Phylogeny of the hyper‐diverse rove beetle subtribe Philonthina with implications for classification of the tribe Staphylinini (Coleoptera: Staphylinidae)

With 71 genera and over 2700 described species, Philonthina is the most speciose subtribe of rove beetle tribe Staphylinini and forms a major component of the largest remaining higher systematics challenge in Staphylinini, the ‘Staphylinini propria’ clade. A related systematics issue concerns the position of the genus Holisus (Hyptiomina), which was recovered within the Neotropical philonthine lineage in several recent analyses of morphology. With the aims of resolving the phylogeny of Philonthina and the position and, thus, validity of Hyptiomina, we performed phylogenetic analyses of the tribe Staphylinini based on molecular (six genes, 4471 bp) and morphological (113 characters) data including 138 taxa from all relevant lineages of Staphylinini. We found that ‘Staphylinini propria’ is a monophylum consisting of six lineages: current subtribes Anisolinina, Philonthina, Staphylinina and Xanthopygina; and two new subtribes, Algonina Schillhammer and Brunke and Philothalpina Chatzimanolis and Brunke. While the previously hypothesized Neotropical lineage of Philonthina was corroborated, Holisus was recovered as a separate subtribe, outside of Philonthina, within an informal ‘Southern Hemisphere clade’. Based on our analyses, we propose tentative new concepts of the polyphyletic genera Belonuchus and Philonthus. We propose the following taxonomic changes: synonymy of the subtribes Staphylinina Latreille (valid name) and Eucibdelina Sharp; resurrection of genera Barypalpus Cameron and Trapeziderus Motschulsky from synonymy with Rientis Sharp and Belonuchus Nordmann, respectively; transfer of 38 Belonuchus species, 16 Hesperus Fauvel species and one Philonthus Stephens species to Trapeziderus as new combinations; transfer of two Hesperus species to Eccoptolonthus Bernhauer as new combinations; transfer of one Belonuchus species to Paederomimus Sharp as a new combination; and transfer of Pridonius Blackwelder new status from its position as a subgenus of Quedius (subtribe Quediina) to Philonthina as a genus, and new combinations for its two described species.     

The macroecology of reef fish agonistic behaviour

Understanding the interplay between processes operating at large and small spatiotemporal scales in shaping biotic interactions remains challenging. Recent studies illustrate how phenotypic specialization, species life-history traits and/or resource partitioning recurrently underlie the structure of mutualistic interactions in terrestrial ecosystems along large latitudinal gradients of biodiversity. However, we know considerably less about how local processes interact with large-scale patterns of biodiversity in modulating biotic interactions in the marine realm. Considering agonistic behaviour as a proxy for contest competition, we empirically investigate whether the structure of reef fish agonistic interactions is conserved across a 34 000-km longitudinal gradient of biodiversity. By sampling coral reefs using standardized remote underwater video, we found recurrent patterns of fish agonistic behaviour in disparate communities distributed across five biogeographic provinces of the Pacific and Atlantic oceans. While the sheer number of species increases with regional richness, the number of aggressive disputes at the habitat scale is similar across communities. We then combined generalized linear models and network theory to reveal that, the emergent structure of local agonistic networks is not modular but instead recurrently display a nested structure, with a core of highly interactive site-attached herbivores of the Pomacentridae family. Therefore, despite the increase in the number of species involved in agonistic interactions toward speciose communities, the network structure is conserved along the longitudinal richness gradient because local disputes are mostly driven by closely-related, functionally-similar species. These findings suggest that evolutionary and local processes interact in modulating reef fish agonistic behaviour and that fine-scale niche-partitioning can structure the ecological networks in marine ecosystems.     

Anti-inflammatory effect of octyl gallate in alveolar macrophages cells and mice with acute lung injury

Acute lung injury (ALI) is an inflammatory process, and has high incidence and mortality. ALI and the acute respiratory distress syndrome are two common complications worldwide that result in acute lung failure, sepsis, and death. Pro-inflammatory substances, such as cytokines and chemokines, are responsible for activating the body's defense mechanisms and usually mediate inflammatory processes. Therefore, the research of substances that decrease the uncontrolled response of organism is seen as potential for patients with ALI. Octyl gallate (OG) is a phenolic compound with therapeutic actions namely antimicrobial, antiviral, and antifungal. In this study, we evaluated its action on lipopolysaccharide (LPS)-activated alveolar macrophages RAW 264.7 cells and ALI in male mice. Our results demonstrated protective effects of OG in alveolar macrophages activated with LPS and mice with ALI. The OG treatment significantly decreased the inflammatory markers in both studies in vitro and in vivo. The data suggested that OG can act as an anti-inflammatory agent for ALI.     

