Angiogenin, a potent inducer of neovascularization, is the only angiogenic molecule known to exhibit ribonucleolytic activity. Its overall structure, as determined at 2.4 A, is similar to that of pancreatic ribonuclease A, but it differs markedly in several distinct areas, particularly the ribonucleolytic active center and the putative receptor binding site, both of which are critically involved in biological function. Most strikingly, the site that is spatially analogous to that for pyrimidine binding in ribonuclease A differs significantly in conformation and is "obstructed" by glutamine-117. Movement of this and adjacent residues may be required for substrate binding to angiogenin and, hence, constitute a key part of its mechanism of action.
Angiostrongylus vasorum is a highly pathogenic metastrongylid nematode affecting dogs, which uses gastropod molluscs as intermediate hosts. The geographical distribution of the parasite appears to be heterogeneous or patchy and understanding of the factors underlying this heterogeneity is limited. In this study, we compared the species of gastropod present and the prevalence of A. vasorum along a rural–urban gradient in two cities in the south-west United Kingdom. The study was conducted in Swansea in south Wales (a known endemic hotspot for A. vasorum) and Bristol in south-west England (where reported cases are rare). In each location, slugs were sampled from nine sites across three broad habitat types (urban, suburban and rural). A total of 180 slugs were collected in Swansea in autumn 2012 and 338 in Bristol in summer 2014. A 10 mg sample of foot tissue was tested for the presence of A. vasorum by amplification of the second internal transcribed spacer (ITS-2) using a previously validated real-time PCR assay. There was a significant difference in the prevalence of A. vasorum in slugs between cities: 29.4 % in Swansea and 0.3 % in Bristol. In Swansea, prevalence was higher in suburban than in rural and urban areas. Comparing the sampled slug fauna, Arion rufus was found in greater numbers in Swansea than Bristol, and was commonly infected (prevalence 41 %). This, alongside the timing of slug collections in summer rather than autumn, could explain low infection prevalence in the Bristol sample. In the absence of Ar. rufus as a preferred host for A. vasorum, Ar. flagellus and Limacus maculatus appear to act as versatile hosts that are present in suburban and urban areas in Swansea (prevalence in Ar. flagellus 33 %; in L. maculatus 44 %) and in Bristol (prevalence in Ar. flagellus 0.9 %). These slug species might provide A. vasorum with an alternative vehicle to reach the final host, when the main host Ar. rufus is scarce or absent. We conclude that the composition of the slug fauna varies spatially, and that this could help explain patchiness in the prevalence of A. vasorum. A suburban peak was found in the prevalence of infection in intermediate hosts, perhaps explained by a higher density of competent intermediate and/or definitive hosts.
The Western European Hedgehog (Erinaceous europaeus) is a nocturnal animal that is in decline in much of Europe, but the monitoring of this species is subjective, prone to error, and an inadequate basis for estimating population trends. Here, we report the use of Crenosoma striatum, a parasitic nematode specific to hedgehogs as definitive hosts, to detect hedgehog presence in the natural environment. This is achieved through collecting and sampling the parasites within their intermediate hosts, gastropoda, a group much simpler to locate and sample in both urban and rural habitats. C. striatum and Crenosoma vulpis were collected post-mortem from the lungs of hedgehogs and foxes, respectively. Slugs were collected in two sessions, during spring and autumn, from Skomer Island (n = 21), which is known to be free of hedgehogs (and foxes); and Pennard, Swansea (n = 42), known to have a healthy hedgehog population. The second internal transcribed spacer of parasite ribosomal DNA was used to develop a highly specific, novel, PCR based multiplex assay. Crenosoma striatum was found only at the site known to be inhabited by hedgehogs, at an average prevalence in gastropods of 10% in spring and autumn. The molecular test was highly specific: One mollusc was positive for both C. striatum and C. vulpis, and differentiation between the two nematode species was clear. This study demonstrates proof of principle for using detection of specific parasite DNA in easily sampled intermediate hosts to confirm the presence of an elusive nocturnal definitive host species. The approach has great potential as an adaptable, objective tool to supplement and support existing ecological survey methods.
Understanding how landscape connectivity affects gene flow can help to guide the management of animal species of conservation concern. One such species is the West European hedgehog (Erinaceus europaeus), which has seen significant declines across its distribution, with the highest rate of declines being reported in rural areas of the UK. The drivers of these declines are not well understood, but anthropogenic changes in the landscape such as modified agricultural practices and increased road traffic have been proposed to play a part. These impacts are likely to fragment populations into smaller sub‐populations, leading to genetic differentiation and depletion. Here, we used genetic (microsatellite) and landscape data to investigate the impact of habitat resistance and landscape features (roads and waterways) on the genetic structure of hedgehogs across a 5800 km2 area of South Wales, UK. We found evidence of weak genetic structuring, with four genetic clusters present across the study area, but many individuals were admixed. We found no evidence that this genetic structure was related to roads, waterways, habitat resistance, or geographic distance, suggesting that hedgehogs may be able to disperse across these potential barriers frequently enough to minimise genetic fragmentation. This study demonstrates the importance of understanding the interactions between a species and the wider landscape to inform conservation management.
WOWellcome Sanger Institute Scientific Operations: Sequencing Operations
Wellcome Sanger Institute Scientific Operations: Sequencing Operations
WTWellcome Sanger Institute Tree of Life Core Informatics team
Wellcome Sanger Institute Tree of Life Core Informatics team
TCTree of Life Core Informatics collective
Tree of Life Core Informatics collective
DCDarwin Tree of Life Consortium
Darwin Tree of Life Consortium
We present a genome assembly from an individual female Erinaceus europaeus (the western European hedgehog; Chordata; Mammalia; Eulipotyphla; Erinaceidae). The genome sequence spans 2,720.70 megabases. Most of the assembly is scaffolded into 24 chromosomal pseudomolecules, including the X sex chromosome. The mitochondrial genome has also been assembled and is 17.43 kilobases in length.