Plant phylogeny drives arboreal caterpillar assemblages across the Holarctic

1. Assemblages of insect herbivores are structured by plant traits such as nutrient content, secondary metabolites, physical traits, and phenology. Many of these traits are phylogenetically conserved, implying a decrease in trait similarity with increasing phylogenetic distance of the host plant taxa. Thus, a metric of phylogenetic distances and relationships can be considered a proxy for phylogenetically conserved plant traits and used to predict variation in herbivorous insect assemblages among co‐occurring plant species.
2. Using a Holarctic dataset of exposed‐feeding and shelter‐building caterpillars, we aimed at showing how phylogenetic relationships among host plants explain compositional changes and characteristics of herbivore assemblages.
3. Our plant–caterpillar network data derived from plot‐based samplings at three different continents included >28,000 individual caterpillar–plant interactions. We tested whether increasing phylogenetic distance of the host plants leads to a decrease in caterpillar assemblage overlap. We further investigated to what degree phylogenetic isolation of a host tree species within the local community explains abundance, density, richness, and mean specialization of its associated caterpillar assemblage.
4. The overlap of caterpillar assemblages decreased with increasing phylogenetic distance among the host tree species. Phylogenetic isolation of a host plant within the local plant community was correlated with lower richness and mean specialization of the associated caterpillar assemblages. Phylogenetic isolation had no effect on caterpillar abundance or density. The effects of plant phylogeny were consistent across exposed‐feeding and shelter‐building caterpillars.
5. Our study reveals that distance metrics obtained from host plant phylogeny are useful predictors to explain compositional turnover among hosts and host‐specific variations in richness and mean specialization of associated insect herbivore assemblages in temperate broadleaf forests. As phylogenetic information of plant communities is becoming increasingly available, further large‐scale studies are needed to investigate to what degree plant phylogeny structures herbivore assemblages in other biomes and ecosystems.

     

The spinal cord supports of vertebrae in the crown‐group salamanders (Caudata,Urodela)

The development of spinal cord supports (bony thickenings which extend into the vertebral canal of vertebrae) in primitive (Salamandrella keyserlingii) and derived (Lissotriton vulgaris) salamanders were described. The spinal cord supports develop as the protuberances of periostal bone of the neural arches in the anteroproximal part of the septal collagenous fibers which connect a transverse myoseptum with the notochord and spinal cord, in the septal bundle inside the vertebral canal. Spinal cord supports were also found in some teleostean (Salmo salar, Oncorhynchus mykiss) and dipnoan (Protopterus sp.) fishes. The absence of the spinal cord supports in vertebrates with cartilaginous vertebrae (lampreys, chondrichthyan, and chondrostean fishes) corresponds to the fact that the spinal cord supports are bone structures. The absence of the spinal cord supports in frogs correlates with the lack of the well developed septal bundles inside the vertebral canal. The spinal cord supports are, presumably, a synapomorphic character for salamanders which originated independently of those observed in teleostean and dipnoan fishes. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.     

A determination key to the structural types of seattered green using the air multispectral photography

Scattered green was studied in Czechoslovakia by means of the air multispectral photography and of the field observation. According to various repartition and canopy 19 structural types of seattered green were derived.     

Peptides and multiple antigen peptides from Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase: preparation, immunogenicity and immunoprotective capacity in C57BL/6 mice.

Four monoepitopic MAPs (MAP A, B, C and E) and one bis-diepitopic MAP B-E derived fromthe primary sequence of Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase, previously tested in BALB/c mice, were examined for their immunogenicity and protective capacity in C57BL/6 mice. Despite multimerization into MAPs, MAP Aand MAP C were poorly immunogenic. In contrast toBALB/c mice, MAP E was non-immunogenic in C57BL/6 mice. Peptide B in the form of MAP B orbis-diepitopic MAPB-E elicited immune responses in C57BL/6 mice that were associated with a significant decrease in worm burden. The MAPs were prepared by the stepwise solid-phase peptide synthesis using Boc/Bzl chemistry, successfully purified on the RP-HPLC column and characterized by RP-HPLC, HPCE and MALDI-TOF MS techniques. A general strategy for MAPs purification is discussed here and the purification of MAP Band MAP E is documented in detail.     

Properties of the superoxide-generating oxidase of B-lymphocyte cell lines. Determination of Michaelis parameters.

The capacity of three B-lymphocyte cell lines to generate superoxide (O2.-) was examined. The Burkitt lymphoma lines P.3HR-1 and Jijoye gave no response to phorbol 12-myristate 13-acetate (PMA) at 100 ng/ml but produced up to 0.35 nmol of O2.-/min per mg of protein when stimulated with 5 micrograms of PMA/ml; the cell line RPMI 1788 produced Nitro Blue Tetrazolium-positive responses to low PMA concentrations and approx. 0.4 nmol of O2.-/min per mg of protein at 5 micrograms of PMA/ml. Each cell line contained approx. 10 pmol of low-potential cytochrome b (cytochrome b-245)/mg of protein. Homogenates of PMA-activated cells gave 10-20-fold greater rates of O2.- produced per mg of protein. The Km for NADPH varied between approx. 250 microM for P3.HR-1 and RPMI 1788 cell lines and 30.5 +/- 6.5 microM for the Jijoye cell line; the Km values for NADH were higher. Determination of intracellular NADPH concentration showed that this might limit the rate of O2.- production since in each cell line it was at or below the Km concentration.     

