Lethal effects and ultrastructure of cellular uptake of ingested gold nanoparticles in the freshwater rotifer Brachionus calyciflorus (Monogononta: Brachionidae).

Much of the recent literature concerning the threat posed by anthropogenic microscopic pollution has focussed on marine organisms although freshwater environments face the same degree of pollution and therefore risk. Although several studies have documented the ingestion of nanoparticles (NPs) in species of the pelagic freshwater rotifer genus Brachionus, unambiguous evidence for its cellular uptake in this group remains lacking. We therefore used transmission electron microscopy (TEM) of ultrathin sections through the digestive tract of individuals of Brachionus calyciflorus exposed in vitro to citrate stabilized gold nanoparticles (AuCit NPs) in their culture medium to provide the first concrete evidence for the cellular uptake of NPs in rotifers, a group of organisms that comprise an important part of the zooplankton community.

18S rRNA variability maps reveal three highly divergent, conserved motifs within Rotifera.

Background: 18S rRNA is a major component of the small subunit of the eukaryotic ribosome and an important phylogenetic marker for many groups, often to the point of being the only marker available for some. A core structure across eukaryotes exists for this molecule that can help to inform about its evolution in different groups. Using an alignment of 18S rDNA for Rotifera as traditionally recognized (=Bdelloidea, Monogononta, and Seisonacea, but not Acanthocephala), I fitted sequences for three exemplar species (Adineta vaga, Brachionus plicatilis, and Seison nebaliae, respectively) to the core structure and used these maps to reveal patterns of evolution for the remainder of this diverse group of microscopic animals.

A weighted taxonomic matrix key for species of the rotifer genus (Rotifera, Monogononta, Synchaetidae).

A new, weighted matrix identification key for 34 largely undisputed species of was created with the aim of providing comparable, detailed and diagnostic character sets for each species that can be applied to live and/or preserved specimens. As part of this process, 14 species of were intensively re-investigated with respect to their habitus and trophi morphology using binocular, light, and scanning electron microscopy, which, together with behavioural observations, revealed several new discriminating characters. Whenever possible, missing information for any character was added for the remaining species from the literature, with the two recently described species and being considered for the first time in an identification key.

Cloning of a novel trypsin inhibitor from the Traditional Chinese medicine decoction pieces, Radix Trichosanthis.

Most herbs of traditional Chinese medicine (TCM) are used as air-dried decoction pieces that are manufactured and kept at ambient temperature for long periods. Given the ability of some desiccation-tolerant plants to conserve RNA, it could be worthwhile to isolate mRNA from TCM decoction pieces as part of a transcriptomic strategy to identify new substances with potential pharmaceutical application. Here, we report the molecular cloning of a novel trypsin inhibitor (as the probable alleleic variants TKTI-2 and TKTI-3) from the decoction piece of Radix Trichosanthis, representing the dried root of Trichosanthes kirilowii.

Evaluation of the bioactivity of a mastoparan peptide from wasp venom and of its analogues designed through targeted engineering.

Mastoparan is a typical cationic and amphipathic tetradecapeptide found in wasp venom and exhibits potent biological activities. Yet, compared with other insect-derived peptides, such as melittin from the bee venom, this family have been underrated. Herein, we evaluated the biological activities of mastoparan-C (MP-C), which was identified from the venom of the European Hornet (), and rationally designed two analogues (a skeleton-based cyclization by two cysteine residues and an N-terminal extension via tat-linked) for enhancing the stability of the biological activity and membrane permeability, respectively.

Discovery of Distinctin-Like-Peptide-PH (DLP-PH) From the Skin Secretion of , a Prototype of a Novel Family of Antimicrobial Peptide.

Amphibian skin secretions are an important treasure house of bioactive antimicrobial peptides (AMPs). Despite having been the focus of decades of research in this context, investigations of phyllomedusine frogs continue to identify new AMPs from their skin secretions. In this study, the prototype of a novel family of AMP distinctin-like-peptide-PH (DLP-PH) was identified from the skin secretion of the otherwise well-studied Tiger-Legged Tree Frog through cloning of its precursor-encoding cDNA from a skin secretion-derived cDNA library by a 3'-rapid amplification of cDNA ends (RACE) strategy.

