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Amongst newly developed approaches to analyse molecular data, phylodynamic models are receiving much attention because of their potential to reveal changes to viral populations over short periods. This knowledge can be very important for understanding disease impacts. However, their accuracy needs to be fully understood, especially in relation to wildlife disease epidemiology, where sampling and prior knowledge may be limited. The release of the rabbit haemorrhagic disease virus (RHDV) as biological control in naive rabbit populations in Australia in 1996 provides a unique dataset with which to validate phylodynamic models. By comparing the results obtained for RHDV1 with our current understanding of the RHDV epidemiology in Australia, we evaluated the performances of these recently developed models. In line with our expectations, coalescent analyses detected a sharp increase in the virus trajectory in the first few months after the virus release, followed by a more gradual increase. The phylodynamic analyses with a birth-death tree prior generated effective reproductive number estimates (the average number of secondary infections per each infectious case, Re) larger than one for most of the epochs considered. However, the possible range of the initial Re included estimates lower than one despite the known rapid spread of RHDV1 in Australia. Furthermore, the analyses that took into account the geographical structuring failed to converge. We argue that the difficulties that we encountered most likely stem from the fact that the samples available from 1996 to 2014 were too sparse with respect to geographic and within outbreak coverage to adequately infer some of the model parameters. In general, while these Bayesian analyses proved to be greatly informative in some regards, we caution that their interpretation may not be straight forward and recommend further research in evaluating the robustness of these models to assumption violations and sensitivity to sampling regimes.

BackgroundNumerous studies in veterinary species have recently linked vitamin D status with non-skeletal health disorders. Previous studies have indicated that dogs cannot produce endogenous vitamin D via cutaneous production and rely solely on dietary intake of vitamin D. The seasonal variation of vitamin D seen in humans due to changes in UV exposure therefore is unlikely to be replicated in these animals.ObjectivesThe objective of this study was to investigate the natural variation in 25-hydroxyvitamin-D concentration in dogs subject to seasonal UV exposure.MethodsThis longitudinal study followed 18 healthy dogs fed a standardized diet over one year, with blood samples obtained monthly. Two key vitamin D metabolites, 25-hydroxyvitamin-D2 and 25-hydroxyvitamin-D3, were assessed by liquid chromatography tandem mass spectrometry in serum samples. Various other biochemical parameters were also measured. Seasonality was assessed using Cosinor statistical analysis.ResultsAlthough the dogs were subject to seasonally varying UV radiation, 25-hydroxyvitamin-D and related biomarkers (including calcium and parathyroid hormone) remained stable over time and did not follow a seasonal pattern. 25-hydroxyvitamin-D was not positively correlated to exposure to UV radiation. Nonetheless, variation in 25-hydroxyvitamin-D concentration between individual dogs was detected.ConclusionsGiven the standardization of diet, we concluded that the seasonal stability of 25-hydroxyvitamin-D concentration (vitamin D status) was likely a direct result of lack of cutaneous vitamin D production in this species and highlights the importance of dietary intake. The variation in 25-hydroxyvitamin-D concentration between animals warrants further investigatio

Multi-strain, host-disease dynamics describe a system where multiple strains of a pathogen compete for susceptible individuals of a single host. The theoretical properties of these systems have been well studied, but there are few empirical studies in wildlife hosts. We examined the impacts of two novel strains of rabbit haemorrhagic disease virus (RHDV) recently introduced into Australia, one inadvertently (RHDV2) and one deliberately for rabbit biocontrol (RHDV-K5), by analysing long-term monitoring data for introduced European rabbits (Oryctolagus cuniculus) from 18 sites throughout Australia. We examined population-level impacts using rabbit spotlight counts pre- and post-arrival of the two strains. We also analysed serological data to determine potential interactions among the introduced and existing field strains of RHDV, as well as a pre-existing benign strain of calicivirus (RCV-A1). Serological analyses suggested that RHDV2 arrived in Australia during spring 2014 and spread rapidly through the Australian rabbit population within two years. Following the establishment of RHDV2, rabbit abundance was reduced by an average of 60%, with impacts most pronounced in southern and western Australia. In contrast, the deliberate release of RHDV-K5 had little impact on rabbit populations. Although RHDV2 has spread rapidly throughout Australia, our serological analyses do not support the observation that RHDV2 is rapidly replacing existing field strains of RHDV, as was previously reported in Australia and Europe. Nevertheless, RHDV2 has negatively impacted the ability of RHDV and RCV-A1 to spread within rabbit populations, most likely due to its ability to infect juvenile rabbits, thereby removing them from the pool of susceptible individuals available to be infected by competing strains. Synthesis and applications. The impact of the release of a novel strain of rabbit haemorrhagic disease virus (RHDV-K5) for rabbit biocontrol in Australia has been suppressed by the emergence of a competing strain, RHDV2. Hence, the success of further releases of similar RHDV strains for rabbit biocontrol appear doubtful. Despite this, RHDV2 has suppressed rabbit abundances by an average of 60%, with impacts most pronounced in southern and western Australia. Whether the incursion of RHDV2 leads to the competitive exclusion of other endemic RHDV strains remains to be resolved. However, the existence of partial cross-immunity could allow some level of coexistence between RHDV2 and RHDV strains, at least in the medium term.

