Project description:This SuperSeries is composed of the following subset Series: GSE29854: Daphnia magna exposed to narcotics and polar narcotics - aniline GSE29856: Daphnia magna exposed to narcotics and polar narcotics - 4-chloroaniline GSE29857: Daphnia magna exposed to narcotics and polar narcotics - 3,5-dichloroaniline GSE29858: Daphnia magna exposed to narcotics and polar narcotics - 2,3,4-trichloroaniline GSE29862: Daphnia magna exposed to narcotics and polar narcotics - ethanol GSE29864: Daphnia magna exposed to narcotics and polar narcotics - isopropanol GSE29867: Daphnia magna exposed to narcotics and polar narcotics - methanol Refer to individual Series
Project description:Polar cod (Boreogadus saida), a key arctic fish species spawning during the polar night, may be at risk for crude oil exposure during this potential sensitive life stage. This study investigates the effects of crude oil exposure on Polar cod during spawning season. Wild-caught polar cod were exposed to crude oil water accommodated fraction (WAF) (start concentrations of sum of 44 polycyclic aromatic hydrocarbon (sum 44 PAHs) at 12.5 μg/L) from pre-spawning to post-spawning. The exposure system consisted of an oiled-rock-column system where running though sweater delivers WAF in the fish tank at decreasing concentrations over time. Samples were taken at three time-points (pre-spawning, spawning window, and post-spawning) and used to evaluate changes in reproductive endpoints such as gonad histology, plasma steroid hormones and sperm motility. For RNA-extraction and sequencing, liver samples from both oil-exposed and control groups of female fish (n = 5 per group) were taken at 47 days after experiment start and submitted for sequencing. RNA-seq analysis showed that hundreds of genes were differentially expressed in the liver.
Project description:Clinicians need additional metrics for predicting quality of human oocytes for IVF procedures. Human polar bodies reflect the oocyte transcript profile. Quantitation of polar body mRNAs could allow for both oocyte ranking and embryo preferences in IVF applications. The transcriptome of a polar body has never been reported, in any organism. Eight total samples. There are 2 biological replicates of the following four conditions: pooled oocytes and their sister polar bodies and a single oocyte and its sister polar body.
Project description:Clinicians need additional metrics for predicting quality of human oocytes for IVF procedures. Human polar bodies reflect the oocyte transcript profile. Quantitation of polar body mRNAs could allow for both oocyte ranking and embryo preferences in IVF applications. The transcriptome of a polar body has never been reported, in any organism.
Project description:Diatoms, the major eukaryotic phytoplankton in polar regions, are essential to sustain food webs. As such, it is fundamental to understand the physiological mechanisms and associated molecular basis of resilience to polar night of diatoms. Here, we report an integrative approach that reveals that in prolonged darkness, the cell enters a state of hypometabolism associated with reduced transcriptional activity during which no cell division occurs. Minimal energy is provided by respiration via alternative oxidase and progressive degradation of protein, carbohydrate and lipid stores. We also report internal structural changes that manifest the morphological acclimation of cells to darkness. Our results further indicate that immediately after returning to light, the majority of cells were able to use photoprotective mechanisms and resume photosynthesis. Divisions of surviving cells resumed at rates similar to those before darkness. Our study demonstrates the robustness of this species to prolonged darkness at low temperatures.
Project description:During host cell invasion, microsporidia translocate their entire cytoplasmic contents through a thin, hollow superstructure known as the polar tube. To achieve this, the polar tube transitions from a compact spring-like state inside the environmental spore to a long needle-like tube capable of longrange sporoplasm delivery. The unique mechanical properties of the building blocks of the polar tube allow for an explosive transition from compact to extended state and support the rapid cargo translocation process. The molecular and structural factors enabling this ultrafast process and the ultrastructural changes during cargo delivery remain a mystery. Here, we employ light microscopy and in situ cryo-electron tomography to visualize multiple ultrastructural states of the polar tube, allowing us to evaluate the kinetics of its germination and characterize the underlying morphological transitions. We describe a cargo-filled state with a unique ordered arrangement of microsporidian ribosomes, which cluster along the thin tube wall, and an empty post-translocation state with a reduced diameter but a thicker wall. Together with endogenous compositional information from an affinity-purified polar tube, our work provides comprehensive novel data on the infection apparatus of microsporidia and demonstrates that ribosomes are efficiently transported through polar tubes in a spiral-like parallel arrangement.