Targeted Modification of a Novel Amphibian Antimicrobial Peptide from to Enhance Its Activity against MRSA and Microbial Biofilm.

Antimicrobial peptides (AMPs) in the skin secretions of amphibians are fundamental components of a unique defense system that has evolved to protect these hosts from microbial invasion. Medusins constitute a recently-discovered AMP family from phyllomedusine leaf frog skin and exhibit highly-conserved structural characteristics. Here, we report a novel medusin, medusin-PT, from the skin secretion of the Tarsier Leaf Frog, .

Does retinal configuration make the head and eyes of foveate birds move?

Animals move their heads and eyes to compensate for movements of the body and background, search, fixate, and track objects visually. Avian saccadic head/eye movements have been shown to vary considerably between species. We tested the hypothesis that the configuration of the retina (i.

Evidence Supporting the Uptake and Genomic Incorporation of Environmental DNA in the "Ancient Asexual" Bdelloid Rotifer Philodina roseola.

Increasing evidence suggests that bdelloid rotifers regularly undergo horizontal gene transfer, apparently as a surrogate mechanism of genetic exchange in the absence of true sexual reproduction, in part because of their ability to withstand desiccation. We provide empirical support for this latter hypothesis using the bdelloid Philodina roseola, which we demonstrate to readily internalize environmental DNA in contrast to a representative monogonont rotifer (Brachionus rubens), which, like other monogononts, is facultative sexual and cannot withstand desiccation. In addition, environmental DNA that was more similar to the host DNA was retained more often and for a longer period of time.

The diversity and evolution of anuran skin peptides.

Amphibians exhibit various, characteristic adaptations related to their "incomplete" shift from the aquatic to the terrestrial habitat. In particular, the integument was subject to a number of specialized modifications during the evolution of these animals. In this review, we place special emphasis on endogenous host-defence skin peptides from the cuteanous granular glands anuran amphibians (frogs and toads).

Phylogenetically related and ecologically similar carnivores harbour similar parasite assemblages.

Most parasites infect multiple hosts, but what factors determine the range of hosts a given parasite can infect? Understanding the broad scale determinants of parasite distributions across host lineages is important for predicting pathogen emergence in new hosts and for estimating pathogen diversity in understudied host species. In this study, we used a new data set on 793 parasite species reported from free-ranging populations of 64 carnivore species to examine the factors that influence parasite sharing between host species. Our results showed that parasites are more commonly shared between phylogenetically related host species pairs.

Evolution of the cation chloride cotransporter family: ancient origins, gene losses, and subfunctionalization through duplication.

The cation chloride cotransporter (CCCs) family comprises of four subfamilies-K(+)-Cl(-) cotransporters (KCCs), Na(+)-K(+)-2Cl(-) cotransporters (NKCCs), and Na(+)-Cl(-) cotransporters (NCCs)-and possibly two additional members-CCC interacting protein (CIP1) and polyamine transporters (CCC9)-as well. Altogether, CCCs can play essential physiological roles in transepithelial ion reabsorption and secretion, cell volume regulation, and inhibitory neurotransmission and so are present across all domains of life. To gain insight into the evolution of this family, we performed a comprehensive phylogenetic analysis using publically available genomic information.

Time-dependent gene expression analysis of the developing superior olivary complex.

The superior olivary complex (SOC) is an essential auditory brainstem relay involved in sound localization. To identify the genetic program underlying its maturation, we profiled the rat SOC transcriptome at postnatal days 0, 4, 16, and 25 (P0, P4, P16, and P25, respectively), using genome-wide microarrays (41,012 oligonucleotides (oligos)). Differences in gene expression between two consecutive stages were highest between P4 and P16 (3.

Amalgamating source trees with different taxonomic levels.

Supertree methods combine a collection of source trees into a single parent tree or supertree. For almost all such methods, the terminal taxa across the source trees have to be non-nested for the output supertree to make sense. Motivated by Page, the first supertree method for combining rooted source trees where the taxa can be hierarchically nested is called AncestralBuild.

A novel method for comparative analysis of retinal specialization traits from topographic maps.

Vertebrates possess different types of retinal specializations that vary in number, size, shape, and position in the retina. This diversity in retinal configuration has been revealed through topographic maps, which show variations in neuron density across the retina. Although topographic maps of about 300 vertebrates are available, there is no method for characterizing retinal traits quantitatively.

