Native arthropods on exotic sand dune flowers: consideration of sample size and number for investigating rare species and sparse communities

When studying arthropod visitors of flowers, the sampling unit (individual flowers, groups of flowers, areas of plants, timed visits, etc.) depends upon the aim of the study and the sampling method employed. In this study, arthropods using flowers of the ice plant, Carpobrotus edulis, were recorded on the sand dunes at New Brighton in the south island of New Zealand. Of 3600 flowers, only 10% contained invertebrates and only 478 specimens were recorded in total. Of 32 arthropod species observed on this exotic plant, we consider at least 20 to be native to New Zealand and five species are probably New Zealand endemics. Based on an occupation rate of individual flowers of 10%, a binomial model indicated that a sample of 100 flowers would have <0.003% chance of containing no specimens, and 96% chance that 5–16 flowers would contain some animals. Species accumulation models (e.g. bootstrap, Chao and rarefaction) and models examining the likelihood of recording rare species indicated that after examining 2000 flowers, 80% of arthropod species would be recorded, and that only the rarest species in our study would fall below an 80% statistical power of detection. The results suggest that for this flower–invertebrate system, a scheme that involved 20 independent samples, each consisting of 100 flowers, would provide a good chance of (1) avoiding totally empty samples (2) collecting a high proportion of the total species present and (3) recording all but the very rarest species that occur in this system.     

Hosts are more important than destinations: What genetic variation in Microctonus aethiopoides (Hymenoptera: Braconidae) means for foreign exploration for natural enemies

Nucleotide sequence data were generated from the gene regions COI, 16S, and arginine kinase to assess genetic variation within the Palearctic parasitoid, Microctonus aethiopoides, reared from Sitona discoideus, S. hispidulus, and Hypera postica collected from two proximate locations in Mediterranean France. Partitioned Bayesian phylogenetic analyses of the molecular data provided strong support for the presence of at least two M. aethiopoides biotypes, one associated with Hypera species and the other with Sitona species. These new results combined with previously published data from 14 countries show that M. aethiopoides genetic variation is much more strongly correlated with host taxon than with sampling location. This contrasts with earlier perceptions that M. aethiopoides exhibits significant geographic variation, and helps to explain the widely varying biological control outcomes that have been obtained following the introductions of M. aethiopoides to Australia, New Zealand, and North America. The results strongly suggest that success rates and environmental safety in biological control would both be improved by ensuring that parasitoids collected in the native range are reared from the same host species as the one being targeted for control in the region of introduction. The results also provided insights both on the evolution of M. aethiopoides' host range, and on its evolutionary transition between solitary and gregarious larval development.     

Algorithm of OMA for large-scale orthology inference

Background  

OMA is a project that aims to identify orthologs within publicly available, complete genomes. With 657 genomes analyzed to date, OMA is one of the largest projects of its kind.     

Microrheology of hyaluronan solutions: implications for the endothelial glycocalyx

The endothelial glycocalyx (EG) is a complex biopolymer network produced by vascular endothelial cells that forms a layer with multiple functions at the luminal side of blood vessels. The EG acts as an anti-adhesive protection layer, as a molecular sieve, as a chemical sensor site, and as a mechanotransducer of fluid shear stress to the underlying cell layer. A major component involved in these processes is the highly hydrated glycosaminoglycan (GAG) hyaluronan (HA). Here we used laser interferometry to measure the broadband mechanical response of reconstituted HA solutions at close to physiological conditions. HA showed rheological behavior consistent with that of a flexible polymer. The elastic behavior observed for entangled HA networks showed reptational relaxation with a large distribution of time scales, which disappeared quickly (15 min) with the addition of hyaluronidase (HAase). We conclude that the broadband mechanical probing of model systems (HA solutions) provides quantitative data that are crucial to understand the mechanical response of the EG in vivo and its role in mechanosensing.     

Combined molecular and morphological phylogenetic analyses of the New Zealand wolf spider genus Anoteropsis (Araneae: Lycosidae)

Datasets from the mitochondrial gene regions NADH dehydrogenase subunit I (ND1) and cytochrome c oxidase subunit I (COI) of the 20 species in the New Zealand wolf spider (Lycosidae) genus Anoteropsis were generated. Sequence data were phylogenetically analysed using parsimony and maximum likelihood analyses. The phylogenies generated from the ND1 and COI sequence data and a previously generated morphological dataset were significantly congruent (p<0.001). Sequence data were combined with morphological data and phylogenetically analysed using parsimony. The ND1 region sequenced included part of tRNA^Leu(CUN), which appears to have an unstable amino-acyl arm and no TψC arm in lycosids. Analyses supported the existence of five species groups within Anoteropsis and the monophyly of species represented by multiple samples. A radiation of Anoteropsis species within the last five million years is inferred from the ND1 and COI likelihood phylograms, habitat and geological data, which also indicates that Anoteropsis arrived in New Zealand some time after it separated from Gondwana.     

