Phoma glomerata, a potential new threat to Italian inland waters

Non-indigenous crayfish species, carrier of the oomycete Aphanomyces astaci, are the most important threats to European crayfish species. However, other ectoparasite species have been reported to be the pathogen of aquatic organisms. As little is known about other potential pathogens carried by the red swamp crayfish Procambarus clarkii, a total of 86 individuals of this species was collected in Lake Trasimeno from June 2007 to 2008. Phoma glomerata, never recorded in Italy, colonised more than 65% of the captured crayfish. No significant differences in prevalence were recorded between sexes, among life stages and between soft- and hard-shelled crayfish. This Coelomycetes is the causal agent of many diseases in plants, animals and humans. These results may contribute to a better understanding of the implications of epibiontic microfungi on the invasive crayfish P. clarkii, for both ecological and sanitary purposes.     

Birth,death and horizontal transfer of the fumonisin biosynthetic gene cluster during the evolutionary diversification of Fusarium

Fumonisins are a family of carcinogenic secondary metabolites produced by members of the Fusarium fujikuroi species complex (FFSC) and rare strains of Fusarium oxysporum. In Fusarium, fumonisin biosynthetic genes (FUM) are clustered, and the cluster is uniform in gene organization. Here, sequence analyses indicated that the cluster exists in five different genomic contexts, defining five cluster types. In FUM gene genealogies, evolutionary relationships between fusaria with different cluster types were largely incongruent with species relationships inferred from primary‐metabolism (PM) gene genealogies, and FUM cluster types are not trans‐specific. In addition, synonymous site divergence analyses indicated that three FUM cluster types predate diversification of FFSC. The data are not consistent with balancing selection or interspecific hybridization, but they are consistent with two competing hypotheses: (i) multiple horizontal transfers of the cluster from unknown donors to FFSC recipients and (ii) cluster duplication and loss (birth and death). Furthermore, low levels of FUM gene divergence in F. bulbicola, an FFSC species, and F. oxysporum provide evidence for horizontal transfer of the cluster from the former, or a closely related species, to the latter. Thus, uniform gene organization within the FUM cluster belies a complex evolutionary history that has not always paralleled the evolution of Fusarium.     

Scale‐dependent influence of environmental variables on species distribution: a case study on five coastal benthic species in the Baltic Sea

Statistical modelling can be used to relate biological survey data to environmental factors, thereby providing a basis for predictive mapping of species or communities. Although environmental variables vary and influence biota at different scales, models are often fitted without discussion of how scale dependency influences the results. In this study, we analysed the relative importance of environmental factors for the distribution of aquatic species as a function of extent, using data on the cover of five common benthic species (four macrophytes and one animal), from 1731 sites along the Swedish Baltic Sea coast. We modelled the cover and distribution of the five species in relation to salinity, depth, slope, wave exposure and substrate in scale steps from 25 to 1500 km, and analysed the relative contribution of the environmental variables to each species model. The average total deviance explained by the models was generally quite high, and decreased with increasing scale for all macrophyte species, while it increased for the animal, the Baltic Sea blue mussel Mytilus edulis. The relative contribution of different environmental variables changed with scale, and responses also differed between species. The average contribution of salinity increased for all species when moving from local to Baltic Sea scale, and for the Baltic Sea blue mussel it was the single most important factor at the Baltic Sea scale. The average contribution of depth decreased with increasing scale for all species. However, regardless of scale, depth was the most important environmental factor to explain the distribution of all but one of the investigated macrophyte species. This shows that fine scale predictor variables can be of major importance also for species distribution models covering large areas.     

Residui di Leccete pure e miste sulla Murgia di Putignano

Summary

Purpose of this paper is to point out the residues of Quercus Ilex woods in the hilly region of Murgia di Putignano (Puglia) which lies inside the distribution area of Q. trojana, now the main wood-forming tree-species of this territory.

Fourteen different small Q. Ilex stands are mentioned, as marked on alleged map. One of them (n° 1 on the map) has been more carefully studied through a whole year, and all plants growing in it have been collected.     

PTPN2 Regulates Inflammasome Activation and Controls Onset of Intestinal Inflammation and Colon Cancer

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Cell type‐specific regulation of ciliary transition zone assembly in vertebrates

Ciliopathies are life‐threatening human diseases caused by defective cilia. They can often be traced back to mutations of genes encoding transition zone (TZ) proteins demonstrating that the understanding of TZ organisation is of paramount importance. The TZ consists of multimeric protein modules that are subject to a stringent assembly hierarchy. Previous reports place Rpgrip1l at the top of the TZ assembly hierarchy in Caenorhabditis elegans. By performing quantitative immunofluorescence studies in RPGRIP1L^?/? mouse embryos and human embryonic cells, we recognise a different situation in vertebrates in which Rpgrip1l deficiency affects TZ assembly in a cell type‐specific manner. In cell types in which the loss of Rpgrip1l alone does not affect all modules, additional truncation or removal of vertebrate‐specific Rpgrip1 results in an impairment of all modules. Consequently, Rpgrip1l and Rpgrip1 synergistically ensure the TZ composition in several vertebrate cell types, revealing a higher complexity of TZ assembly in vertebrates than in invertebrates.     

