Nuclear import and export of plant virus proteins and genomes

Nuclear import and export are crucial processes for any eukaryotic cell, as they govern substrate exchange between the nucleus and the cytoplasm. Proteins involved in the nuclear transport network are generally conserved among eukaryotes, from yeast and fungi to animals and plants. Various pathogens, including some plant viruses, need to enter the host nucleus to gain access to its replication machinery or to integrate their DNA into the host genome; the newly replicated viral genomes then need to exit the nucleus to spread between host cells. To gain the ability to enter and exit the nucleus, these pathogens encode proteins that recognize cellular nuclear transport receptors and utilize the host's nuclear import and export pathways. Here, we review and discuss our current knowledge about the molecular mechanisms by which plant viruses find their way into and out of the host cell nucleus.     

Building Bridges and Traveling through Time: Ethics, Practice, and Priorities in the Second Moscow International Visual Anthropology Film Festival

International film festivals are entangled spaces in which filmmakers and audiences negotiate aesthetic, ethical, political, and practical traditions and communities. This review of the Second Moscow International Visual Anthropology Film Festival explores some of the differences in ethics, practice, and priorities of anthropological filmmaking between Russia and the West. By providing a brief history of Soviet anthropology and a discussion of the festival's main themes, this review explores some of the historic and contemporary influences shaping the development of (one particular strain of) visual anthropology in post-Soviet Russia.     

Parasitoid genus‐specific manipulation of orb‐web host spiders (Araneae,Araneidae)

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Geographic patterns of genetic differentiation and plumage colour variation are different in the pied flycatcher (Ficedula hypoleuca)

The pied flycatcher is one of the most phenotypically variable bird species in Europe. The geographic variation in phenotypes has often been attributed to spatial variation in selection regimes that is associated with the presence or absence of the congeneric collared flycatcher. Spatial variation in phenotypes could however also be generated by spatially restricted gene flow and genetic drift. We examined the genetic population structure of pied flycatchers across the breeding range and applied the phenotypic Q _ST ( P _ST)– F _ST approach to detect indirect signals of divergent selection on dorsal plumage colouration in pied flycatcher males. Allelic frequencies at neutral markers were found to significantly differ among populations breeding in central and southern Europe whereas northerly breeding pied flycatchers were found to be one apparently panmictic group of individuals. Pairwise differences between phenotypic ( P _ST) and neutral genetic distances ( F _ST) were positively correlated after removing the most differentiated Spanish and Swiss populations from the analysis, suggesting that genetic drift may have contributed to the observed phenotypic differentiation in some parts of the pied flycatcher breeding range. Differentiation in dorsal plumage colouration however greatly exceeded that observed at neutral genetic markers, which indicates that the observed pattern of phenotypic differentiation is unlikely to be solely maintained by restricted gene flow and genetic drift.     

Over‐expression of bacterial γ‐glutamylcysteine synthetase (GSH1) in plastids affects photosynthesis,growth and sulphur metabolism in poplar (Populus tremula × Populus alba) dependent on the resulting γ‐glutamylcysteine and glutathione levels

We compared three transgenic poplar lines over‐expressing the bacterial γ‐glutamylcysteine synthetase (GSH1) targeted to plastids. Lines Lggs6 and Lggs12 have two copies, while line Lggs20 has three copies of the transgene. The three lines differ in their expression levels of the transgene and in the accumulation of γ‐glutamylcysteine (γ‐EC) and glutathione (GSH) in leaves, roots and phloem exudates. The lowest transgene expression level was observed in line Lggs6 which showed an increased growth, an enhanced rate of photosynthesis and a decreased excitation pressure (1‐qP). The latter typically represents a lower reduction state of the plastoquinone pool, and thereby facilitates electron flow along the electron transport chain. Line Lggs12 showed the highest transgene expression level, highest γ‐EC accumulation in leaves and highest GSH enrichment in phloem exudates and roots. This line also exhibited a reduced growth, and after a prolonged growth of 4.5 months, symptoms of leaf injury. Decreased maximum quantum yield (F_v/F_m) indicated down‐regulation of photosystem II reaction centre (PSII RC), which correlates with decreased PSII RC protein D1 (PsbA) and diminished light‐harvesting complex (Lhcb1). Potential effects of changes in chloroplastic and cytosolic GSH contents on photosynthesis, growth and the whole‐plant sulphur nutrition are discussed for each line.     