Retinal detachment is a serious and common condition, but genetic studies to date have been hampered by the small size of the assembled cohorts. In the UK Biobank dataset, where retinal detachment was ascertained by self-report or hospital records, genetic correlations between retinal detachment and high myopia or cataract operation were respectively 0.46 (SE=0.08) and 0.44 (SE=0.07). These correlations are consistent with known epidemiological associations. Through meta-analysis of genome-wide association studies using UK Biobank retinal detachment cases (N=3977) and two cohorts, each comprising ~1000 clinically-ascertained rhegmatogenous retinal detachment patients, we uncovered 11 genome-wide significant association signals. These are near or within ZC3H11B, BMP3, COL22A1, DLG5, PLCE1, EFEMP2, TYR, FAT3, TRIM29, COL2A1 and LOXL1. Replication in the 23andMe dataset, where retinal detachment is self-reported by participants, firmly establishes six retinal detachment risk loci: FAT3, COL22A1, TYR, BMP3, ZC3H11B and PLCE1. Based on the genetic associations with eye traits described to date, the first two specifically impact risk of a retinal detachment, while the last four point to shared aetiologies with macular condition, myopia and glaucoma. Fine-mapping prioritised the lead common missense variant (TYR S192Y) as causal variant at the TYR locus and a small set of credible causal variants at the FAT3 locus. The larger study size presented here, enabled by resources linked to health records or self-report, provides novel insights into retinal detachment aetiology and underlying pathological pathways.

A growing body of evidence indicates a potential role for the gut-brain axis as a novel therapeutic target in treating seizures. The present study sought to characterize the gut microbiome in Theiler murine encephalomyelitis virus (TMEV)-induced seizures, and to evaluate the effect of microbial metabolite S-equol on neuronal physiology as well as TMEV-induced neuronal hyperexcitability ex vivo.We infected C57BL/6J mice with TMEV and monitored the development of acute behavioral seizures 0-7 days postinfection (dpi). Fecal samples were collected at 5-7 dpi and processed for 16S sequencing, and bioinformatics were performed with QIIME2. Finally, we conducted whole-cell patch-clamp recordings in cortical neurons to investigate the effect of exogenous S-equol on cell intrinsic properties and neuronal hyperexcitability.We demonstrated that gut microbiota diversity is significantly altered in TMEV-infected mice at 5-7 dpi, exhibiting separation in beta diversity in TMEV-infected mice dependent on seizure phenotype, and lower abundance of genus Allobaculum in TMEV-infected mice regardless of seizure phenotype. In contrast, we identified specific loss of S-equol-producing genus Adlercreutzia as a microbial hallmark of seizure phenotype following TMEV infection. Electrophysiological recordings indicated that exogenous S-equol alters cortical neuronal physiology. We found that entorhinal cortex neurons are hyperexcitable in TMEV-infected mice, and exogenous application of microbial-derived S-equol ameliorated this TMEV-induced hyperexcitability.Our study presents the first evidence of microbial-derived metabolite S-equol as a potential mechanism for alteration of TMEV-induced neuronal excitability. These findings provide new insight for the novel role of S-equol and the gut-brain axis in epilepsy treatment.

