Spatial Distribution of Cryptic Species Diversity in European Freshwater Amphipods (Gammarus fossarum) as Revealed by Pyrosequencing

In order to understand and protect ecosystems, local gene pools need to be evaluated with respect to their uniqueness. Cryptic species present a challenge in this context because their presence, if unrecognized, may lead to serious misjudgement of the distribution of evolutionarily distinct genetic entities. In this study, we describe the current geographical distribution of cryptic species of the ecologically important stream amphipod Gammarus fossarum (types A, B and C). We use a novel pyrosequencing assay for molecular species identification and survey 62 populations in Switzerland, plus several populations in Germany and eastern France. In addition, we compile data from previous publications (mainly Germany). A clear transition is observed from type A in the east (Danube and Po drainages) to types B and, more rarely, C in the west (Meuse, Rhone, and four smaller French river systems). Within the Rhine drainage, the cryptic species meet in a contact zone which spans the entire G. fossarum distribution range from north to south. This large-scale geographical sorting indicates that types A and B persisted in separate refugia during Pleistocene glaciations. Within the contact zone, the species rarely co-occur at the same site, suggesting that ecological processes may preclude long-term coexistence. The clear phylogeographical signal observed in this study implies that, in many parts of Europe, only one of the cryptic species is present

Modellhafte Erarbeitung eines oekologisch begruendeten Sanierungskonzeptes kleiner Fliessgewaesser am Beispiel der Hunte. T. 5.2 Aquatische Fauna II (Crustaceen, Odonaten, Mollusken) Materialien. Abschlussbericht

Available from TIB Hannover: QN 116(5.2) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Modellhafte Erarbeitung eines oekologisch begruendeten Sanierungskonzeptes kleiner Fliessgewaesser am Beispiel der Hunte. T. 5.1 Aquatische Fauna II (Crustaceen, Odonaten, Mollusken) Text. Abschlussbericht

Available from TIB Hannover: QN 116(5.1) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Neurotoxine und Neuroprotektion. Teilprojekt: Chloral-abgeleitete endogen auftretende Neurotoxine: Synthese, Analytik, in-vivo-Entstehung und moegliche Induktion neurodegenerativer Erkrankungen Abschlussbericht

Aim of the project was to elucidate the role of oxidative stress and of exogenous toxins in Parkinson's disease. It could be shown in pm-studies that GSH is reduced and that there is a further decline in the processing stages, while iron increases. An increase of 8-hydroxy-2-desoxyguanosin indicates that DNA undergoes oxidation. Intranigral/intrastriatal administration of iron in rats shows progressive loss of DA, DOPAC, HVA and loss of neutrons in the SN indicating iron-induced oxidative damage. In platelets of PC patients a deficit of coenzymen Q-10 shows disturbance of the electron-transport system at a time when respiratory chain enzymes and MAO-B are not changed. In analogy to MPTP/MPP"+ a cell destructing action of TaClo and N-CH_3-TaClo could be shown (TH-IR reduced in SN of rats, toxicity at the glial level, reduced DA- and GABA-uptake, release of LDH). TaClo and several of its analog compounds are protein blocker of the respiratory chain, especially of complex I. In vivo-studies in rats after chronic TaClo administration have demonstrated changes in respiratory chain enzymes which will be studied in detail in upcoming experimental trials. (orig.)SIGLEAvailable from TIB Hannover: F99B1369 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman

Transcriptome analysis reveals link between proteasomal and mitochondrial pathways in Parkinson's disease.

There is growing evidence that dysfunction of the mitochondrial respiratory chain and failure of the cellular protein degradation machinery, specifically the ubiquitin-proteasome system, play an important role in the pathogenesis of Parkinson's disease. We now show that the corresponding pathways of these two systems are linked at the transcriptomic level in Parkinsonian substantia nigra. We examined gene expression in medial and lateral substantia nigra (SN) as well as in frontal cortex using whole genome DNA oligonucleotide microarrays. In this study, we use a hypothesis-driven approach in analysing microarray data to describe the expression of mitochondrial and ubiquitin-proteasomal system (UPS) genes in Parkinson's disease (PD). Although a number of genes showed up-regulation, we found an overall decrease in expression affecting the majority of mitochondrial and UPS sequences. The down-regulated genes include genes that encode subunits of complex I and the Parkinson's-disease-linked UCHL1. The observed changes in expression were very similar for both medial and lateral SN and also affected the PD cerebral cortex. As revealed by "gene shaving" clustering analysis, there was a very significant correlation between the transcriptomic profiles of both systems including in control brains. Therefore, the mitochondria and the proteasome form a higher-order gene regulatory network that is severely perturbed in Parkinson's disease. Our quantitative results also suggest that Parkinson's disease is a disease of more than one cell class, i.e. that it goes beyond the catecholaminergic neuron and involves glia as well