PROTEIN RETENTION IN THE ENDOPLASMIC RETICULUM OF INSECT CELLS IS NOT COMPROMISED BY BACULOVIRUS INFECTION

High level expression of the major auxin-binding protein (ABP1) from maize (Zea maysL.) has been used to demonstrate that the machinery for retaining proteins in the endoplasmic reticulum (ER) of insect cells functions efficiently throughout the baculovirus infection cycle. Immuno-localization showed wild-type ABP1 (ABP1-KDEL) to be targeted to the lumen of the ER, in accordance with its signal peptide and carboxyterminal KDEL ER-retention signal. The protein accumulated in dilations of the ER, and none was detected at the cell surface. Immunoblotting of concentrated culture medium confirmed that ABP1-KDEL was not secreted at a detectable level. In contrast, when the carboxyterminus was mutated to KEQL, secretion of the baculovirus-expressed protein was readily detected. Immunolocalization and immunoblotting demonstrated that a high proportion of the ABP1-KEQL protein was secreted at the cell surface and into the culture medium. The data demonstrate that the ER of insect cells has a great capacity to retain proteins and that this property is largely unaffected by the cellular disruption caused by baculovirus replication.     

The distributions of a wide range of taxonomic groups are expanding polewards

Evidence is accumulating of shifts in species' distributions during recent climate warming. However, most of this information comes predominantly from studies of a relatively small selection of taxa (i.e., plants, birds and butterflies), which may not be representative of biodiversity as a whole. Using data from less well‐studied groups, we show that a wide variety of vertebrate and invertebrate species have moved northwards and uphill in Britain over approximately 25 years, mirroring, and in some cases exceeding, the responses of better‐known groups.     

Nicotiana tabacum callus studies. X. ABA increases resistance to cold damage

The effects of cis. trans abscisic acid on response to chilling was investigated in callused Nicotiana tabacum L. pith explants. Explants pretreated with 10^-4M ABA underwent approximately 50% less cellular leakage when chilled at 2°C under short-day conditions for 10 d than the comparable non-treated tissue. Growth in terms of fresh and dry weights, although poor in comparison to non-chilled (20°C, long days) treatments, was more than twice that of the non-ABA-treated material. On an absolute dry weight basis proline content increased on chilling from 0.7 to 3.4 mg g^-1 in non-ABA-treated explants, but rose to nearly 17 mg g^-1 in the tissue treated with ABA. Only in the case of cold-hardened. ABA-treated tissue could some cells survive subzero temperatures and regenerate callus again. It is suggested that at least part of the ameliorating effects of ABA result from an increase in the level of proline.     

Double-Binds in the Pursuit of Prosperity: Gulf Oil in Bantry Bay

Double-bind theory is applied to the concept of hegemony in this paper in order to analyse the dependency of a small community (Bantry Bay in Ireland) upon a multinational corporation (Gulf Oil). The implications for state policy of this relationship are then considered. The argument is that the dispensation of development as patronage in the form of industrial projects provided to needy communities puts such communities in an invidious predicament. The result is that they become ambivalent advocates of the interests of multinationals in the defence of their own.     

Large‐scale migration synchrony between parasitoids and their host

1. Parasitoids are a valuable group for conservation biological control. In their role as regulators of aphid pests, it is critical that their lifecycle is synchronised with their hosts in both space and time. This is because a synchronised parasitoid community is more likely to strengthen the overall conservation biological control effect, thus damping aphid numbers and preventing potential outbreaks. One component of this host–parasitoid system was examined, that of migration, and the hypothesis that peak summer parasitoid and host migrations are synchronised in time was tested. 2. Sitobion avenae Fabricius and six associated parasitoids were sampled from 1976 to 2013 using 12.2‐m suction‐traps from two sites in Southern England. The relationship between peak weekly S. avenae counts and their parasitoids was quantified. 3. Simple regression models showed that the response of the peak parasitoids to the host was positive: generally, more parasitoids migrated with increasing numbers of aphids. Further, when averaged over time, the parasitoid migration peak date corresponded with the aphid migration peak. The co‐occurrence of the peaks was between 51% and 64%. However, the summer peak in aphid migration is not steadily shifting forward with time unlike spring first flights of aphids. Cross‐correlation analysis showed that there were no between‐year lagged effects of aphids on parasitoids. 4. These results demonstrate that the peak in migration phenology between host and parasitoid is broadly synchronised within a season. Because the threshold temperature for flight (> 12 °C) was almost always exceeded in summer, the synchronising agent is likely to be crop senescence, not temperature. Studies are needed to assess the effects of climate change on the mismatch potential between parasitoids and their hosts.     

