Project description:The marine bacterium Phaeobacter inhibens produces tropodithietic acid (TDA), a broad-spectrum antibiotic and anticancer agent. TDA allows P. inhibens to antagonize other bacteria, including several pathogens, and eukaryotes. Since recently antibiotics are also discussed to function as intermicrobial signals. Here we show that ~10% of the genes of P. inhibens are strongly influenced by N-acyl-homoserine lactone (AHL) mediated quorum sensing (QS), switching the bacterium’s life style from attached to free-living. In an AHL negative mutant of P. inhibens subinhibitory concentrations of TDA caused the same regulatory effect as the AHL. This demonstrates that bacteria can produce antibiotic compounds not only as weapons, but also to substitute their endogenous AHL molecule in QS. The dual function of TDA probably supports the QS system to accelerate regulatory processes and points to a so far neglected role of antibiotics at subinhibitory concentrations in the environment and in microbial interactions. Comparison of whole transcriptomes of wildytype, quorum sensing mutants (pgaI and pgaR) and pgaI grown supplemented with subinhibitory concentration of the antibiotic TDA. RNA isolated in the late exponential growth phase. 4 biological replicates investigated for each strain.
Project description:We have combined high-quality genome sequencing and RNA-sequencing data within a 17-individual, three generation family. Using these data, we have contrasted cis-acting expression, allele-specific expression and splicing quantitative trait loci (collectively termed eQTLs) within the family to eQTLs discovered within a cell-type and ethnicity-matched population sample. We identified that eQTL that exhibit larger effects in the family compared to the population are enriched for rare regulatory and splicing variants and were more likely to influence essential genes. In addition, we identify several large effect-size eQTLs within the family for genes involved in complex disease. Through analysis of eQTLs in a large family we also report the utility of non-coding genome annotation to predicting the effect of rare non-coding variants. We find that a combination of distance to the transcription start site, evolutionary constraint and epigenetic annotation is considerably more informative for predicting the consequence of rare non-coding variants than for common variants. In summary, through transcriptome analyses within a large family we are able to identify the contribution of rare non-coding variants to expression phenotypes and further demonstrate the predictive potential of diverse non-coding genome annotation for interpretation of the impact of rare non-coding variants. RNA-Sequencing of CEPH/UTAH family 1463
Project description:Plants display remarkable developmental and phenotypic plasticity in order to adapt to their environment. It has long been postulated that epigenetics plays a key role in these processes, but with one or two exceptions, solid evidence for the role of epigenetic variation in these processes is lacking. A key impediment to understanding these processes is the lack of information on the extent of epigenetic variation and how it relates to genetic and phenotypic variation in natural population, both over the lifecycle of an individual, and over evolutionary time. Here we show that genetic variants under selection in the north of Sweden appear to drive variation in DNA methylation, which in turn is highly correlated with local climate. Selective sweeps and genetic variants associated with adaptation to the local environment have previously been identified within the Swedish Arabidopsis population. Our finding that they harbour variants responsible for climate associated epigenetic variation strongly supports the role of epigenetic processes in local adaptation. These findings provide a basis for further dissecting the role of epigenetics in local adaptation at the molecular level Bisulfite sequencing of 113 F2 crosses between T550 and Brosarp-11-135.
Project description:We used whole-genome microarrays to identify the global transcriptional changes during biofilm dispersal and also to investigate the molecular mechanism that regulating biofilm dispersal. Overall design: S. mutans biofilms at different dispersal stages were collected for microarray analysis
Project description:The epigenomics approaches presented here provide the first comprehensive study of the patterns and heritability of methylation variants in a complex genetic population over multiple generations paving the way for understanding how methylation variants contribute to phenotypic variation. MethylC-Seq and RNA-Seq data collected from Glycine max leaves of two parental lines of a RIL population and two individual RILs. Additionally gDNA-Seq was performed on the two parental lines [SRA060034].