Colonization of a host tree by herbivorous insects under a changing climate

Climate warming has been predicted to increase the abundance of herbivorous insects. Together with concurrent poleward shifts in many insect species this may increase herbivore pressure on plants. However, the manner in which plants at higher latitudes become colonized by herbivorous insects in the future is unknown. We established a translocation experiment using 26 micropropagated silver birch Betula pendula genotypes from six populations originating from 60°N to 67°N, to study the susceptibility of the translocated birches to local herbivores. The birches were planted at three different latitudes in Finland (60°N, 62°N and 67°N). We studied the effect of source population and latitudinal translocation on herbivore density, species richness, and community composition among the genotypes growing in the same environmental conditions in two years; 2011 and 2012. The source population explained the variation in the herbivore density only in 2012, whereas latitudinal translocation did not affect herbivore density. Variation in species richness was not explained by the source population or by the latitudinal translocation. At two of the study sites, the similarity of the herbivore communities among the populations decreased with increasing latitudinal distance of the source populations, possibly because birch populations that grow geographically closer to each other are genetically more similar, and therefore support a more similar composition of the arthropod community. All birch genotypes were colonized by local herbivores, suggesting that as herbivores shift their ranges polewards, they are able to colonize novel host‐plant genotypes. This enables compositional changes in insect communities on their host plants in the future, which in turn, might affect total herbivory and eventually, plant growth.     

Heavy metal (Pb) accumulation in metallophytes as influenced by the variations in rhizospheric and non-rhizospheric soils physico-chemical characteristics

Activities at root-soil interface determine the solubility and uptake of metals by plants. Metal accumulation in plant species (Imperata cylindrical, Cynodon dactylon, Eleucine indica, Gomphrena celosoides, Sporobolus pyramidalis, Chromolaena odorata and Rhynchospora corymbosa) growing on Pb contaminated site as influenced by variations in physico-chemical characteristics, dissolved organic matter (DOM), Pb fractionation and different functional groups (using Fourier Transmittance Infra-red) of rhizospheric and non-rhizospheric soils was assessed. The electrical conductivity (2660–5520 µs) and Pb concentrations (51390.0–64080.0 mg/kg) were more in non-rhizospheric than rhizospheric soils having 276 µs to 3160 µs EC and 3289.0 to 44850.0 mg/kg Pb. More nutrients, DOM and carbohydrates functional groups (C-O; 1100 -1000 and O-H; 3700–3600) were found in rhizospheric compared to non-rhizospheric soils. The pH was slightly acidic (5.0–5.54) and E. indica with the lowest pH (5.0) accumulated highest Pb concentrations in shoot (8030 mg/kg) and root (16380 mg/kg) while C. odorata with highest values of pH, P, Ca and Mg in rhizospheric soil accumulated the least (root; 331.6 and shoot: 209.0 mg/kg). Pb was more in organic and residual fractions of rhizospheric and non-rhizospheric soils respectively. Reduction in pH, EC coupled with nutrients and DOM availability increased Pb uptake by plants.     

Halomonas glaciei sp. nov. isolated from fast ice of Adelie Land,Antarctica

Eleven psychrophilic bacteria were isolated from a solid layer of fast ice in the middle of Pointe-Geologie Archipelago, Adelie Land, Antarctica. The 11 isolates based on the phenotypic characteristics, chemotaxonomic and phylogenetic analysis have been identified as members of the genus Halomonas. All the isolates at the 16S rDNA sequence level were identical, possessed the 15 conserved nucleotides of the family Halomonadaceae and four nucleotides of the genus Halomonas. Therefore, the 16S rDNA sequence of DD 39 was used for calculating the evolutionary distances and for phylogenetic analysis. It was observed that DD 39 formed a robust cluster with H. variabilis, from which it differed by 0.7%. Further DNA-DNA hybridization studies indicated low DNA-DNA homology (15%) between H. variabilis and DD 39. Between the 11 Antarctic isolates the homology was >85%. In addition it was observed that DD 39 was different from H. variabilis in that it was psychrophilic, could tolerate only up to 15% sodium chloride, could not hydrolyse esculin, could not reduce nitrate, was urease negative, could not utilize glycerol as a carbon source, and was resistant to ampicillin and erythromycin and sensitive to nalidixic acid. In addition, it also exhibited distinct differences with respect to high content of C(16:1) and low levels of cyclo-C(17:0) and cyclo-C(19:0). DD 39 also differed from all the other reported species of Halomonas with respect to many phenotypic characteristics. It is proposed therefore that DD 39 should be placed in the genus Halomonas as a new species that is Halomonas glaciei. The type strain of H. glaciei is DD 39(T) (MTCC 4321; JCM 11692).     