Cranial morphology of the California vole (Microtus californicus,Cricetidae) in a contact zone

Zones of contact between divergent biological forms within or between species are critical to the study of speciation. How characters flow across contact zones can be informative of the speciation process. To better understand this phenomenon in a mammal, we investigated cranial shape change in a contact zone between northern and southern phylogeographical groups of California voles (Microtus californicus). We took 12 linear measurements of skulls, one measurement of the mandible, and coded the presence and absence of two skull foramina for 427 specimens. In multivariate analyses, skulls within parental regions were correctly assigned more than 90% of the time. In the contact zone, 49% were classified as northern and 51% as southern, with a bimodal distribution of posterior probability values. Foraminal patterns in the contact zone were intermediate between northern and southern regions. A cline analysis for coastal populations suggested a similar centre for mitochondrial and nuclear markers, although a centre for the morphological data was offset. Cranial morphology indicates an intermediate area with overlap between the two regions, as suggested by the molecular data, with a pattern distinct from mitochondrial DNA or nuclear DNA markers. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 264–283.     

Relationships between phenology,radiation and precipitation in the Amazon region

In tropical areas, Dynamic Global Vegetation Models (DGVMs) still have deficiencies in simulating the timing of vegetation phenology. To start addressing this problem, standard Fourier‐based methods are applied to aerosol screened monthly remotely sensed phenology time series (Enhanced Vegetation Index, EVI) and two major driving factors of phenology: solar radiation and precipitation (for March 2000 through December 2006 over northern South America). At 1 × 1 km scale using, power (or variance) spectra on good quality aerosol screened time series, annual cycles in EVI are detected across 58.24% of the study area, the strongest (largest amplitude) occurring in the savanna. Terra Firme forest have weak but significant annual cycles in comparison with savannas because of the heterogeneity of vegetation and nonsynchronous phenological events within 1 × 1 km scale pixels. Significant annual cycles for radiation and precipitation account for 86% and 90% of the region, respectively, with different spatial patterns to phenology. Cross‐spectral analysis was used to compare separately radiation with phenology/EVI, precipitation with phenology/EVI and radiation with precipitation. Overall the majority of the Terra Firme forest appears to have radiation as the driver of phenology (either radiation is in phase or leading phenology/EVI at the annual scale). These results are in agreement with previous research, although in Acre, central and eastern Peru and northern Bolivia there is a coexistence of ‘in phase’ precipitation over Terra Firme forest. In contrast in most areas of savanna precipitation appears to be a driver and savanna areas experiencing an inverse (antiphase) relationship between radiation and phenology is consistent with inhibited grassland growth due to soil moisture limitation. The resulting maps provide a better spatial understanding of phenology–driver relationships offering a bench mark to parameterize ecological models.     

Assessing the effect of elevated carbon dioxide on soil carbon: a comparison of four meta-analyses

Soil is the largest reservoir of organic carbon (C) in the terrestrial biosphere and soil C has a relatively long mean residence time. Rising atmospheric carbon dioxide (CO₂) concentrations generally increase plant growth and C input to soil, suggesting that soil might help mitigate atmospheric CO₂ rise and global warming. But to what extent mitigation will occur is unclear. The large size of the soil C pool not only makes it a potential buffer against rising atmospheric CO₂, but also makes it difficult to measure changes amid the existing background. Meta‐analysis is one tool that can overcome the limited power of single studies. Four recent meta‐analyses addressed this issue but reached somewhat different conclusions about the effect of elevated CO₂ on soil C accumulation, especially regarding the role of nitrogen (N) inputs. Here, we assess the extent of differences between these conclusions and propose a new analysis of the data. The four meta‐analyses included different studies, derived different effect size estimates from common studies, used different weighting functions and metrics of effect size, and used different approaches to address nonindependence of effect sizes. Although all factors influenced the mean effect size estimates and subsequent inferences, the approach to independence had the largest influence. We recommend that meta‐analysts critically assess and report choices about effect size metrics and weighting functions, and criteria for study selection and independence. Such decisions need to be justified carefully because they affect the basis for inference. Our new analysis, with a combined data set, confirms that the effect of elevated CO₂ on net soil C accumulation increases with the addition of N fertilizers. Although the effect at low N inputs was not significant, statistical power to detect biogeochemically important effect sizes at low N is limited, even with meta‐analysis, suggesting the continued need for long‐term experiments.     

Who's your daddy? Paternity testing reveals promiscuity and multiple paternity in the carnivorous marsupial Dasyurus maculatus (Marsupialia: Dasyuridae)

Female promiscuity is common among mammals but its advantages, particularly for marsupials, remain unclear. Using microsatellite DNA from pouch young of known mothers, we identified the most likely fathers of 25 wild spotted-tailed quolls ( Dasyurus maculatus ) from six litters. We aimed to determine whether young within the same litter had different fathers, and whether breeding success of males was associated with large body mass (consistent with inter-male competition) or scrotal width (consistent with sperm competition). We also explored the possible influence of promiscuity on relatedness within litters. Finally, we used data on paternity and relatedness to make inferences regarding movement and dispersal.
Four litters were sired by more than one male, and three males sired offspring in more than one litter. Known fathers had higher body mass, but not scrotal width, than males of unknown paternity status, suggesting that males may compete for access to females. Sires were less related to dams than expected by chance, and litters with multiple paternity had lower relatedness than litters sired by a single male.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 1–7.