Landscape genomics and a common garden trial reveal adaptive differentiation to temperature across Europe in the tree species Alnus glutinosa

The adaptive potential of tree species to cope with climate change has important ecological and economic implications. Many temperate tree species experience a wide range of environmental conditions, suggesting high adaptability to new environmental conditions. We investigated adaptation to regional climate in the drought‐sensitive tree species Alnus glutinosa (Black alder), using a complementary approach that integrates genomic, phenotypic and landscape data. A total of 24 European populations were studied in a common garden and through landscape genomic approaches. Genotyping‐by‐sequencing was used to identify SNPs across the genome, resulting in 1990 SNPs. Although a relatively low percentage of putative adaptive SNPs was detected (2.86% outlier SNPs), we observed clear associations among outlier allele frequencies, temperature and plant traits. In line with the typical drought avoiding nature of A. glutinosa, leaf size varied according to a temperature gradient and significant associations with multiple outlier loci were observed, corroborating the ecological relevance of the observed outlier SNPs. Moreover, the lack of isolation by distance, the very low genetic differentiation among populations and the high intrapopulation genetic variation all support the notion that high gene exchange combined with strong environmental selection promotes adaptation to environmental cues.     

Dermal application of nitric oxide releasing acidified nitrite-containing liniments significantly reduces blood pressure in humans

Vascular ischemic diseases, hypertension, and other systemic hemodynamic and vascular disorders may be the result of impaired bioavailability of nitric oxide (NO). NO but also its active derivates like nitrite or nitroso compounds are important effector and signal molecules with vasodilating properties. Our previous findings point to a therapeutical potential of cutaneous administration of NO in the treatment of systemic hemodynamic disorders. Unfortunately, no reliable data are available on the mechanisms, kinetics and biological responses of dermal application of nitric oxide in humans in vivo. The aim of the study was to close this gap and to explore the therapeutical potential of dermal nitric oxide application. We characterized with human skin in vitro and in vivo the capacity of NO, applied in a NO-releasing acidified form of nitrite-containing liniments, to penetrate the epidermis and to influence local as well as systemic hemodynamic parameters. We found that dermal application of NO led to a very rapid and significant transepidermal translocation of NO into the underlying tissue. Depending on the size of treated skin area, this translocation manifests itself through a significant systemic increase of the NO derivates nitrite and nitroso compounds, respectively. In parallel, this translocation was accompanied by an increased systemic vasodilatation and blood flow as well as reduced blood pressure. We here give evidence that in humans dermal application of NO has a therapeutic potential for systemic hemodynamic disorders that might arise from local or systemic insufficient availability of NO or its bio-active NO derivates, respectively.     

Distribution of neuropeptides in the primary olfactory center of the heliothine moth <Emphasis Type="Italic">Heliothis virescens</Emphasis>

Neuropeptides are a diverse widespread class of signaling substances in the nervous system. As a basis for the analysis of peptidergic neurotransmission in the insect olfactory system, we have studied the distribution of neuropeptides in the antennal lobe of the moth Heliothis virescens. Immunocytochemical experiments with antisera recognizing A-type allatostatins (AST-As), Manduca sexta allatotropin (Mas-AT), FMRFamide-related peptides (FaRPs), and tachykinin-related peptides (TKRPs) have shown that members of all four peptide families are present in local interneurons of the antennal lobe. Whereas antisera against AST-As, Mas-AT, and FaRPs give similar staining patterns characterized by dense meshworks of processes confined to the core of all antennal-lobe glomeruli, TKRPs are present only in neurons with blebby processes distributed throughout each glomerulus. In addition to local neurons, a pair of centrifugal neurons with cell bodies in the lateral subesophageal ganglion, arborizations in the antennal lobe, and projections in the inner antenno-cerebral tracts exhibits tachykinin immunostaining. Double-label immunofluorescence has detected the co-localization of AST-As, Mas-AT, and FaRPs in certain local interneurons, whereas TKRPs occurs in a distinct population. MALDI-TOF mass spectrometry has revealed nearly 50 mass peaks in the antennal lobe. Seven of these masses (four AST-As, two N-terminally extended FLRFamides, and Mas-AT) match known moth neuropeptides. The data thus show that local interneurons of the moth antennal lobe are highly differentiated with respect to their neuropeptide content. The antennal lobe therefore represents an ideal preparation for the future analysis of peptide signaling in insect brain.     

Hydrophobic drug delivery by self-assembling triblock copolymer-derived nanospheres

We describe the synthesis and characterization of a family of biocompatible ABA-triblock copolymers that comprised of hydrophilic A-blocks of poly(ethylene glycol) and hydrophobic B-blocks of oligomers of suberic acid and desaminotyrosyl-tyrosine esters. The triblock copolymers spontaneously self-assemble in aqueous solution into nanospheres, with hydrodynamic diameters between 40 and 70 nm, that do not dissociate under chromatographic and ultracentrifugation conditions. These nanospheres form strong complexes with hydrophobic molecules, including the fluorescent dye 5-dodecanoylaminofluorescein (DAF) and the antitumor drug, paclitaxel, but not with hydrophilic molecules such as fluorescein and Oregon Green. The nanosphere-paclitaxel complexes retain in vitro the high antiproliferative activity of paclitaxel, demonstrating that these nanospheres may be useful for delivery of the hydrophobic drugs.     