The increasing popularity of citizen science in ecological research has created opportunities for data collection from large teams of observers that are widely dispersed. We established a citizen science program to complement the release of a new variant of the rabbit biological control agent, rabbit haemorrhagic disease virus (RHDV), known colloquially as K5, across Australia. We evaluated the impact of K5 on the national rabbit population and compared citizen science and professionally-collected spotlight count data. Of the citizen science sites (n = 219), 93% indicated a decrease in rabbit abundance following the release of K5. The overall finite monthly growth rate in rabbit abundance was estimated as 0.66 (95%CI, 0.26, 1.03), averaging a monthly reduction of 34% at the citizen science sites one month after the release. No such declines were observed at the professionally monitored sites (n = 22). The citizen science data submissions may have been unconsciously biased or the number of professional sites may have been insufficient to detect a change. Citizen science participation also declined by 56% over the post-release period. Future programs should ensure the use of blinded trials to check for unconscious bias and consider how incentives and/or the good will of the participants can be maintained throughout the program.

The original version of this Article contained an error in Fig. 2, in which panels a and b were inadvertently swapped. This has now been corrected in the PDF and HTML versions of the Article.

The European rabbit (Oryctolagus cuniculus) is a notorious economic and environmental pest species in its invasive range. To better understand the population and range dynamics of this species, 41 yr of abundance data have been collected from 116 unique sites across a broad range of climatic and environmental conditions in Australia. We analyzed this time series of abundance data to determine whether interannual variation in climatic conditions can be used to map historic, contemporary, and potential future fluctuations in rabbit abundance from regional to continental scales. We constructed a hierarchical Bayesian regression model of relative abundance that corrected for observation error and seasonal biases. The corrected abundances were regressed against environmental and disease variables in order to project high spatiotemporal resolution, continent-wide rabbit abundances. We show that rabbit abundance in Australia is highly variable in space and time, being driven primarily by internnual variation in temperature and precipitation in concert with the prevalence of a non-pathogenic virus. Moreover, we show that internnual variation in local spatial abundances can be mapped effectively at a continental scale using highly resolved spatiotemporal predictors, allowing "hot spots" of persistently high rabbit abundance to be identified. Importantly, cross-validated model performance was fair to excellent within and across distinct climate zones. Long-term monitoring data for invasive species can be used to map fine-scale spatiotemporal fluctuations in abundance patterns when accurately accounting for inherent sampling biases. Our analysis provides ecologists and pest managers with a clearer understanding of the determinants of rabbit abundance in Australia, offering an important new approach for predicting spatial abundance patterns of invasive species at the near-term temporal scales that are directly relevant to resource management.

Background: PDE4 cyclic nucleotide phosphodiesterases regulate 3′, 5′ cAMP abundance in the CNS and thereby regulate PKA activity and phosphorylation of CREB, which has been implicated in learning and memory, depression and other functions. The PDE4 isoform PDE4B1 also interacts with the DISC1 protein, implicated in neural development and behavioral disorders. The cellular functions of PDE4B1 have been investigated extensively, but its function(s) in the intact organism remained unexplored. Results: To specifically disrupt PDE4B1, we developed mice that express a PDE4B1-D564A transgene in the hippocampus and forebrain. The transgenic mice showed enhanced phosphorylation of CREB and ERK1/2 in hippocampus. Hippocampal neurogenesis was increased in the transgenic mice. Hippocampal electrophysiological studies showed increased baseline synaptic transmission and enhanced LTP in male transgenic mice. Behaviorally, male transgenic mice showed increased activity in prolonged open field testing, but neither male nor female transgenic mice showed detectable anxiety-like behavior or antidepressant effects in the elevated plus-maze, tail-suspension or forced-swim tests. Neither sex showed any significant differences in associative fear conditioning or showed any demonstrable abnormalities in pre-pulse inhibition. Conclusions: These data support the use of an isoform-selective approach to the study of PDE4B1 function in the CNS and suggest a probable role of PDE4B1 in synaptic plasticity and behavior. They also provide additional rationale and a refined approach to the development of small-molecule PDE4B1-selective inhibitors, which have potential functions in disorders of cognition, memory, mood and affect. The McKnight Foundation (no grant number, for research support and also funding of the behavioral and electrophysiology cores), the Bolger Prostate Cancer Research Fund (no grant number), and the National Cancer Institute of the National Institutes of Health to the University of Alabama at Birmingham Comprehensive Cancer Center under award number P30 CA013148 (for generation of transgenic mice and DNA sequencing). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or the McKnight Foundation, neither of which played any role on the in study design; in the collection, analysis, and interpretation of data; in the writing of the manuscript; or in the decision to submit the manuscript for publication. Published version