Separating Components of the Detection Process With Combined Methods: An Example With Northern Bobwhite

Abstract: There are various methods of estimating detection probabilities for avian point counts. Distance and multiple-observer methods require the sometimes unlikely assumption that all birds in the population are available (i.e., sing or are visible) during a count, but the time-of-detection method allows for the possibility that some birds are unavailable during the count. We combined the dependent double-observer method with the time-of-detection method and obtained field-based estimates of the components of detection probability for northern bobwhite (Colinus virginianus). Our approach was a special case of Pollock's robust capture-recapture design where the probability that a bird does not sing is analogous to the probability that an animal is a temporary emigrant. Top models indicated that observers' detection probabilities were similar (0.78–0.84) if bobwhite were available, but bobwhite only had an approximately 0.61 probability of being available during a 2.5-minute sampling interval. Additionally, observers' detection probabilities increased substantially after the initial encounter with an individual bobwhite (analogous to a trap-happy response on the part of the observer). A simulated data set revealed that the combined method was precise when availability and detection given availability were substantially lower. Combined methods approaches can provide critical information for researchers and land managers to make decisions regarding survey length and personnel requirements for point-count-based surveys.     

Attachment forces of pea aphids (Acyrthosiphon pisum) on different legume species

1. Sympatric populations of insects adapted to different host plants are good model systems not only to study how they adapt to the chemistry of their food plant, but also to investigate whether morphological modifications evolved enabling them to live successfully on a certain plant species. 2. The pea aphid, Acyrthosiphon pisum (Harris) encompasses at least 11 genetically distinct sympatric host races, each showing a preference for a certain legume species. The leaflet surfaces of these legumes differ considerably in their wax coverage. 3. It was investigated whether the attachment structures of three pea aphid genotypes from different host races are adapted to the different surface properties of their host plants and whether they show differences in their attachment ability on the respective host and non‐host plants. 4. The surface morphology of plants and aphid tarsi was examined using SEM (scanning electron microscopy). The ability of the aphids to walk on specific surfaces was tested using traction force measurements. 5. The presence of wax blooms on the leaflets lowers the aphids' attachment ability considerably and diminishes their subsequent attachment on ‘neutral’ surfaces like glass. The pea aphid host races differ in their ability to walk on certain surfaces. However, the genotype from the adapted aphid host race was not necessarily the one with the best walking performance on their host plant. All aphids, regardless of the original host plant, were most efficient on the neutral control surface glass. The general host plant Vicia faba was the plant with the most favourable surface for all aphid host races.     

Cluster biodiversity as a multidimensional structure evolution strategy: checkerspot butterflies of the group Euphydryas aurinia (Rottemburg, 1775) (Lepidoptera: Nymphalidae)

In the present paper, we explore the evolution of cluster structure in closely related species in the Euphydryas aurinia complex based on morphological (wing pattern, genital armatures) and molecular (cytochrome c oxidase subunit I) characters. Male genitalia differ in the length and shape of the uncus, harpe and juxta branches, by the shape of some parts of the phallus, and by the amount of spikes on the ventral section of the valva. The main trends in the vertical distribution of the E. aurinia group are dwarfism with increasing altitude, coupled with enlargement of paler and darker‐coloured elements of the wing pattern, increasing the overall contrast. Unlike the Euphydryas maturna, the E. aurinia complex forms many local populations specialized under different ecological conditions, probably affected by different evolutionary scenarios. The phylogenetic analysis of the group reveals two ecologically distinct subgroups: one associated with the boreal forest‐mesophyllic meadow biome and one associated with the xeromesophyllic steppe biome. Within each group, two major ecological strategies have evolved in parallel: montane and lowland. Based on the results of the analyses, we revise the nomenclature as follows: E. aurinia pyrenesdebilis (Verity, 1928), stat. rev. (= debilis Oberthür, 1909, syn.n. , nomen nudum), E. aurinia bulgarica (Fruhstorfer, 1916), stat. rev. , E. aurinia provincialis (Boisduval, 1828), stat. rev. and E. beckeri (Lederer, 1853), stat. rev. The following name‐bearing types are designated: neotype of Papilio aurinia Rottemburg, 1775, neotype of Papilio merope de Prunner, 1798, lectotype of Melitaea beckeri Lederer, 1853, and lectotype of Melitaea aurinia banghaasi Seitz, 1908. All name‐bearing types are figured. A new subspecies, Euphydryas laeta ostracon Korb, Bolshakov, Fric, ssp.n. , is described (type locality by holotype data: Kazakhstan, Vostochno‐Kazakhstanskaya Oblast, Shemonaikha).