of the unfolded protein response in a stress-independent manner. We then quantitatively assess the impact of the resulting altered host cell ER proteostasis environments on the relative enrichment of all Env single amino acid substitutions using deep mutational scanning. We find that upregulation of host ER proteostasis factors globally reduces the mutational tolerance of HIV-1 Env, particularly upon induction of the IRE1-XBP1s transcriptional arm of the UPR. The effects of ATF6 activation are less global, but still significant at particular Env sites. The impact of the XBP1s-induced ER proteostasis environment is disparate for diverse structural elements of Env. Conserved, functionally important regions generally exhibit the largest decreases in mutational tolerance upon XBP1s activation. In contrast, specific regions of Env, including regions targeted by broadly neutralizing antibodies, display greatly enhanced mutational tolerance when XBP1s is activated. Altogether, these data reveal a new set of host factors that specifically shape the mutational space accessible to HIV Env and, more generally, provide compelling evidence that UPR-regulated proteostasis mechanisms play critical roles in membrane protein evolution.
Project description:These data provide a basis for exploration of gene expression differences between physiologically diverse accessions of Arabidopsis thaliana. Recent studies have documented remarkable genetic variation among Arabidopsis thaliana accessions collected from diverse habitats and across its geographical range. Of particular interest are accessions with putatively locally adapted phenotypes M-bM-^@M-^S i.e., accessions with attributes that are likely adaptive under the climatic or habitat conditions of their sites of origin. These genotypes are especially valuable as they may provide insight into the genetic basis of adaptive evolution as well as allow the discovery of genes of ecological importance. Therefore we studied the physiology, genome content and gene expression of 18 physiologically diverse accessions. The gene expression studies were conducted under two levels of soil moisture and accompanied by physiological measurements to characterize early responses to soil moisture deficit. The basic experimental design involves 18 accessions crossed with two environmental levels (well-watered soil and mild soil drying) and 3 biological replicates per accession/treatment combination.
Project description:Dynamic nuclear SUMO modifications play essential roles in orchestrating cellular responses to proteotoxic stress, DNA damageand DNA virus infections. Here, we describe the host SUMOylation response to the nuclear-replicating RNA pathogen, influenz A virus. Using quantitative proteomics to compare SUMOylation responses to various stresses (including heat-shock), we reveal that influenza A virus infection causes unique re-targeting of SUMO1 and SUMO2 to a diverse range of host proteins involved in transcription, mRNA processing, RNA quality control and DNA damage repair. This global characterization of influenza virus-triggered SUMO remodeling provides a proteomic resource to understand host nuclear SUMOylation responses to infection.
Project description:These data provide a basis for exploration of gene expression differences between physiologically diverse Spring annual accessions of Arabidopsis thaliana. Recent studies have documented remarkable genetic variation among Arabidopsis thaliana accessions collected from diverse habitats and across its geographical range. Of particular interest are accessions with putatively locally adapted phenotypes M-bM-^@M-^S i.e., accessions with attributes that are likely adaptive under the climatic or habitat conditions of their sites of origin. These genotypes are especially valuable as they may provide insight into the genetic basis of adaptive evolution as well as allow the discovery of genes of ecological importance. Therefore we studied the physiology, genome content and gene expression of 18 physiologically diverse accessions. The gene expression studies were conducted under two levels of soil moisture and accompanied by physiological measurements to characterize early responses to soil moisture deficit. The basic experimental design involves 10 accessions crossed with two environmental levels (well-watered soil and mild soil drying) and 3 biological replicates per accession/treatment combination.
Project description:Evolutionary alterations to cis-regulatory sequences are likely to cause adaptive phenotypic complexity, through orchestrating changes in cellular proliferation, identity and communication. For non-model organisms with adaptive key-innovations, patterns of regulatory evolution have been predominantly limited to targeted sequence-based analyses. Chromatin-immunoprecipitation with high-throughput sequencing (ChIP-seq) is a technology that has only been used in genetic model systems and is a powerful experimental tool to screen for active cis-regulatory elements. Here, we show that it can also be used in ecological model systems and permits genome-wide functional exploration of cis-regulatory elements. As a proof of concept, we use ChIP-seq technology in adult fin tissue of the cichlid fish Oreochromis niloticus to map active promoter elements, as indicated by occupancy of trimethylated Histone H3 Lysine 4 (H3K4me3). The fact that cichlids are one of the most phenotypically diverse and species-rich families of vertebrates could make them a perfect model system for the further in-depth analysis of the evolution of transcriptional regulation.
Project description:BONCAT was adapted and tested as a method for directly quantifying viral production in the ocean. To confirm the successful transfer of host-associated HPG-labeled proteins or peptides into marine viruses, we conducted an independent suite of proteomic experiments with cultured systems to directly assess the production of HPG-labeled viral proteins. We used including Emiliania huxleyi strain CCMP374 and its ~200nm coccolithovirus EhV207 as well as E. coli and its ~50 nm virus T7 as virus-host model systems. These specific model systems were chosen because they represent a range of viral particle sizes and their infection dynamics are well characterized. E. huxleyi/EhV207 also represents an ecologically relevant marine virus-host pair.
Project description:These data provide a basis for exploration of gene expression differences between physiologically diverse accessions of Arabidopsis thaliana. Recent studies have documented remarkable genetic variation among Arabidopsis thaliana accessions collected from diverse habitats and across its geographical range. Of particular interest are accessions with putatively locally adapted phenotypes – i.e., accessions with attributes that are likely adaptive under the climatic or habitat conditions of their sites of origin. These genotypes are especially valuable as they may provide insight into the genetic basis of adaptive evolution as well as allow the discovery of genes of ecological importance. Therefore we studied the physiology, genome content and gene expression of 18 physiologically diverse accessions. The gene expression studies were conducted under two levels of soil moisture and accompanied by physiological measurements to characterize early responses to soil moisture deficit.
Project description:Two genetic selection systems that couple metabolite hydroxylation or methylation of small molecules to growth of Escherichia coli are presented in this study. One system targets pterin-dependent hydroxylation (tBPt) while another focuses on S-adenosylmethionine-dependent methylation (SAM). Using adaptive laboratory evolution with growth selection, these two systems are demonstrated to not only achieve in vivo directed evolution of enzymes involved in human hormone biosynthesis but also reveal non-intuitive host factors that elude existing synthetic biology approaches. Raw sequencing data for the relevant strains generated in this study are presented here.
Project description:These data provide a basis for exploration of gene expression differences between physiologically diverse Spring annual accessions of Arabidopsis thaliana. Recent studies have documented remarkable genetic variation among Arabidopsis thaliana accessions collected from diverse habitats and across its geographical range. Of particular interest are accessions with putatively locally adapted phenotypes – i.e., accessions with attributes that are likely adaptive under the climatic or habitat conditions of their sites of origin. These genotypes are especially valuable as they may provide insight into the genetic basis of adaptive evolution as well as allow the discovery of genes of ecological importance. Therefore we studied the physiology, genome content and gene expression of 18 physiologically diverse accessions. The gene expression studies were conducted under two levels of soil moisture and accompanied by physiological measurements to characterize early responses to soil moisture deficit.