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder that is predominantly caused by alterations of the methyl-CpG-binding protein 2 (MECP2) gene. Disease severity and the presence of comorbidities such as gastrointestinal distress vary widely across affected individuals. The gut microbiome has been implicated in neurodevelopmental disorders such as Autism Spectrum Disorder (ASD) as a regulator of disease severity and gastrointestinal comorbidities. Although the gut microbiome has been previously characterized in humans with RTT compared to healthy controls, the impact of MECP2 mutation on the composition of the gut microbiome in animal models where the host and diet can be experimentally controlled remains to be elucidated. By evaluating the microbial community across postnatal development as behavioral symptoms appear and progress, we have identified microbial taxa that are differentially abundant across developmental timepoints in a zinc-finger nuclease rat model of RTT compared to WT. We have additionally identified p105 as a key translational timepoint. Lastly, we have demonstrated that fecal SCFA levels are not altered in RTT rats compared to WT rats across development. Overall, these results represent an important step in translational RTT research.

International audience; With ongoing introductions into Australia since the 1700s, the European rabbit (Oryctolagus cuniculus) has become one of the most widely distributed and abundant vertebrate pests, adversely impacting Australia's biodiversity and agroeconomy. To understand the population and range dynamics of the species and its impacts better, occurrence and abundance data have been collected by researchers and citizens from sites covering a broad spectrum of climatic and environmental conditions in Australia. The lack of a common and accessible repository for these data has, however, limited their use in determining important spatiotemporal drivers of the structure and dynamics of the geographical range of rabbits in Australia. To meet this need, we created the Australian National Rabbit Database, which combines more than 50 yr of historical and contemporary survey data collected from throughout the range of the species in Australia. The survey data, obtained from a suite of complementary monitoring methods, were combined with high‐resolution weather, climate, and environmental information, and an assessment of data quality. The database provides records of rabbit occurrence (689,265 records) and abundance (51,241 records, >120 distinct sites) suitable for identifying the spatiotemporal drivers of the rabbit's distribution and for determining spatial patterns of variation in its key life‐history traits, including maximum rates of population growth. Because all data are georeferenced and date stamped, they can be coupled with information from other databases and spatial layers to explore the potential effects of rabbit occurrence and abundance on Australia's native wildlife and agricultural production. The Australian National Rabbit Database is an important tool for understanding and managing the European rabbit in its invasive range and its effects on native biodiversity and agricultural production. It also provides a valuable resource for addressing questions related to the biology, success, and impacts of invasive species more generally. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

Rabbit hemorrhagic disease virus 2 (RHDV2; Lagovirus GI.2) is a pathogenic calicivirus that affects European rabbits ( Oryctolagus cuniculus ) and various hare ( Lepus ) species. GI.2 was first detected in France in 2010 and subsequently caused epidemics in wild and domestic lagomorph populations throughout Europe. In May 2015, GI.2 was detected in Australia. Within 18 months of its initial detection, GI.2 had spread to all Australian states and territories and rapidly became the dominant circulating strain, replacing Rabbit hemorrhagic disease virus (RHDV/GI.1) in mainland Australia. Reconstruction of the evolutionary history of 127 Australian GI.2 isolates revealed that the virus arrived in Australia at least several months before its initial description and likely circulated unnoticed in wild rabbit populations in the east of the continent prior to its detection. GI.2 sequences isolated from five hares clustered with sequences from sympatric rabbit populations sampled contemporaneously, indicating multiple spillover events into hares rather than an adaptation of the Australian GI.2 to a new host. Since the presence of GI.2 in Australia may have wide-ranging consequences for rabbit biocontrol, particularly with the release of the novel biocontrol agent GI.1a/RHDVa-K5 in March 2017, ongoing surveillance is critical to understanding the interactions of the various lagoviruses in Australia and their impact on host populations. IMPORTANCE This study describes the spread and distribution of Rabbit hemorrhagic disease virus 2 (GI.2) in Australia since its first detection in May 2015. Within the first 18 months following its detection, RHDV2 spread from east to west across the continent and became the dominant strain in all mainland states of Australia. This has important implications for pest animal management and for owners of pet and farmed rabbits, as there currently is no effective vaccine available in Australia for GI.2. The closely related RHDV (GI.1) is used to control overabundant wild rabbits, a serious environmental and agricultural pest in this country, and it is currently unclear how the widespread circulation of GI.2 will impact ongoing targeted wild rabbit management operations.

