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111.
112.
Jelena Rajkov Athimed El Taher Astrid Bhne Walter Salzburger Bernd Egger 《Molecular ecology》2021,30(1):274-296
Variation in gene expression contributes to ecological speciation by facilitating population persistence in novel environments. Likewise, immune responses can be of relevance in speciation driven by adaptation to different environments. Previous studies examining gene expression differences between recently diverged ecotypes have often relied on only one pair of populations, targeted the expression of only a subset of genes or used wild‐caught individuals. Here, we investigated the contribution of habitat‐specific parasites and symbionts and the underlying immunological abilities of ecotype hosts to adaptive divergence in lake–river population pairs of the cichlid fish Astatotilapia burtoni. To shed light on the role of phenotypic plasticity in adaptive divergence, we compared parasite and microbiota communities, immune response, and gene expression patterns of fish from natural habitats and a lake‐like pond set‐up. In all investigated population pairs, lake fish were more heavily parasitized than river fish, in terms of both parasite taxon composition and infection abundance. The innate immune response in the wild was higher in lake than in river populations and was elevated in a river population exposed to lake parasites in the pond set‐up. Environmental differences between lake and river habitat and their distinct parasite communities have shaped differential gene expression, involving genes functioning in osmoregulation and immune response. Most changes in gene expression between lake and river samples in the wild and in the pond set‐up were based on a plastic response. Finally, gene expression and bacterial communities of wild‐caught individuals and individuals acclimatized to lake‐like pond conditions showed shifts underlying adaptive phenotypic plasticity. 相似文献
113.
114.
Renate Hochscheid Sven Heinrichs Stephan Kranz Holger Garn Bernd Müller 《Free radical research》2013,47(7):759-767
The lung is protected against oxidative stress by a variety of antioxidants and type II pneumocytes seem to play an important role in antioxidant defense. Previous studies have shown that inhalation of NO2 results in acute and chronic lung injury. How the expression and enzyme activity of antioxidant enzymes are influenced in type II cells of different inflammatory stages has yet not been studied. To elucidate this question, we exposed rats to 10 ppm NO2 for 3 or 20 days to induce acute or chronic lung injury. From these and air-breathing rats, type II pneumocytes were isolated. The mRNA expression and protein content of CuZnSOD and MnSOD as well as total SOD-specific enzyme activity were determined. For the acute lung injury (3 d NO2), the expression of CuZnSOD mRNA was significantly increased, while MnSOD expression was significantly reduced after 3 days of NO 2 exposure. For the chronic lung injury (20 d NO2), CuZnSOD expression was still enhanced, while MnSOD expression was comparable to control. In parallel to CuZnSOD mRNA expression, the protein amount was significantly increased in acute and chronic lung injury however MnSOD protein content exhibited no intergroup differences. Total SOD enzyme activity showed a significant decrease after 3 days of NO2 exposure and was similar to control after 20 days. We conclude that during acute and chronic lung injury in type II pneumocytes expression and protein synthesis of CuZnSOD and MnSOD are regulated differently. 相似文献
115.
Hereditary channelopathies, that is, mutations in channel genes that alter channel function
and are causal for the pathogenesis of the disease, have been described for several members
of the transient receptor potential channel family. Mutations in the TRPV4 gene,
encoding a polymodal Ca2+ permeable channel, are causative for several human
diseases, which affect the skeletal system and the peripheral nervous system, with highly
variable phenotypes. In this review, we describe the phenotypes of TRPV4 channelopathies and
overlapping symptoms. Putative mechanisms to explain the puzzle, and how mutations in the
same region of the channel cause different diseases, are discussed and experimental
approaches to tackle this surprising problem are suggested. 相似文献
116.
Markus W. Gerrnann James M. Aramini Bernd W. Kalisch Richard T. Pon Johan H. van de Sande 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1481-1485
Abstract Oligodeoxynucleotides that possess alpha anomeric nucleotides and polarity reversals show promise for application in the area of antisense therapy. Here we provide a survey of the spectroscopic, thermodynamic, and enzymatic techniques used in our laboratories to investigate model systems containing such unnatural features with the ultimate goal of designing a new class of more potent and effective antisense therapeutics. 相似文献
117.