THE EVOLUTIONARY GENETICS AND DEVELOPMENTAL BASIS OF WING PATTERN VARIATION IN THE BUTTERFLY BICYCLUS ANYNANA

We have studied interactions between developmental processes and genetic variation for the eyespot color pattern on the adult dorsal forewing of the nymphalid butterfly, Bicyclus anynana. Truncation selection was applied in both an upward and a downward direction to the size of a single eyespot consisting of rings with wing scales of differing color pigments. High heritabilities resulted in rapid responses to selection yielding divergent lines with very large or very small eyespots. Strong correlated responses occurred in most of the other eyespots on each wing surface. The cells at the center of a presumptive eyespot (the “focus”) act in the early pupal stage to establish the adult wing pattern. The developmental fate of the scale cells within an eyespot is specified by the “signaling” properties of the focus and the “response” thresholds of the epidermis. The individual eyespots can be envisaged as developmental homologues. Grafting experiments performed with the eyespot foci of the selected lines showed that additive genetic variance exists for both the response and, in particular, the signaling components of the developmental system. The results are discussed in the context of how constraints on the evolution of this wing pattern may be related to the developmental organization.     

Characterization and transplantation of two neuronal cell lines with dopaminergic properties

Immortalized rat mesencephalic cells (1RB₃AN₂₇) produced dopamine (DA) at a level that was higher than produced by undifferentiated or differentiated murine neuroblastoma cells (NBP₂) in culture. Treatment of 1RB₃AN₂₇ and NBP₂ cells with a cAMP stimulating agent increased tyrosine hydroxylase (TH) activity and the intensity of immunostaining for the DA transporter protein (DAT). 1RB₃AN₂₇ cells were labelled with primary antibodies to neuron specific enolase (NSE) and nestin and exhibited very little or no labeling with anti-glial fibrillary acidic protein (GFAP). 1RB₃AN₂₇ cells exhibited β- and α-adrenoreceptors, and prostaglandin E₁ receptors, all of which were linked to adenylate cyclase (AC). Dopamine receptor (D₁) and cholinergic muscarinic receptors linked to AC were not detectable. The levels of PKCα and PKCβ isoforms were higher than those of PKCγ and PKCδ in 1RB₃AN₂₇ cells. The 1RB₃AN₂₇ cells were more effective in reducing the rate of methamphetamine-induced turning in rats with unilateral 6-OHDA lesion of the nigrostriatal system than differentiated NBP₂ cells. The grafted 1RB₃AN₂₇ were viable as determined by DiI labelling, but they did not divide and did not produce T-antigen protein; however, when these grafted cells were cultured in vitro, they resumed production of T-antigen and proliferated after the primary glia cells and neurons of host brain died due to maturation and subsequent degeneration. Examination of H&E stained sections of the grafted sites revealed no evidence of infiltration of inflammatory cells in the grafted area suggesting that these cells were not immunogenic. They also did not form tumors.     

High climate velocity and population fragmentation may constrain climate‐driven range shift of the key habitat former Fucus vesiculosus

Aim

The Baltic Sea forms a unique regional sea with its salinity gradient ranging from marine to nearly freshwater conditions. It is one of the most environmentally impacted brackish seas worldwide, and the low biodiversity makes it particularly sensitive to anthropogenic pressures including climate change. We applied a novel combination of models to predict the fate of one of the dominant foundation species in the Baltic Sea, the bladder wrack Fucus vesiculosus.

Location

The Baltic Sea.

Methods

We used a species distribution model to predict climate change‐induced displacement of F. vesiculosus and combined these projections with a biophysical model of dispersal and connectivity to explore whether the dispersal rate of locally adapted genotypes may match estimated climate velocities to recolonize the receding salinity gradient. In addition, we used a population dynamic model to assess possible effects of habitat fragmentation.

Results

The species distribution model showed that the habitat of F. vesiculosus is expected to dramatically shrink, mainly caused by the predicted reduction of salinity. In addition, the dispersal rate of locally adapted genotypes may not keep pace with estimated climate velocities rendering the recolonization of the receding salinity gradient more difficult. A simplistic model of population dynamics also indicated that the risk of local extinction may increase due to future habitat fragmentation.

Main conclusions

Results point to a significant risk of locally adapted genotypes being unable to shift their ranges sufficiently fast considering the restricted dispersal and long generation time. The worst scenario is that F. vesiculosus may disappear from large parts of the Baltic Sea before the end of this century with large effects on the biodiversity and ecosystem functioning. We finally discuss how to reduce this risk through conservation actions, including assisted colonization and assisted evolution.