Molecular cloning of skin peptide precursor-encoding cDNAs from tibial gland secretion of the Giant Monkey Frog, Phyllomedusa bicolor (Hylidae, Anura).

The skins of phyllomedusine frogs have long been considered as being tremendously rich sources of bioactive peptides. Previous studies of both peptides and cloning of their precursor encoding cDNAs have relied upon methanolic skin extracts or the dissected skins of recently deceased specimens and have not considered the different glands in isolation. We therefore focused our attention on the tibial gland of the Giant Monkey Frog, Phyllomedusa bicolor and constructed a cDNA library from the skin secretion that was obtained via mechanical stimulation of this macrogland.

Antimicrobial peptides and alytesin are co-secreted from the venom of the Midwife toad, Alytes maurus (Alytidae, Anura): implications for the evolution of frog skin defensive secretions.

The skin secretions of frogs and toads (Anura) have long been a known source of a vast abundance of bioactive substances. In the past decade, transcriptome data of the granular glands of anuran skin has given new impetus to investigations of the putative constituent peptides. Alytes obstetricans was recently investigated and novel peptides with antimicrobial activity were isolated and functionally characterised.

Comment on "Impacts of the Cretaceous Terrestrial Revolution and KPg extinction on mammal diversification".

Meredith et al. (Reports, 28 October 2011, p. 521) question three findings of our delayed-rise hypothesis for present-day mammals made with reference to the Cretaceous-Paleogene (KPg) boundary, based on their new time tree of the group.

Are voluntary wheel running and open-field behavior correlated in mice? Different answers from comparative and artificial selection approaches.

Voluntary wheel running and open-field behavior are probably the two most widely used measures of locomotion in laboratory rodents. We tested whether these two behaviors are correlated in mice using two approaches: the phylogenetic comparative method using inbred strains of mice and an ongoing artificial selection experiment on voluntary wheel running. After taking into account the measurement error and phylogenetic relationships among inbred strains, we obtained a significant positive correlation between distance run on wheels and distance moved in the open-field for both sexes.

Updating the evolutionary history of Carnivora (Mammalia): a new species-level supertree complete with divergence time estimates.

Background: Although it has proven to be an important foundation for investigations of carnivoran ecology, biology and evolution, the complete species-level supertree for Carnivora of Bininda-Emonds et al. is showing its age. Additional, largely molecular sequence data are now available for many species and the advancement of computer technology means that many of the limitations of the original analysis can now be avoided.

Inferring the Tree of Life: chopping a phylogenomic problem down to size?

The combination of molecular sequence data and bioinformatics has revolutionized phylogenetic inference over the past decade, vastly increasing the scope of the evolutionary trees that we are able to infer. A recent paper in BMC Biology describing a new phylogenomic pipeline to help automate the inference of evolutionary trees from public sequence databases provides another important tool in our efforts to derive the Tree of Life.

Complete, accurate, mammalian phylogenies aid conservation planning, but not much.

In the face of unprecedented global biodiversity loss, conservation planning must balance between refining and deepening knowledge versus acting on current information to preserve species and communities. Phylogenetic diversity (PD), a biodiversity measure that takes into account the evolutionary relationships between species, is arguably a more meaningful measure of biodiversity than species diversity, but cannot yet be applied to conservation planning for the majority of taxa for which phylogenetic trees have not yet been developed. Here, we investigate how the quality of data on the taxonomy and/or phylogeny of species affects the results of spatial conservation planning in terms of the representation of overall mammalian PD.

The genome of Oryctes rhinoceros nudivirus provides novel insight into the evolution of nuclear arthropod-specific large circular double-stranded DNA viruses.

The Oryctes rhinoceros nudivirus (OrNV) is a dsDNA virus with enveloped, rod-shaped virions. Its genome is 127,615 bp in size and contains 139 predicted protein-coding open reading frames (ORFs). In-depth genome sequence comparisons revealed a varying number of shared gene homologues, not only with other nudiviruses (NVs) and baculoviruses, but also with other arthropod-specific large dsDNA viruses, including the so-called Monodon baculovirus (MBV), the salivary gland hypertrophy viruses (SGHVs) and white spot syndrome virus (WSSV).