The Gut Microbiota Mediates the Anti-Seizure Effects of the Ketogenic Diet.Olson CA, Vuong HE, Yano JM, Liang QY, Nusbaum DJ, Hsiao EY Cell 2018;173:P1728–P1741.e13.The ketogenic diet (KD) is used ...

The common starling (Sturnus vulgaris) has a proven invasion history in many countries, and at a continental scale in North America and Australasia. In Australia, starlings are firmly established throughout the eastern states and Tasmania. Incursions of starlings into Western Australia (WA) represent a significant threat to this State’s agricultural, public amenity and biodiversity assets. We present models of starling population dynamics that incorporate environmental and control effort variability. We incorporate knowledge of starling ecology with economic data to assess the potential economic cost of starlings establishing in WA, evaluating the cost–benefits for each management scenario. We calculated starling population size will approach carrying capacity in WA within as little as 30 years if left unchecked. A population of this size could cost the WA economy up to $43.7 million annually in 2011/2012 dollars. Over a 50 year horizon, the conservative benefit–cost ratio for ongoing detection and control at the current level of expenditure is 6.03:1. However, even under current levels of control, starling numbers are projected to increase to almost 11 million by 2061. Further improvements in the efficiency of starling detection and control and/or an increased level of expenditure on detection and control are required.

Seizures frequently accompany gliomas and often escalate to peritumoral epilepsy. Previous work revealed the importance of tumor-derived excitatory glutamate (Glu) release mediated by the cystine-glutamate transporter (SXC) in epileptogenesis. We now show a novel contribution of GABAergic disinhibition to disease pathophysiology. In a validated mouse glioma model, we found that peritumoral parvalbumin-positive GABAergic inhibitory interneurons are significantly reduced, corresponding with deficits in spontaneous and evoked inhibitory neurotransmission. Most remaining peritumoral neurons exhibit elevated intracellular Cl(-) concentration ([Cl(-) ]i ) and consequently depolarizing, excitatory gamma-aminobutyric acid (GABA) responses. In these neurons, the plasmalemmal expression of KCC2, which establishes the low [Cl(-) ]i required for GABAA R-mediated inhibition, is significantly decreased. Interestingly, reductions in inhibition are independent of Glu release, but the presence of both decreased inhibition and decreased SXC expression is required for epileptogenesis. We suggest GABAergic disinhibition renders peritumoral neuronal networks hyper-excitable and susceptible to seizures triggered by excitatory stimuli, and propose KCC2 as a therapeutic target.

Forced vital capacity (FVC), a spirometric measure of pulmonary function, reflects lung volume and is used to diagnose and monitor lung diseases. We performed genome-wide association study meta-analysis of FVC in 52,253 individuals from 26 studies and followed up the top associations in 32,917 additional individuals of European ancestry. We found six new regions associated at genome-wide significance (P

Time to fall asleep (sleep latency) is a major determinant of sleep quality. Chronic, long sleep latency is a major characteristic of sleep-onset insomnia and/or delayed sleep phase syndrome. In this study we aimed to discover common polymorphisms that contribute to the genetics of sleep latency. We performed a meta-analysis of genome-wide association studies (GWAS) including 2 572 737 single nucleotide polymorphisms (SNPs) established in seven European cohorts including 4242 individuals. We found a cluster of three highly correlated variants (rs9900428, rs9907432 and rs7211029) in the RNA-binding protein fox-1 homolog 3 gene (RBFOX3) associated with sleep latency (P-values=5.77 × 10(-08), 6.59 × 10(-)(08) and 9.17 × 10(-)(08)). These SNPs were replicated in up to 12 independent populations including 30 377 individuals (P-values=1.5 × 10(-)(02), 7.0 × 10(-)(03) and 2.5 × 10(-)(03); combined meta-analysis P-values=5.5 × 10(-07), 5.4 × 10(-07) and 1.0 × 10(-07)). A functional prediction of RBFOX3 based on co-expression with other genes shows that this gene is predominantly expressed in brain (P-value=1.4 × 10(-316)) and the central nervous system (P-value=7.5 × 10(-)(321)). The predicted function of RBFOX3 based on co-expression analysis with other genes shows that this gene is significantly involved in the release cycle of neurotransmitters including gamma-aminobutyric acid and various monoamines (P-values

