Project description:In order to identify gene expression difference between marine and freshwater stickleback populations, we compared the transcriptomes of seven adult tissues (eye, gill, heart, hypothalumus, liver, pectoral muscle, telencephalon) between a marine population sampled from the mouth of the Little Campbell river in British Columbia (LITC) and a freshwater population (Fishtrap Creek, FTC) from northern Washington. For each population, the sampled individuals were the lab-reared progeny of a single pair of wild-caught parents. Four to five fish from each population were used as biological replicates for each of the seven tissues. For each population, the sampled individuals were the lab-reared progeny of a single pair of wild-caught parents. All fish were of similar age and were raised in the same aquarium (salinity: 3.5 ppt), with a plastic divider separating the marine and freshwater groups. One male and four females were sampled from each population. Microarray experiments were performed in a 2-color format on custom Agilent arrays: experimental RNA samples were labeled with Cy5, and the common reference RNA sample was labeled with Cy3. The reference RNA was total RNA isolated from a large number of 7-day-post-hatch embryos from the freshwater population of Bear Paw Lake, Alaska (BEPA). One technical replicate was used for each array, and one of the hypothalamus samples (Hyp_FTC#3) was excluded from further analysis due to poor quality indicators. FTC#1 liver and LITC#2 pectoral muscle samples did not yield RNA of sufficient quality for the microarray experiment, and were also excluded from hybridization.

2011-12-30 | E-GEOD-34783 | biostudies-arrayexpress

Transcriptional analysis of freshwater bacterium Polynucleobacter asymbioticus strain QLW-P1DMWA-1T

Project description:Polynucleobacter asymbioticus strain QLW-P1DMWA-1T represents a group of highly successful heterotrophic planktonic bacteria, dwelling in freshwater systems (lakes, ponds, and streams) across all climatic zones and across all continents. This includes habitats characterised by strongly fluctuating environmental conditions. So the experiments were designed to mimick winter and summer scenarios with additional impact of UV irradiation. Comparative transcriptomic studies were conducted to analyse gene-expression levels in contrasting experimental conditions. Overall, molecular candidates were revealed that may contribute in rapid acclimatisation of this strain in their immediate environment.

2017-10-31 | GSE98129 | GEO

Marine and freshwater three-spined stickleback (Gasterosteus aculeatus) gene expression differences

2011-12-30 | GSE34783 | GEO

Epigenetic adaptation of stickleback to sea and freshwater conditions: RNA-seq

Project description:Three-spined stickleback (Gasterosteus aculeatus) represents a convenient model to study microevolution - adaptation to freshwater environment. While genetic adaptations to freshwater are well-studied, epigenetic adaptations attracted little attention. In this work, we investigated the role of DNA methylation in the adaptation of marine stickleback population to freshwater conditions. DNA methylation profiling was performed in marine and freshwater populations of sticklebacks, as well as in marine sticklebacks placed into freshwater environment and freshwater sticklebacks placed into seawater. For the first time, we demonstrated that genes encoding ion channels kcnd3, cacna1fb, gja3 are differentially methylated between marine and freshwater populations. We also showed that after placing marine stickleback into fresh water, its DNA methylation profile partially converges to the one of a freshwater stickleback. This suggests that immediate epigenetic response to freshwater conditions can be maintained in freshwater population. Interestingly, we observed enhanced epigenetic plasticity in freshwater sticklebacks that may serve as a compensatory regulatory mechanism for the lack of genetic variation in the freshwater population. Some of the regions that were reported previously to be under selection in freshwater populations also show differential methylation. Thus, epigenetic changes might represent a parallel mechanism of adaptation along with genetic selection in freshwater environment. This is the RNA-seq experiment, DNA methylation data (bisulfite-seq) is provided under accession number GSE82310.

2021-11-03 | GSE186925 | GEO

Defined diets for freshwater planarians.

Project description: Not available

| S-EPMC8758798 | biostudies-literature