Dogs discriminate between barks: The effect of context and identity of the caller

In the present study we explored whether dogs (Canis familiaris) are able to discriminate between conspecific barks emitted in different contexts recorded either from the same or different individuals. Playback experiments were conducted with dogs using barks as stimuli in a habituation–dishabituation paradigm. Barks were recorded in two contexts (stranger at the fence and when the dog was left alone) from different individuals. We found that dogs distinguished between barks emitted in these two contexts and were also able to discriminate between different individuals which were barking in the same context. These findings suggest that dog bark may carry context- and individual-specific information for the conspecifics.     

Convergent evolution and orphan genes in the Fur4p-like family and characterization of a general nucleoside transporter in Aspergillus nidulans

The function of seven paralogues phylogenetically related to the Saccharomyces cerevisiae Fur4p together with a number of functionally related transporters present in Aspergillus nidulans has been investigated. After deletion of the cognate genes we checked the incorporation of radiolabelled substrates, utilization of nitrogen sources, resistance to toxic analogues and supplementation of auxotrophies. FurA and FurD encode allantoin and uracil transporters respectively. No function was found for FurB, FurC, FurE, FurF and FurG. As we failed to identify Fur-related transporters for uridine, pyridoxine or thiamine, we deleted other possible candidates for these functions. A FCY2 -like gene carrying in its 5' UTR a putative thiamine pyrophosphate riboswitch, and which encodes a protein similar to the pyridoxine transporter of yeast (Tpn1p), does not encode either a major thiamine or a pyridoxine transporter. CntA, a member of the concentrative nucleoside transporter family, is a general nucleoside permease, while no function was found for PnpA, a member of the equilibrative transporter family. Phylogenetic analysis shows that within the ascomycetes, the same transport activity could be catalysed by totally unrelated proteins and that within the Fur subfamily convergent evolution towards uracil and allantoin transport activity has occurred at least three and two independent times respectively.     

Host Niches and Defensive Extended Phenotypes Structure Parasitoid Wasp Communities

Oak galls are spectacular extended phenotypes of gallwasp genes in host oak tissues and have evolved complex morphologies that serve, in part, to exclude parasitoid natural enemies.Parasitoids and their insect herbivore hosts have coevolved to produce diverse communities comprising about a third of all animal species. The factors structuring these communities, however, remain poorly understood. An emerging theme in community ecology is the need to consider the effects of host traits, shaped by both natural selection and phylogenetic history, on associated communities of natural enemies. Here we examine the impact of host traits and phylogenetic relatedness on 48 ecologically closed and species-rich communities of parasitoids attacking gall-inducing wasps on oaks. Gallwasps induce the development of spectacular and structurally complex galls whose species- and generation-specific morphologies are the extended phenotypes of gallwasp genes. All the associated natural enemies attack their concealed hosts through gall tissues, and several structural gall traits have been shown to enhance defence against parasitoid attack. Here we explore the significance of these and other host traits in predicting variation in parasitoid community structure across gallwasp species. In particular, we test the “Enemy Hypothesis,” which predicts that galls with similar morphology will exclude similar sets of parasitoids and therefore have similar parasitoid communities. Having controlled for phylogenetic patterning in host traits and communities, we found significant correlations between parasitoid community structure and several gall structural traits (toughness, hairiness, stickiness), supporting the Enemy Hypothesis. Parasitoid community structure was also consistently predicted by components of the hosts'' spatiotemporal niche, particularly host oak taxonomy and gall location (e.g., leaf versus bud versus seed). The combined explanatory power of structural and spatiotemporal traits on community structure can be high, reaching 62% in one analysis. The observed patterns derive mainly from partial niche specialisation of highly generalist parasitoids with broad host ranges (>20 hosts), rather than strict separation of enemies with narrower host ranges, and so may contribute to maintenance of the richness of generalist parasitoids in gallwasp communities. Though evolutionary escape from parasitoids might most effectively be achieved via changes in host oak taxon, extreme conservatism in this trait for gallwasps suggests that selection is more likely to have acted on gall morphology and location. Any escape from parasitoids associated with evolutionary shifts in these traits has probably only been transient, however, due to subsequent recruitment of parasitoid species already attacking other host galls with similar trait combinations.     