Biological invasions are not only a major threat to biodiversity, they also have major impacts on local economies and agricultural production systems. Once established, the connection of local populations into metapopulation networks facilitates dispersal at landscape scales, generating spatial dynamics that can impact the outcome of pest-management actions. Much planning goes into landscape-scale invasive species management. However, effective management requires knowledge on the interplay between metapopulation network topology and management actions. We address this knowledge gap using simulation models to explore the effectiveness of two common management strategies, applied across different extents and according to different rules for selecting target localities in metapopulations with different network topologies. These management actions are: (i) general population reduction, and (ii) reduction of an obligate resource. The reduction of an obligate resource was generally more efficient than population reduction for depleting populations at landscape scales. However, the way in which local populations are selected for management is important when the topology of the metapopulation is heterogeneous in terms of the distribution of connections among local populations. We tested these broad findings using real-world scenarios of European rabbits (Oryctolagus cuniculus) infesting agricultural landscapes in Western Australia. Although management strategies targeting central populations were more effective in simulated heterogeneous metapopulation structures, no difference was observed in real-world metapopulation structures that are highly homogeneous. In large metapopulations with high proximity and connectivity of neighbouring populations, different spatial management strategies yield similar outcomes. Directly considering spatial attributes in pest-management actions will be most important for metapopulation networks with heterogeneously distributed links. Our modelling framework provides a simple approach for identifying the best possible management strategy for invasive species based on metapopulation structure and control capacity. This information can be used by managers trying to devise efficient landscape-oriented management strategies for invasive species and can also generate insights for conservation purposes.

Invasive species represent the second greatest threat to biodiversity after habitat loss, and significantly affect agriculture worldwide. The Common Starling (Sturnus vulgaris) is one of the world’s worst invasive species and has established pest populations across the globe, with low-density, highly persecuted populations in Western Australia (WA) since the 1970s. This study examines the ongoing control of low-density populations of Common Starlings in WA. From May 2006 to June 2009 we monitored use by Common Starlings of 180 artificial nest-cavities of three designs, across three habitat types; the artificial cavities were standard wooden nest-boxes, and terracotta pipes orientated vertically or horizontally. During the trial, Common Starlings nested exclusively in wooden nest-boxes in swamps containing predominantly dead trees; they did not nest in the terracotta pipes. Wooden nest-boxes may have helped concentrate breeding Common Starlings in a defined area, thereby assisting control efforts.

Age-related macular degeneration (AMD) is a leading cause of visual loss in Western populations. Susceptibility is influenced by age, environmental and genetic factors. Known genetic risk loci do not account for all the heritability. We therefore carried out a genome-wide association study of AMD in the UK population with 893 cases of advanced AMD and 2199 controls. This showed an association with the well-established AMD risk loci ARMS2 (age-related maculopathy susceptibility 2)-HTRA1 (HtrA serine peptidase 1) (P =2.7 × 10(-72)), CFH (complement factor H) (P =2.3 × 10(-47)), C2 (complement component 2)-CFB (complement factor B) (P =5.2 × 10(-9)), C3 (complement component 3) (P =2.2 × 10(-3)) and CFI (P =3.6 × 10(-3)) and with more recently reported risk loci at VEGFA (P =1.2 × 10(-3)) and LIPC (hepatic lipase) (P =0.04). Using a replication sample of 1411 advanced AMD cases and 1431 examined controls, we confirmed a novel association between AMD and single-nucleotide polymorphisms on chromosome 6p21.3 at TNXB (tenascin XB)-FKBPL (FK506 binding protein like) [rs12153855/rs9391734; discovery P =4.3 × 10(-7), replication P =3.0 × 10(-4), combined P =1.3 × 10(-9), odds ratio (OR) = 1.4, 95% confidence interval (CI) = 1.3-1.6] and the neighbouring gene NOTCH4 (Notch 4) (rs2071277; discovery P =3.2 × 10(-8), replication P =3.8 × 10(-5), combined P =2.0 × 10(-11), OR = 1.3, 95% CI = 1.2-1.4). These associations remained significant in conditional analyses which included the adjacent C2-CFB locus. TNXB, FKBPL and NOTCH4 are all plausible AMD susceptibility genes, but further research will be needed to identify the causal variants and determine whether any of these genes are involved in the pathogenesis of AMD.