Dissecting the mechanisms of environment sensitivity of smart probes for quantitative assessment of membrane properties

The plasma membrane, as a highly complex cell organelle, serves as a crucial platform for a multitude of cellular processes. Its collective biophysical properties are largely determined by the structural diversity of the different lipid species it accommodates. Therefore, a detailed investigation of biophysical properties of the plasma membrane is of utmost importance for a comprehensive understanding of biological processes occurring therein. During the past two decades, several environment-sensitive probes have been developed and become popular tools to investigate membrane properties. Although these probes are assumed to report on membrane order in similar ways, their individual mechanisms remain to be elucidated. In this study, using model membrane systems, we characterized the probes Pro12A, NR12S and NR12A in depth and examined their sensitivity to parameters with potential biological implications, such as the degree of lipid saturation, double bond position and configuration (cis versus trans), phospholipid headgroup and cholesterol content. Applying spectral imaging together with atomistic molecular dynamics simulations and time-dependent fluorescent shift analyses, we unravelled individual sensitivities of these probes to different biophysical properties, their distinct localizations and specific relaxation processes in membranes. Overall, Pro12A, NR12S and NR12A serve together as a toolbox with a wide range of applications allowing to select the most appropriate probe for each specific research question.     

Activity,habitat use,density, and reproductive biology of the crab-eating fox (Cerdocyon thous) and comparison with the pampas fox (Lycalopex gymnocercus) in a Restinga area in the southern Brazilian Atlantic Forest

The ecology and reproductive biology of the crab-eating fox (Cerdocyon thous) and the pampas fox (Lycalopex gymnocercus) were studied in Itapuã State Park, an Atlantic Forest fragment. In this study we describe their activity patterns (diel, lunar, and seasonal), reproductive period, density, spatial distribution, and habitat overlap. The crab-eating fox was more abundant than the pampas fox, occurring in all types of habitats and overlapping with the pampas fox only in the southern portion of the study area, covered by open vegetation. Both canid species presented nocturnal habits and C. thous showed no significant differences in activity among lunar phases or else year season. The density of C. thous was estimated to be 0.78 ind/km². The crab-eating fox reproduced once a year, generating pups during spring (October to December). In comparison with C. thous populations from lower-latitude regions the relatively low density and one reproductive event per year that we observed are probably related to a colder climate, shorter photoperiod, and shortage of food resources in the winter, characteristic of southern Brazil.     

Superoxide dismutase and glutathione reductase overexpression in wheat protoplast: photooxidative stress tolerance and changes in cellular redox state

In previous works, we have established a correlation between antioxidant system response and tolerance to drought, osmotic stress and photooxidative stress of different wheat cultivars with contrasting drought tolerance. In the present work, a protocol to obtain and transform wheat protoplasts was established. Transgenic protoplasts with Manganese Superoxide Dismutase (Mn-SOD) (E.C.: 1.15.1.1) and Glutathione Reductase (GR) (E.C.: 1.6.4.2) overexpression in chloroplasts were obtained, and their responses to photooxidative stress were characterized. Protoplasts with Mn-SOD or GR overexpression, showed different responses and tolerance to photooxidative stress. Protoplasts with Mn-SOD overexpression showed lower levels of oxidative damage, higher level of endogenous hydrogen peroxide and a great induction of total SOD and GR activities during photooxidative treatments. In protoplasts with GR overexpression the oxidative damage provoked by the photooxidative treatment was similar to control protoplasts, the GSH content and GSH/GSH + GSSG ratio were higher than control and Mn-SOD transformed protoplast, and total SOD and GR activities were not induced. Our results suggest that the differential responses and tolerance to photooxidative stress given by Mn-SOD or GR overexpression, also depend on the effects of these enzyme activities over the cellular redox state balance, which modulate the responses to photooxidative stress.     

Identification of the Schistosoma mansoni TNF-Alpha Receptor Gene and the Effect of Human TNF-Alpha on the Parasite Gene Expression Profile

Background

Schistosoma mansoni is the major causative agent of schistosomiasis. The parasite takes advantage of host signals to complete its development in the human body. Tumor necrosis factor-alpha (TNF-α) is a human cytokine involved in skin inflammatory responses, and although its effect on the adult parasite''s metabolism and egg-laying process has been previously described, a comprehensive assessment of the TNF-α pathway and its downstream molecular effects is lacking.

Methodology/Principal Findings

In the present work we describe a possible TNF-α receptor (TNFR) homolog gene in S. mansoni (SmTNFR). SmTNFR encodes a complete receptor sequence composed of 599 amino acids, and contains four cysteine-rich domains as described for TNFR members. Real-time RT-PCR experiments revealed that SmTNFR highest expression level is in cercariae, 3.5 (±0.7) times higher than in adult worms. Downstream members of the known human TNF-α pathway were identified by an in silico analysis, revealing a possible TNF-α signaling pathway in the parasite. In order to simulate parasite''s exposure to human cytokine during penetration of the skin, schistosomula were exposed to human TNF-α just 3 h after cercariae-to-schistosomula in vitro transformation, and large-scale gene expression measurements were performed with microarrays. A total of 548 genes with significantly altered expression were detected, when compared to control parasites. In addition, treatment of adult worms with TNF-α caused a significantly altered expression of 1857 genes. Interestingly, the set of genes altered in adults is different from that of schistosomula, with 58 genes in common, representing 3% of altered genes in adults and 11% in 3 h-old early schistosomula.

Conclusions/Significance

We describe the possible molecular elements and targets involved in human TNF-α effect on S. mansoni, highlighting the mechanism by which recently transformed schistosomula may sense and respond to this host mediator at the site of cercarial penetration into the skin.     

Early events in speciation: Cryptic species of Drosophila aldrichi

Understanding the earliest events in speciation remains a major challenge in evolutionary biology. Thus identifying species whose populations are beginning to diverge can provide useful systems to study the process of speciation. Drosophila aldrichi, a cactophilic fruit fly species with a broad distribution in North America, has long been assumed to be a single species owing to its morphological uniformity. While previous reports either of genetic divergence or reproductive isolation among different D. aldrichi strains have hinted at the existence of cryptic species, the evolutionary relationships of this species across its range have not been thoroughly investigated. Here we show that D. aldrichi actually is paraphyletic with respect to its closest relative, Drosophila wheeleri, and that divergent D. aldrichi lineages show complete hybrid male sterility when crossed. Our data support the interpretation that there are at least two species of D. aldrichi, making these flies particularly attractive for studies of speciation in an ecological and geographical context.     

The influence of 5-lipoxygenase on cigarette smoke-induced emphysema in mice

Background

Pulmonary emphysema is characterized by the loss of lung architecture. Our hypothesis is that the inhibition of 5-lipoxygenase (5-LO) production may be an important strategy to reduce inflammation, oxidative stress, and metalloproteinases in lung tissue resulting from cigarette smoke (CS)-induced emphysema.

Methods

5-LO knockout (129S2-Alox5^tm1Fun/J) and wild-type (WT) mice (129S2/SvPas) were exposed to CS for 60 days. Mice exposed to ambient air were used as Controls. Oxidative, inflammatory, and proteolytic markers were analyzed.

Results

The alveolar diameter was decreased in CS 5-LO^−/− mice when compared with the WT CS group. The CS exposure resulted in less pronounced pulmonary inflammation in the CS 5-LO^−/− group. The CS 5-LO^−/− group showed leukotriene B4 values comparable to those of the Control group. The expression of MMP-9 was decreased in the CS 5-LO^−/− group when compared with the CS WT group. The expression of superoxide dismutase, catalase, and glutathione peroxidase were decreased in the CS 5-LO^−/− group when compared with the Control group. The protein expression of nuclear factor (erythroid-derived 2)-like 2 was reduced in the CS 5-LO^−/− group when compared to the CS WT group.

Conclusion

In conclusion, we show for the first time that 5-LO deficiency protects 129S2 mice against emphysema caused by CS. We suggest that the main mechanism of pathogenesis in this model involves the imbalance between proteases and antiproteases, particularly the association between MMP-9 and TIMP-1.General significanceThis study demonstrates the influence of 5-LO mediated oxidative stress, inflammation, and proteolytic markers in CS exposed mice.