Influence of in vitro and in vivo insulin treatment on the hormone (histamine, serotonin, endorphin and triiodothyronine) content of thymus and spleen cells

Thymic and spleen cells were treated in vitro or in vivo with insulin. The in vitro treatments were done with 10(-6), 10(-9), 10(-12) and 10(-15) M concentrations for 30 min and after that histamine, serotonin, endorphin and triiodothyronine (T3) content of the cells were detected by using antibodies to the hormones and flow cytometry as well as confocal microscopy. For in vivo treatment 1 IU/kg insulin was given for adult rats and 1 h after that the target hormone contents were determined by the same manner. Histamine and T3 content radically decreased in the thymus after in vitro treatment independent on the insulin concentrations administered. In vivo treatment halved histamine and T3 content. Serotonin content also decreased after in vitro treatment with the two higher concentrations, however the in vivo treatment did not cause a change. Histamine content was elevated after in vitro treatment in the spleen, independent on the insulin concentration. Endorphin level was not influenced at all. The experiments demonstrate that insulin is a factor which regulates the content (production, storage, secretion?) of some immunologically important molecules of the immune cells. Since each hormone molecule studied has important immunomodulatory role, the experiment points to the indirect immunomodulatory role of insulin.     

Optimalized transient transfection of chondrogenic primary cell cultures

We aimed to find a transfection method which provides high efficiency with minimal cytotoxic and/or apoptotic effects for gene transfer into multilayer primary chondrogenic cell cultures. The pEGFP-C1 plasmid was introduced into the cell culture and the efficiency of transformation quantified by GFP fluorescence; the resulting nucleofection was effective but resulted in severe apoptosis. Two liposomal reagents designed to allow transfection into adherent cells did not deliver the plasmids sufficiently and cartilage formation did not occur. In addition, a third liposomal compound, recommended for transfection into either adherent or suspension cell cultures, lead to acceptable transfection efficiency but no cartilage formation. When an amphiphilic reagent was used however, there was acceptable transfection efficiency as well as cartilage formation. The viability of the cells which were transfected using the amphiphilic reagent remained unaffected but proliferation was severely diminished, particularly in the presence of GFP. In addition, the amount of cartilage decreased when GFP was expressed, despite unchanged levels of mRNAs of sox9 and aggrecan core protein, factors reflecting on the efficiency of chondrogenesis. Overexpression of both the constitutively active delta and gamma isoforms of catalytic subunit of calcineurin, a protein phosphatase described as a positive regulator of chondrogenesis, decreased protein level of Sox9 and subsequent cartilage formation. In conclusion, we found that amphiphilic reagent applied prior to the adhesion of cells provides a useful means to transfer plasmids to primary differentiating chondrogenic cells.     

Construction of a dense SNP map of a highly heterozygous diploid potato population and QTL analysis of tuber shape and eye depth

Key message

Generation of a dense SNP-based linkage map of a diploid potato population and identification of major QTLs for tuber shape and eye depth on chromosomes 2 and 10.

Abstract

This paper reports the construction of a genetic map of a highly heterozygous full-sib diploid potato population (06H1) based on the use of a set of 8,303 single nucleotide polymorphism (SNP) markers. The map contains 1,355 distinct loci and 2,157 SNPs, 802 of which co-segregate with other markers. We find high levels of collinearity between the 12 chromosomal maps with a recently improved version of the potato genome assembly, with the expected genetic clustering in centromeric regions. The linkage maps are used in combination with highly detailed phenotypic assessments conducted over two growing seasons to perform quantitative trait loci analysis of two important potato traits, tuber shape and eye depth. The major loci segregating for tuber shape in 06H1 map to loci on chromosomes 2 and 10, with smaller effects mapping to three other chromosomes. A major locus for tuber eye depth co-locates with the tuber shape locus on chromosome 10. To assess when tuber shape is established in the developing tuber, we have performed staged observations of tuber formation. Our observations suggest that tuber shape is determined very early in tuber development.     