The Judas technique is a method used for landscape control of feral donkeys (Equus asinus) in northern Australia. Central to the success of any Judas program is the safe, efficient, and humane attachment of the telemetry device. For feral donkeys, this involves the use of field immobilization. We examine the replacement of the current chemical capture agent, succinylcholine, with contemporary immobilization agents to achieve positive animal welfare outcomes. A combination of medetomidine and ketamine delivered by remote injection from a helicopter was used to capture 14 free-ranging feral donkeys for the fitting of telemetry collars in Western Australia in November 2010. Dose rates of 0.14 mg/kg medetomidine and 4.1 mg/kg ketamine were appropriate to immobilize animals in 9 min (± SD = 3). Mean recovery time (total time in recumbency) was 21 min (± 14). All animals recovered uneventfully after being administered atipamezole, a specific antagonist of medetomidine, intramuscularly at 0.35 mg/kg. Physiologic parameters were recorded during recumbency, with environment-related hyperthermia being the only abnormality recognized. No significant complications were encountered, and this drug combination represents an efficient approach to capturing wild donkeys. This new method allows a rapid, safe, cost-effective approach to the immobilization of feral donkeys for use as Judas animals. This drug combination will replace the relatively inhumane succinylcholine for the field immobilization of feral donkeys.

We have used targeted genomic sequencing of high-complexity DNA pools based on long-range PCR and deep DNA sequencing by the SOLiD technology. The method was used for sequencing of 286 kb from four chromosomal regions with quantitative trait loci (QTL) influencing blood plasma lipid and uric acid levels in DNA pools of 500 individuals from each of five European populations. The method shows very good precision in estimating allele frequencies as compared with individual genotyping of SNPs (r(2) = 0.95, P < 10(-16)). Validation shows that the method is able to identify novel SNPs and estimate their frequency in high-complexity DNA pools. In our five populations, 17% of all SNPs and 61% of structural variants are not available in the public databases. A large fraction of the novel variants show a limited geographic distribution, with 62% of the novel SNPs and 59% of novel structural variants being detected in only one of the populations. The large number of population-specific novel SNPs underscores the need for comprehensive sequencing of local populations in order to identify the causal variants of human traits. European Journal of Human Genetics (2012) 20, 77-83; doi:10.1038/ejhg.2011.138; published online 3 August 2011

Epileptic seizures are a common and poorly understood comorbidity for individuals with primary brain tumors. To investigate peritumoral seizure etiology, we implanted human-derived glioma cells into severe combined immunodeficient mice. Within 14-18 d, glioma-bearing mice developed spontaneous and recurring abnormal electroencephalogram events consistent with progressive epileptic activity. Acute brain slices from these mice showed marked glutamate release from the tumor mediated by the system x(c)(-) cystine-glutamate transporter (encoded by Slc7a11). Biophysical and optical recordings showed glutamatergic epileptiform hyperexcitability that spread into adjacent brain tissue. We inhibited glutamate release from the tumor and the ensuing hyperexcitability by sulfasalazine (SAS), a US Food and Drug Administration-approved drug that blocks system x(c)(-). We found that acute administration of SAS at concentrations equivalent to those used to treat Crohn's disease in humans reduced epileptic event frequency in tumor-bearing mice compared with untreated controls. SAS should be considered as an adjuvant treatment to ameliorate peritumoral seizures associated with glioma in humans.