Mannose 6-phosphate/insulin-like growth factor II-binding proteins in human serum and urine. Their relation to the mannose 6-phosphate/insulin-like growth factor II receptor.

Human serum and urine contain polypeptides which bind mannose 6-phosphate (M6P) and insulin-like growth factor II (IGF II) and crossreact with antibodies against the M6P/IGF II receptor. These polypeptides are considered to be fragments of the M6P/IGF II receptor. The major Mr approx. 205,000 fragment in serum and urine is about 10 kDa smaller in size than the membrane-associated receptor and is accompanied by minor forms with Mr values ranging from 104,000 to 180,000. The presence of receptor fragments in biological fluids indicates that shedding is one of the mechanisms contributing to the turnover of the M6P/IGF II receptor and that receptor fragments are part of the heterogenous group of serum proteins whic bind IGF II.     

The superoxide generating system of B cell lines. Structural homology with the phagocytic oxidase and triggering via surface Ig

EBV-transformed B lymphocyte cell lines (EBV-BLCL) produce superoxide after stimulation with phorbol ester, a capacity unique among nonmyeloid cells. The superoxide producing system of EBV-BLCL (B cell oxidase) was compared with the phagocytic NADPH-oxidase and the relationship of the capacity to produce superoxide to the presence of the EBV-genome was analyzed. The two EBV-transformed B cell lines F1 and HELL generated superoxide in response to PMA (2.3 nmol/10(6) F1 cells x 1 h and 6.27 nmol/10(6) HELL cells x 1 h with 1 microgram/ml of PMA), whereas no superoxide release was detected with the EBV-positive Burkitt lymphoma line WIL-2 and the EBV-negative plasmocytoma line U-266. Also, F1 and HELL showed lucigenin-dependent chemiluminescence (CL) after PMA-treatment, whereas no CL responses were detected from WIL-2 or U-266. Further, F1 and HELL cells contained a low potential cytochrome b-245 (10.9 and 61.0 pmol/mg protein, respectively) and also a 45 kDa diphenylene-iodonium (DPI)-binding peptide, both components of the phagocytic NADPH-oxidase. In contrast, neither the cytochrome b-245 nor the 45 kDa DPI-binding peptide were detected in WIL-2 and U-266. In addition, DPI inhibited O2- production by PMA-stimulated EBV-BLCL and polymorphonuclear granulocytes. Further, F1 line cells showed superoxide dismutase-inhibitable lucigenin-dependent CL when triggered by protein A-bearing staphylococci (Cowan strain I) or by a mAb directed against human IgG in the presence of solid-phase goat anti-mouse-Ig antibody. From a panel of eight EBV-BLCL, only five responded with CL when exposed to protein A-bearing staphylococci, whereas all showed CL when treated with phorbol ester. Inasmuch as all eight EBV-BLCL possessed surface Ig and a "functional" oxidase, their differential response to cross-linking of surface Ig may be determined by differences in signal transduction. Superoxide production by EBV-BLCL appears thus related to expression of an electron transport chain structurally homologous, if not identical, with the "phagocytic" NADPH-oxidase. Apparently, the presence of EBV-genome in B cell lines does not per se lead to expression of this oxidase. This suggests that nontransformed B cells may, at a certain differentiation stage, also express a superoxide-generating chain. From the finding of stimulation of superoxide production of EBV-BLCL via surface Ig it appears possible that also Ag may be able to trigger such B cells to production of superoxide which might have an important role in the physiology of B cells.     

A single-photon imaging system for the simultaneous quantitation of luminescent emissions from multiple samples

A combination of a two-dimensional photon detector (double-microchannel plate) with single-photon sensitivity and an optical projection system that allows space-resolved quantitation of luminescent emissions from spatially extended objects is described. A "luminescent image" of the object focused onto the detector is accumulated over a preset time and stored in a digital frame memory from which photon counts over areas of interest can be read. In this study, the object consisted of a microtiter plate containing luminescent samples which was placed below a projecting lens (2.0/21 mm, 36 X 24-mm format camera lens) at a distance of 38.5 cm. Although geometry substantially limited photon collection, the sensitivity achieved was only 10X less than that obtained with a dedicated photon-counting luminometer. A slightly diminished photon collection from peripheral wells was apparently caused by the projection system and could be corrected arithmetically. Both chemically generated luminescence (ATP bioluminescence) and cell-derived, superoxide-dependent luminescence (with lucigenin as chemilumigenic probe) were detected with excellent spatial resolution and linearity of response over a wide range.     

Enhancement of chloroplast energization in Chlorella by treatments inactivating the nitrate-reducing system

Inactivation of the nitrate-reducing system in whole cells of Chlorella vulgaris Bejerinck by darkening, nitrogen starvation, ammonium, or cycloheximide brings cells into a state with a high yield of the millisecond-delayed fluorescence of chlorophyll. Activation of this system by illumination, by adding glucose to dark-adapted cells or nitrate to nitrogen-starved cells brings the cells into a low-yield state. The transitions between the lowand high-yield state induced by alternating light and dark periods are suppressed by tungstate and restored by subsequent molybdate addition. The drop in the delayed-fluorescence yield upon activation of the nitrate-reducing system is associated with the decrease of the amplitude of the electrochemical proton gradient across the thylakoid membrane of the chloroplast, as evidenced by the kinetics of the light-induced adsorption changes at 520 nm. The decrease of the proton gradient may be caused by the electron flow diverting from the cyclic path in photosystem I as a result of the activation of the electron transfer from ferredoxin to nitrite.Abbreviation DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea