Novel Galanin Receptor Subtype Specific Ligand in Depression Like Behavior

Neuropeptide galanin and its three receptors, galanin receptor type 1–galanin receptor type 3, are known to be involved in the regulation of numerous psychological processes, including depression. Studies have suggested that stimulation of galanin receptor type 2 (GalR2) leads to attenuation of the depression-like behavior in animals. However, due to the lack of highly selective galanin subtype specific ligands the involvement of different receptors in depression-like behavior is yet not fully known. In the present study we introduce a novel GalR2 selective agonist and demonstrate its ability to produce actions consistent with theorized GalR2 functions and analogous to that of the anti-depressant, imipramine.     

Microfragmentation concept explains non-positive environmental heterogeneity–diversity relationships

Although recent studies have revealed that the relationship between diversity and environmental heterogeneity is not always positive, as classical niche theory predicts, scientists have had difficulty interpreting these results from an ecological perspective. We propose a new concept—microfragmentation—to explain how small-scale heterogeneity can have neutral or even negative effect on species diversity. We define microfragmentation as a community level process of splitting habitat into a more heterogeneous environment that can have non-positive effects on the diversity through habitat loss and subsequent isolation. We provide support for the microfragmentation concept with results from spatially explicit heterogeneity–diversity model simulations, in which varying sets of species (with different ratios of specialist and generalist species) were modeled at different levels of configurational heterogeneity (meaning that only the habitat structure was changed, not its composition). Our results indicate that environmental heterogeneity can affect community diversity in the same way as fragmentation at the landscape level. Although generalist species might not be seriously affected by microfragmentation, the persistence of specialist species can be seriously disturbed by small-scale patchiness. The microfragmentation concept provides new insight into community level diversity dynamics and can influence conservation and management strategies.     

Tree diversity and species identity effects on soil fungi,protists and animals are context dependent

Plant species richness and the presence of certain influential species (sampling effect) drive the stability and functionality of ecosystems as well as primary production and biomass of consumers. However, little is known about these floristic effects on richness and community composition of soil biota in forest habitats owing to methodological constraints. We developed a DNA metabarcoding approach to identify the major eukaryote groups directly from soil with roughly species-level resolution. Using this method, we examined the effects of tree diversity and individual tree species on soil microbial biomass and taxonomic richness of soil biota in two experimental study systems in Finland and Estonia and accounted for edaphic variables and spatial autocorrelation. Our analyses revealed that the effects of tree diversity and individual species on soil biota are largely context dependent. Multiple regression and structural equation modelling suggested that biomass, soil pH, nutrients and tree species directly affect richness of different taxonomic groups. The community composition of most soil organisms was strongly correlated due to similar response to environmental predictors rather than causal relationships. On a local scale, soil resources and tree species have stronger effect on diversity of soil biota than tree species richness per se.     

Immune response is energetically costly in white cabbage butterfly pupae

Parasite-driven coevolution has led hosts to develop a complicated and potentially costly defence machinery, consisting mainly of the immune system. Despite the evidence for the trade-offs between immune function and life-history traits, it is still obscure how the costs of using and maintaining the immune function are paid. We tested whether immune challenge is energetically costly for white cabbage butterfly (Pieris brassicae L.) diapausing pupa. Individuals challenged with nylon implant raised their standard metabolic rate nearly 8% compared to the controls. Hence, costs of activation of immune system in insect pupa can be expressed in energetic currency.     

Factor X activator from Vipera lebetina venom is synthesized from different genes

Vipera lebetina venom contains specific coagulant Factor X activator (VLFXA) that cleaves the Arg52-Ile53 bond in the heavy chain of human factor X. VLFXA is a glycoprotein that is composed of a heavy chain (HC) and two light chains (LC) linked by disulfide bonds. The complete amino acid sequences of the three chains of the factor X activator from V. lebetina snake venom are deduced from the nucleotide sequences of cDNAs encoding these chains. The full-length cDNA (2347 bp) sequence of the HC encodes an open reading frame (ORF) of 612 amino acids that includes signal peptide, propeptide and mature metalloproteinase with disintegrin-like and cysteine-rich domains. The light chain LC1 contains 123 and LC2 135 amino acid residues. Both light chains belong to the class of C-type lectin-like proteins. The N-termini of VLFXA chains and inner sequences of peptide fragments detected by liquid chromatography-electrospray ionization tandem mass spectrometry (LC MS/MS) from protein sequence are 100% identical to the sequences deduced from the cDNA. The molecular masses of tryptic fragments of VLFXA chains analyzed by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) also confirm the protein sequences deduced from the cDNAs. These are the first cloned factor X activator heavy and light chains. We demonstrate that the heavy and light chains are synthesized from different genes.     

When not to avoid inbreeding

Avoidance of incestuous matings is widely reported across many animal taxa, and the adaptive value of such behavior is explained through inbreeding depression. However, an old and somewhat neglected theoretical result predicts that inbred matings offer another, positive effect on the inclusive fitness of parents: an individual who mates with a relative will help that relative to spread genes identical by descent. This benefit can be substantial, if the additional mating achieved by the relative does not harm his mating success otherwise, and in the context of selfing in plants the phenomenon is well known. Here, we develop a model that derives expected values of inbreeding tolerance, that is, the magnitude of inbreeding depression that is required to make individuals avoid inbreeding, for different animal life histories and parental investment patterns. We also distinguish between simultaneous and sequential mate choice, and show that inbreeding tolerance should often be remarkably high in the latter scenario in particular, although egalitarian parental care will lead to lower tolerance. There is a mismatch between theory and data: the almost complete lack of cases where individuals prefer to mate incestuously is at odds with a large overlap between the predicted range of inbreeding tolerance and estimates of inbreeding depression found in nature. We discuss four different solutions to this enigma, and suggest that inbreeding tolerance, where it is found, should not always be attributed to a simple constraint that has prevented finding any other mate.     

Anthropogenic disturbance equalizes diversity levels in arbuscular mycorrhizal fungal communities

The arbuscular mycorrhizal (AM) symbiosis is a key plant–microbe interaction in sustainable functioning ecosystems. Increasing anthropogenic disturbance poses a threat to AM fungal communities worldwide, but there is little empirical evidence about its potential negative consequences. In this global study, we sequenced AM fungal DNA in soil samples collected from pairs of natural (undisturbed) and anthropogenic (disturbed) plots in two ecosystem types (10 naturally wooded and six naturally unwooded ecosystems). We found that ecosystem type had stronger directional effects than anthropogenic disturbance on AM fungal alpha and beta diversity. However, disturbance increased alpha and beta diversity at sites where natural diversity was low and decreased diversity at sites where natural diversity was high. Cultured AM fungal taxa were more prevalent in anthropogenic than natural plots, probably due to their efficient colonization strategies and ability to recover from disturbance. We conclude that anthropogenic disturbance does not have a consistent directional effect on AM fungal diversity; rather, disturbance equalizes levels of diversity at large scales and causes changes in community functional structure.     

Novel galanin receptor subtype specific ligands in feeding regulation

Galanin a 29/30-residue neuropeptide has been implicated in several functions in the central nervous system, including the regulation of food consumption. Galanin and its analogues administered intraventricularly or into the hypothalamic region of brain have been shown to reliably and robustly stimulate the consumption of food in sated rodents. Three galanin receptor subtypes have been isolated, all present in the hypothalamus, but little is known about their specific role in mediating this acute feeding response. Presently, we introduce several novel GalR2 selective agonists and then compare the most selective of these novel GalR2 subtype selective agonists to known GalR1 selective agonist M617 for their ability to stimulate acute consumption of several foods shown to be stimulated by central administration of galanin. GalR1 selective agonist M617 markedly stimulated acute consumption of high-fat milk, but neither GalR2 selective agonist affected either high-fat milk or cookie mash intake. The present results are consistent with the involvement of GalR1 in mediating the acute feeding consumption by galanin and suggest an approach applicable to exploring galanin receptor specificity in normal and abnormal behavior and physiology.     

Molecular analysis confirms that Botryodontia millavensis and Oxyporus philadelphi are conspecific

The aim of the present study is to elucidate if Oxyporus philadelphi (Parmasto) Ryvarden and Botryodontia millavensis (Bourdot & Galzin) Duhem & H. Michel are conspecific, as suggested by their similar morphology. The analysis of ribosomal DNA ITS sequences indicate that the specimens of O. philadelphi and B. millavensis belong to a single species. The species is closely related to the type species (B. cirrata) of the genus Botryodontia, and therefore the name B. millavensis should currently be used for this taxon. Botryodontia millavensis grows on a wide selection of host species—Juniperus communis, Philadelphus coronarius, Picea abies, Fraxinus excelsior, Lonicera sp., J. turcomanica—and is distributed widely in temperate Eurasia.