Partial recovery of the endothelial glycocalyx upon rosuvastatin therapy in patients with heterozygous familial hypercholesterolemia

The endothelial glycocalyx has been shown to serve as a protective barrier between the flowing blood and the vessel wall in experimental models. The aim of this study was to evaluate whether hypercholesterolemia is associated with glycocalyx perturbation in humans, and if so, whether statin treatment can restore this. We measured systemic glycocalyx volume (V(G)) in 13 patients with heterozygous familial hypercholesterolemia (FH) after cessation of lipid-lowering therapy for a minimum of 4 weeks and 8 weeks after initiating rosuvastatin therapy. Normocholesterolemic subjects were used as controls. V(G) was estimated by subtracting the intravascular distribution volume of a glycocalyx permeable tracer (dextran 40) from that of a glycocalyx impermeable tracer (labeled erythrocytes). V(G) in untreated FH patients [LDL 225 +/- 57 mg/dl (mean +/- SD)] was significantly reduced compared with controls (LDL 93 +/- 24 mg/dl) (V(G) 0.8 +/- 0.3 vs. 1.7 +/- 0.6, respectively, P < 0.001). After normalization of LDL levels (95 +/- 33 mg/dl) upon 8 weeks of statin treatment, V(G) recovered only partially (V(G) 1.1 +/- 0.4 L, P = 0.04). The endothelial glycocalyx is profoundly reduced in FH patients, which may contribute to increased atherogenic vulnerability. This perturbation is partially restored upon short-term statin therapy.     

Endothelial surface layer degradation by chronic hyaluronidase infusion induces proteinuria in apolipoprotein E-deficient mice

Objective

Functional studies show that disruption of endothelial surface layer (ESL) is accompanied by enhanced sensitivity of the vasculature towards atherogenic stimuli. However, relevance of ESL disruption as causal mechanism for vascular dysfunction remains to be demonstrated. We examined if loss of ESL through enzymatic degradation would affect vascular barrier properties in an atherogenic model.

Methods

Eight week old male apolipoprotein E deficient mice on Western-type diet for 10 weeks received continuous active or heat-inactivated hyaluronidase (10 U/hr, i.v.) through an osmotic minipump during 4 weeks. Blood chemistry and anatomic changes in both macrovasculature and kidneys were examined.

Results

Infusion with active hyaluronidase resulted in decreased ESL (0.32±0.22 mL) and plasma volume (1.03±0.18 mL) compared to inactivated hyaluronidase (0.52±0.29 mL and 1.28±0.08 mL, p<0.05 respectively).Active hyaluronidase increased proteinuria compared to inactive hyaluronidase (0.27±0.02 vs. 0.15±0.01 µg/µg protein/creatinin, p<0.05) without changes in glomerular morphology or development of tubulo-interstitial inflammation. Atherosclerotic lesions in the aortic branches showed increased matrix production (collagen, 32±5 vs. 18±3%; glycosaminoglycans, 11±5 vs. 0.1±0.01%, active vs. inactive hyaluronidase, p<0.05).

Conclusion

ESL degradation in apoE deficient mice contributes to reduced increased urinary protein excretion without significant changes in renal morphology. Second, the induction of compositional changes in atherogenic plaques by hyaluronidase point towards increased plaque vulnerability. These findings support further efforts to evaluate whether ESL restoration is a valuable target to prevent (micro) vascular disease progression.     

Structural and functional analysis of the GABARAP interaction motif (GIM)

Through the canonical LC3 interaction motif (LIR), [W/F/Y]‐X₁‐X₂‐[I/L/V], protein complexes are recruited to autophagosomes to perform their functions as either autophagy adaptors or receptors. How these adaptors/receptors selectively interact with either LC3 or GABARAP families remains unclear. Herein, we determine the range of selectivity of 30 known core LIR motifs towards individual LC3s and GABARAPs. From these, we define a I nteraction 相似文献