ARH is a modular adaptor protein that interacts with the LDL receptor,clathrin, and AP-2

Mutations in the phosphotyrosine binding domain protein ARH cause autosomal recessive hypercholesterolemia, a disorder caused by defective internalization of low density lipoprotein receptors (LDLR) in the liver. To examine the function of ARH, we used pull-down experiments to test for interactions between ARH, the LDLR, and proteins involved in clathrin-mediated endocytosis. The phosphotyrosine binding domain of ARH interacted with the internalization sequence (NPVY) in the cytoplasmic tail of LDLR in a sequence-specific manner. Mutations in the NPVY sequence that were previously shown to decrease LDLR internalization abolished in vitro binding to ARH. Recombinant ARH bound purified bovine clathrin with high affinity (K(D), approximately 44 nm). The interaction between ARH and clathrin was mapped to a canonical clathrin box sequence (LLDLE) in ARH and to the N-terminal domain of the clathrin heavy chain. A highly conserved 20-amino acid sequence in the C-terminal region of ARH bound the beta(2)-adaptin subunit of AP-2. Mutation of a glutamic acid residue in the appendage domain of beta(2)-adaptin that is required for interaction with the adapter protein beta-arrestin markedly reduced binding to ARH. These data are consistent with the hypothesis that ARH functions as an adaptor protein that couples LDLR to the endocytic machinery.     

Identification of a Human Cancer Related Organ-Specific Neoantigen

Human cancers express organ-specific neoantigens (OSNs) which elicit specific cellular immune responses in the cancer patient, as demonstrated by leukocyte adherence inhibition (LAI), an in vitro immune response assay. A purified protein of MW 40,000 (p40) exhibiting OSN (colon specific) activity was cleaved into specific peptide fragments and their partial amino acid sequences determined. This information was used in the polymerase chain reaction (PCR) to obtain a 992 bp cDNA clone (PCR-992) from a human colon adenocarcinoma cell line (LS-180). By comparison of the predicted amino acid sequence of PCR-992 with the known sequence of p40 peptides, PCR-992 was shown to correspond to almost the entire coding region of p40. Nucleotide sequence analysis suggested that the protein was mycoplasmal in origin due to its high A+T content (76%) and the presence of five in frame TGA termination codons; at least two of the latter are actually read as tryptophan, a known feature of mycoplasma translation. We have confirmed this origin by direct isolation of a contaminating mycoplasma species from the LS-180 cell line and demonstration that it could be hybridized with the PCR-992 probe. Northern and PCR analysis of RNA preparations from the contaminated LS-180 cell line showed that p40 was part of the high affinity transport system operon of Mycoplasma hyorhinis (Dudler et al, EMBO J., 7: 3963-3970, 1988). Total protein lysates of Mycoplasma hyorhinis cultivated without animal cells could elicit positive LAI responses when incubated with cancer patient leukocytes but not with normal patient leukocytes. The organ-specific nature of the response was, however, not observed indicating that host cell-mycoplasmal interactions may play a role in determining the organ-specific nature of p40 seen with the LAI. The significance of these findings will be discussed in the context of previous thinking regarding the origin of OSNs.     

Molecular docking analysis of penta galloyl glucose with the bcl-2 family of anti-apoptotic targets

Apoptosis requires cellular proteins from the B-cell lymphoma 2 (BCL-2) family linked to breast cancer. Therefore, it is of interest to document the Molecular docking analysis data of penta galloyl glucose with the bcl-2 family of anti-apoptotic targets (Bcl-2, BCL-XL, Caspase 3, and Caspase 9). Data shows that Pentagalloyl glucose have optimal binding features with Bcl-2, BCL-XL, Caspase 3, and Caspase 9 proteins with binding energy of -8.6,-7,-7.5 and 4.4 kcal/mol respectively for further consideration in this context.     

Indigenous Plants Demonstrating Effective Antioxidant Properties

Biology Bulletin - Increased production of antioxidant herbal supplements utilizing traditional medicinal plants has been attributed to a high margin of economic effectiveness, environmental...     

The synthesis and structure-activity relationships of 3-amino-4-benzylquinolin-2-ones; discovery of novel KCNQ2 channel openers

3-amino-4-benzylquinolin-2-ones have been identified as a novel class of KCNQ2 channel openers. Synthesis and SAR is described along with their electrophysiological evaluation as activators of the cloned mKCNQ2 channel expressed in Xenopus laevis oocytes. The preliminary SAR data suggest the importance of both the trifluoromethylsulfonamido group and electron-withdrawing substituents on the quinolone nucleus for expression of KCNQ2 channel opening properties.     

Pruning of motor neuron branches establishes the DLM innervation pattern in Drosophila

During the Drosophila life-cycle two sets of neuromuscular junctions are generated: the embryonic/larval NMJs develop during the first half, followed by the period of metamorphosis during which the adult counterpart is generated. Development of the adult innervation pattern is preceded by a withdrawal of larval NMJs, which occurs at the onset of metamorphosis, and is followed by adult-specific motor neuron outgrowth to innervate the newly developing adult fibers. Establishment of the adult innervation pattern occurs in the context of a broader restructuring of the nervous system, which results in the development of neural circuits that are necessary to carry out behaviors specific to the adult. In this article, we follow development of the dorsal longitudinal muscle (DLM) innervation pattern through metamorphosis. We find that the initial period of motor neuron elaboration is followed by a phase of extensive pruning resulting in a threefold reduction of neuromuscular contacts. This event establishes the adult pattern of second order branching. Subsequent higher order branching from the second order "contact" points generates the characteristic multiterminal innervation pattern of the DLMs. Boutons begin to appear after the pruning phase, and are much smaller than their larval counterparts. Additionally, we demonstrate that the DLM innervation is altered in the hyperexcitable double mutant, ether a go-go Shaker, and that the phenotype is suppressed by the hypoexcitable mutant, nap(ts1). Our results demonstrate that electrical activity regulates the patterning of DLM innervation during metamorphosis.     

Transcriptional regulation of cyclooxygenase-2 in the Human Microvascular Endothelial Cell Line,HMEC-1: Control by the combinatorial actions of AP2, NF-IL-6 and CRE elements

Interleukin-1beta (IL-1) is a potent inducer of cyclooxygenase-2 (COX-2) and prostaglandin biosynthesis in many types of cells, yet little is known about the molecular mechanisms regulating IL-1 mediated prostanoid biosynthesis in the endothelium of the microvasculature. Therefore, we examined the cis- and trans-acting factors regulating IL-1-induced COX-2 expression in the human microvascular endothelial cell line, HMEC-1. IL-1 enhanced steady state levels of COX-2 protein and mRNA synthesis by approximately 2-fold which preceded a 2-fold increase in PGF(alpha) biosynthesis. Expression of a series of COX-2 promoter-luciferase constructs in IL-1 treated HMEC-1 cells revealed that the 'full length' (-1432/+59 bp) promoter was 10 times more active than the SV-40 promoter/enhancer and that it could be further activated by IL-1. Surprisingly however, all except for the shortest COX-2 promoter construct retained the ability to respond to IL-1 and luciferase activity driven by -191/+59 bp COX-2 promoter was as responsive to IL-1 as the full-length promoter. Moreover, site-directed promoter mutagenesis and electophoretic mobility shift assays (EMSA) indicate that the combinatorial actions of AP2, NF-IL6, and CRE elements are critical for both constitutive and IL-1-inducible COX-2 promoter activity. Understanding the mechanism(s) regulating COX-2 gene expression and prostaglandin biosynthesis in the microvasculature has important implications with regard to inflammation and angiogenesis in vivo.