Project description:Corals in nearshore marine environments are increasingly exposed to reduced water quality, which is the major local threat to coral reefs in Hawaii. Corals surviving in such conditions may have adapted to withstand sedimentation, pollutants, and other environmental stressors. Lobe coral (Porites lobata) populations from Maunalua Bay, Hawaii showed clear genetic differentiation along with distinct cellular protein expressions between the 'polluted, high-stress' nearshore site and the 'low-stress' offshore site. To understand the driving force of the observed genetic partitioning, reciprocal transplant and common-garden experiments were conducted using the nearshore and offshore colonies of P. lobata from Maunalua Bay to assess phenotypic differences between the two coral populations. Stress-related physiological and molecular responses were compared between the two populations. Proteomic responses highlighted the inherent differences in the cellular metabolic state and activities between the two populations under the same environmental conditions; nearshore corals did not significantly alter their proteome between the sites, while offshore corals responded to the nearshore transplantation with increased abundances of proteins associated with detoxification, antioxidant, and various metabolic processes. The response differences across multiple phenotypes suggest that the observed genetic partitioning was likely due to local adaptation.
Project description:An adult P. rus colony was imported from Indonesia following the CITES protocols (Permit number 14846/IV/SATS-LN/2007) and kept in the Animal Facilities of the Justus Liebig University, Giessen. The colony was maintained in a circulating artificial seawater system at approximately 26 °C with 20-40 µmol photons m-2s-1 (T5 light) of photosynthetically active radiation on a 10:14 h light-dark cycle. A fragment of approx. 9 cm2 was separated from the colony and used as a source of tissue for hologenomic DNA/RNA isolation. Tissue was removed by scraping the fragment´s surface with a sterilized razor blade.
Project description:The evolution of brain complexity correlates with an increased expression of long, non-coding (lnc) RNAs in neuronal tissues. Although prominent examples illustrate the potential of lncRNAs to scaffold and target epigenetic regulators to chromatin loci, only few cases have been described to function during neurogenesis. We present a first functional characterization of the lncRNA LINC01322, which we term RUS for 'RNA upstream of Slitrk3'. The RUS gene is well conserved in mammals by sequence and synteny next to the neurodevelopmental gene Slitrk3. RUS is exclusively expressed in neural cells and its expression increases along with neuronal markers during neuronal differentiation of mouse embryonic cortical neural stem cells. Depletion of RUS locks neuronal precursors in an intermediate state towards neuronal differentiation, with arrested cell cycle and increased apoptosis. RUS associates with chromatin in the vicinity of genes involved in neurogenesis, most of which change their expression upon RUS depletion. The identification of a range of epigenetic regulators as specific RUS interactors suggests that the lncRNA may mediate gene activation and repression in a highly context-dependent manner.