Diagnostic polymorphisms in the mitochondrial cytochrome b gene allow discrimination between cattle,sheep, goat,roe buck and deer by PCR-RFLP

Background  

As an alternative to direct DNA sequencing of PCR products, random PCR-RFLP is an efficient technique to discriminate between species. The PCR-RFLP-method is an inexpensive tool in forensic science, even if the template is degraded or contains only traces of DNA from various species.     

Impaired plasma fatty acid oxidation in extremely obese women

Skeletal muscle from extremely obese individuals exhibits decreased lipid oxidation compared with muscle from lean controls. It is unknown whether this effect is observed in vivo or whether the phenotype is preserved after massive weight loss. The objective of this study was to compare free fatty acid (FFA) oxidation during rest and exercise in female subjects who were either lean [n = 7; body mass index (BMI) = 22.6 +/- 2.2 kg/m(2)] or extremely obese (n = 10; BMI = 40.8 +/- 5.4 kg/m(2)) or postgastric bypass patients who had lost >45 kg (weight reduced) (n = 6; BMI = 33.7 +/- 9.9 kg/m(2)) with the use of tracer ([(13)C]palmitate and [(14)C]acetate) methodology and indirect calorimetry. The lean group oxidized significantly more plasma FFA, as measured by percent fatty acid uptake oxidized, than the extremely obese or weight-reduced group during rest (66.6 +/- 14.9 vs. 41.5 +/- 16.4 vs. 39.9 +/- 15.3%) and exercise (86.3 +/- 11.9 vs. 56.3 +/- 22.1 vs. 57.3 +/- 20.3%, respectively). BMI significantly correlated with percent uptake oxidized during both rest (r = -0.455) and exercise (r = -0.459). In conclusion, extremely obese women and weight-reduced women both possess inherent defects in plasma FFA oxidation, which may play a role in massive weight gain and associated comorbidities.     

Molecular cloning and functional characterization of the bovine (Bos taurus) organic anion transporting polypeptide Oatp1a2 (Slco1a2)

We describe the cloning, functional characterization and tissue localization of a novel membrane transporter of the OATP/Oatp-gene family obtained from liver and kidney of cattle (Bos taurus). The carrier protein exhibits highest sequence identity to the human OATP1A2 (previously called OATP-A) and is, therefore, named bovine Oatp1a2. Bovine Oatp1a2 received the gene symbol Slco1a2 that is identical to the SLC classification of human OATP1A2 (SLCO1A2, previously called SLC21A3) and is likely an orthologue of the human gene. Two different full-length bOatp1a2 cDNAs of 2316-bp and 3504-bp were obtained and encoded for a 666 amino acid membrane protein, which contains twelve putative transmembrane spanning domains. Bovine Oatp1a2 expression was detected in liver, kidney, brain and adrenal gland. Uptake studies in cRNA-injected oocytes demonstrated that bOatp1a2 transports estrone-3-sulfate and taurocholate, with K(m) values of 9.6 microM and 51 microM, respectively, and estradiol-17beta-glucuronide. However, the structurally-related heart glycosides ouabain (1 microM) and digoxin (1 microM) are neither transported by bovine Oatp1a2 nor by human OATP1A2. We conclude that based on the tested substrates bovine Oatp1a2 shows functional homology to human OATP1A2.     

Structural and biophysical characterization of the EphB4*ephrinB2 protein-protein interaction and receptor specificity

Increasing evidence implicates the interaction of the EphB4 receptor with its preferred ligand, ephrinB2, in pathological forms of angiogenesis and in tumorigenesis. To identify the molecular determinants of the unique specificity of EphB4 for ephrinB2, we determined the crystal structure of the ligand binding domain of EphB4 in complex with the extracellular domain of ephrinB2. This structural analysis suggested that one amino acid, Leu-95, plays a particularly important role in defining the structural features that confer the ligand selectivity of EphB4. Indeed, all other Eph receptors, which promiscuously bind many ephrins, have a conserved arginine at the position corresponding to Leu-95 of EphB4. We have also found that amino acid changes in the EphB4 ligand binding cavity, designed based on comparison with the crystal structure of the more promiscuous EphB2 receptor, yield EphB4 variants with altered binding affinity for ephrinB2 and an antagonistic peptide. Isothermal titration calorimetry experiments with an EphB4 Leu-95 to arginine mutant confirmed the importance of this amino acid in conferring high affinity binding to both ephrinB2 and the antagonistic peptide ligand. Isothermal titration calorimetry measurements also revealed an interesting thermodynamic discrepancy between ephrinB2 binding, which is an entropically driven process, and peptide binding, which is an enthalpically driven process. These results provide critical information on the EphB4*ephrinB2 protein interfaces and their mode of interaction, which will facilitate development of small molecule compounds inhibiting the EphB4*ephrinB2 interaction as novel cancer therapeutics.