Marcel Brokbartold Erwin J. M. Temminghoff Liping Weng Bernd Marschner 《Soil & Sediment Contamination》2013,22(8):839-855
Red lead (Pb3O4) has been extensively used in the past in anti-corrosion paints for the protection of steel constructions such as electricity pylons or bridges. Until recently, little has been known about the behavior of these Pb compounds in soils. Therefore, three pylon soils and six red lead anti-corrosion paints were characterized in terms of solubility, Pb mineral composition, extractability, sorption and desorption, and the chemical speciation of Pb in soil extracts. The pylon soils were characterized by moderate total Pb concentrations (≈700 mg kg?1), while NH4NO3 extractable Pb was exceptionally high (up to 15% of total Pb). In soil extracts, the free Pb2+ fraction ranged from 33 to 81% of total soluble Pb. The equilibrium concentration of Pb derived from Pb3O4 in ultra-pure water reached 68.5 mg L?1. This high solubility explains the observed high extractability in soils and contradicts earlier reports of much lower water solubilities of the compound. 相似文献
118.
The lysosomal membrane was thought for a long time to primarily act as a physical barrier separating the luminal acidic milieu from the cytoplasmic environment. Meanwhile, it has been realized that unique lysosomal membranes play essential roles in a number of cellular events ranging from phagocytosis, autophagy, cell death, virus infection to membrane repair. This review provides an overview about the most interesting emerging functions of lysosomal membrane proteins and how they contribute to health and disease. Their importance is exemplified by their role in acidification, transport of metabolites and ions across the membrane, intracellular transport of hydrolases and the regulation of membrane fusion events. Studies in patient cells, non‐mammalian model organisms and knockout mice contributed to our understanding of how the different lysosomal membrane proteins affect cellular homeostasis, developmental processes as well as tissue functions. Because these proteins are central for the biogenesis of this compartment they are also considered as attractive targets to modulate the lysosomal machinery in cases where impaired lysosomal degradation leads to cellular pathologies. We are only beginning to understand the complex composition and function of these proteins which are tightly linked to processes occurring throughout the endocytic and biosynthetic pathways. 相似文献
119.
To investigate potential differences in stone composition with regard to the type of Primary Hyperoxaluria (PH), and in relation to the patient’s medical therapy (treatment naïve patients versus those on preventive medication) we examined twelve kidney stones from ten PH I and six stones from four PH III patients. Unfortunately, no PH II stones were available for analysis. The study on this set of stones indicates a more diverse composition of PH stones than previously reported and a potential dynamic response of morphology and composition of calculi to treatment with crystallization inhibitors (citrate, magnesium) in PH I. Stones formed by PH I patients under treatment are more compact and consist predominantly of calcium-oxalate monohydrate (COM, whewellite), while calcium-oxalate dihydrate (COD, weddellite) is only rarely present. In contrast, the single stone available from a treatment naïve PH I patient as well as stones from PH III patients prior to and under treatment with alkali citrate contained a wide size range of aggregated COD crystals. No significant effects of the treatment were noted in PH III stones. In disagreement with findings from previous studies, stones from patients with primary hyperoxaluria did not exclusively consist of COM. Progressive replacement of COD by small COM crystals could be caused by prolonged stone growth and residence times in the urinary tract, eventually resulting in complete replacement of calcium-oxalate dihydrate by the monohydrate form. The noted difference to the naïve PH I stone may reflect a reduced growth rate in response to treatment. This pilot study highlights the importance of detailed stone diagnostics and could be of therapeutic relevance in calcium-oxalates urolithiasis, provided that the effects of treatment can be reproduced in subsequent larger studies. 相似文献
120.
Judith Enders Matthias Rief Elke Zimmermann Patrick Asbach Gerd Diederichs Christoph Wetz Eberhard Siebert Moritz Wagner Bernd Hamm Marc Dewey 《PloS one》2013,8(12)