Effect of different concentrations of serotonin, histamine and insulin on the hormone (serotonin and ACTH) production of Tetrahymena in nutrient-free physiological milieu

Cell populations of Tetrahymena pyriformisGL were kept in nutrient-free (Losina) milieu and treated with different (10⁻⁶–10⁻²¹ M) concentrations of serotonin, histamine or insulin for 30 min. Following that the hormone (serotonin and adrenocorticotropin (ACTH) content of the cells were measured by immunocytochemical flow cytometric method. Serotonin reduced histamine when applied in 10⁻¹² and 10⁻¹⁵ M concentrations, while elevated ACTH levels when applied in 10⁻⁶, 10⁻⁹ and 10⁻²¹ M concentrations. Histamine reduced serotonin concentration at 10⁻⁹–10⁻²¹ M concentrations and increased ACTH in 10⁻⁶ M. Insulin elevated both hormones’ content in each concentration except at 10⁻¹² M. The results demonstrate that (1) in nutrient-free conditions the hormonal effects differ from that of nutrient-rich (tryptone + yeast) condition; (2) there is an optimal hormone concentration, which causes the strongest effect and this is different for each hormones; (3) the hormone receptors of Tetrahymena are very sensitive; as they react to zeptomolar concentrations. Such small concentration is even more effective than higher ones. Since hormones must become highly diluted in the natural environment of Tetrahymena, it seems that such low concentrations are the actual physiological concentrations.     

Where is the unseen fungal diversity hidden? A study of Mortierella reveals a large contribution of reference collections to the identification of fungal environmental sequences

? Estimation of the proportion of undescribed fungal taxa is an issue that has remained unresolved for many decades. Several very different estimates have been published, and the relative contributions of traditional taxonomic and next-generation sequencing (NGS) techniques to species discovery have also been called into question recently. ? Here, we addressed the question of what proportion of hitherto unidentifiable molecular operational taxonomic units (MOTUs) have already been described but not sequenced, and how many of them represent truly undescribed lineages. We accomplished this by modeling the effects of increasing type strain sequencing effort on the number of identifiable MOTUs of the widespread soil fungus Mortierella. ? We found a nearly linear relationship between the number of type strains sequenced and the number of identifiable MOTUs. Using this relationship, we made predictions about the total number of Mortierella species and found that it was very close to the number of described species in Mortierella. ? These results suggest that the unusually high number of unidentifiable MOTUs in environmental sequencing projects can be, at least in some fungal groups, ascribed to a lag in type strain and specimen sequencing rather than to a high number of undescribed species.     

mGluR7 Genetics and Alcohol: Intersection Yields Clues for Addiction

Development of addiction to alcohol or other substances can be attributed in part to exposure-dependent modifications at synaptic efficacy leading to an organism which functions at an altered homeostatic setpoint. Genetic factors may also influence setpoints and the stability of the homeostatic system of an organism. Quantitative genetic analysis of voluntary alcohol drinking, and mapping of the involved genes in the quasi-congenic Recombinant QTL Introgression strain system, identified Eac2 as a Quantitative Trait Locus (QTL) on mouse chromosome 6 which explained 18% of the variance with an effect size of 2.09 g/kg/day alcohol consumption, and Grm7 as a quantitative trait gene underlying Eac2 [Vadasz et al. in Neurochem Res 32:1099–1112, 100, Genomics 90:690–702, 102]. In earlier studies, the product of Grm7 mGluR7, a G protein-coupled receptor, has been implicated in stress systems [Mitsukawa et al. in Proc Natl Acad Sci USA 102:18712–18717, 63], anxiety-like behaviors [Cryan et al. in Eur J Neurosci 17:2409–2417, 14], memory [Holscher et al. in Learn Mem 12:450–455, 26], and psychiatric disorders (e.g., [Mick et al. in Am J Med Genet B Neuropsychiatr Genet 147B:1412–1418, 61; Ohtsuki et al. in Schizophr Res 101:9–16, 72; Pergadia et al. in Paper presented at the 38th Annual Meeting of the Behavior Genetics Association, Louisville, Kentucky, USA, 76]. Here, in experiments with mice, we show that (1) Grm7 knockout mice express increased alcohol consumption, (2) sub-congenic, and congenic mice carrying a Grm7 variant characterized by higher Grm7 mRNA drink less alcohol, and show a tendency for higher circadian dark phase motor activity in a wheel running paradigm, respectively, and (3) there are significant genetic differences in Grm7 mRNA abundance in the mouse brain between congenic and background mice identifying brain areas whose function is implicated in addiction related processes. We hypothesize that metabotropic glutamate receptors may function as regulators of homeostasis, and Grm7 (mGluR7) is involved in multiple processes (including stress, circadian activity, reward control, memory, etc.) which interact with substance use and the development of addiction. In conclusion, we suggest that mGluR7 is a significant new therapeutic target in addiction and related neurobehavioral disorders.