Background— Fibrin fragment D-dimer, one of several peptides produced when crosslinked fibrin is degraded by plasmin, is the most widely used clinical marker of activated blood coagulation. To identity genetic loci influencing D-dimer levels, we performed the first large-scale, genome-wide association search. Methods and Results— A genome-wide investigation of the genomic correlates of plasma D-dimer levels was conducted among 21 052 European-ancestry adults. Plasma levels of D-dimer were measured independently in each of 13 cohorts. Each study analyzed the association between ≈2.6 million genotyped and imputed variants across the 22 autosomal chromosomes and natural-log–transformed D-dimer levels using linear regression in additive genetic models adjusted for age and sex. Among all variants, 74 exceeded the genome-wide significance threshold and marked 3 regions. At 1p22, rs12029080 ( P =6.4×10 −52 ) was 46.0 kb upstream from F3 , coagulation factor III (tissue factor). At 1q24, rs6687813 ( P =2.4×10 −14 ) was 79.7 kb downstream of F5 , coagulation factor V. At 4q32, rs13109457 ( P =2.9×10 −18 ) was located between 2 fibrinogen genes: 10.4 kb downstream from FGG and 3.0 kb upstream from FGA . Variants were associated with a 0.099-, 0.096-, and 0.061-unit difference, respectively, in natural-log–transformed D-dimer and together accounted for 1.8% of the total variance. When adjusted for nonsynonymous substitutions in F5 and FGA loci known to be associated with D-dimer levels, there was no evidence of an additional association at either locus. Conclusions— Three genes were associated with fibrin D-dimer levels. Of these 3, the F3 association was the strongest, and has not been previously reported.

Based on the observed inverse association between hyperuricemia and Parkinson’s disease (PD) risk, the natural antioxidant activity of uric acid has been suggested to play a protective role. SLC2A9 has been indicated as the most effective of all uric acid transporters, and SLC2A9 variants have been shown to influence circulating uric acid levels. With this study, we aimed to test the association between such SLC2A9 polymorphisms and age at onset (AAO) of PD. Variants rs733175, rs737267, rs1014290, and rs6449213 within SLC2A9 were genotyped in 664 PD individuals from three European centers. The effect of each polymorphism on AAO was estimated within each center using a linear regression model adjusted for gender and genotype at the other SNPs and assuming an additive genetic model. Results across centers were combined using inverse-variance weighted fixed-effect meta-analysis. The minor allele of rs1014290, previously shown to be associated with lower serum uric acid levels, was found to be associated with a lower AAO of PD (pooled estimate −4.56 years; 95% CI −8.13, −1.00; p = 0.012). The association remained significant after adjustment for multiple comparisons and was highly consistent across centers (heterogeneity, I 2 0%). No gender differences were observed. Our study suggests that SLC2A9 genetic variants influence age of onset of Parkinson’s disease.

The thermal environment of day roosts is considered one of the most influential factors affecting the survival, growth and reproduction of microbats. The use of torpor is a common energy saving strategy employed by microbats in temperate regions. The efficiency of entry into, and arousal from, torpor is governed by roost microclimate, primarily roost temperature. The large-footed myotis Myotis macropus roosts in both tree cavities and a man-made tunnel at Yan Yean reservoir in Victoria, Australia. We investigated the thermal properties of both roost types in comparison to available tree cavities and ambient temperature over four time periods from October 2003 to May 2005. Tree cavities and tunnel roosts remained significantly warmer at night, cooler during the day, and were more stable than ambient temperatures. In addition, roost tree cavities were significantly cooler between 10:00–13:00 h compared to available tree cavities, and there was a trend for roost tree cavities to be slightly warmer at night a...

As major risk-factors for diabetes and cardiovascular diseases, the genetic contribution to obesity-related traits has been of interest for decades. Recently, a limited number of common genetic variants, which have replicated in different populations, have been identified. One approach to increase the statistical power in genetic mapping studies is to focus on populations with increased levels of linkage disequilibrium (LD) and reduced genetic diversity. We have performed joint linkage and genome-wide association analyses for weight and BMI in 3,448 (linkage) and 3,925 (association) partly overlapping healthy individuals from five European populations. A total of four chromosomal regions (two for weight and two for BMI) showed suggestive linkage (lod > 2.69) either in one of the populations or in the joint data. At the genome-wide level (nominal P < 1.6 x 10(-7), Bonferroni-adjusted P < 0.05) one single-nucleotide polymorphism (SNP) (rs12517906) (nominal P = 7.3 x 10(-8)) was associated with weight, whereas none with BMI. The SNP associated with weight is located close to MGAT1. The monoacylglycerol acyltransferase (MGAT) enzyme family is known to be involved in dietary fat absorption. There was no overlap between the linkage regions and the associated SNPs. Our results show that genetic effects influencing weight and BMI are shared across diverse European populations, even though some of these populations have experienced recent population bottlenecks and/or been affected by genetic drift. The analysis enabled us to identify a new candidate gene, MGAT1, associated with weight in women.

Invasive animals have been linked to the extinctions of native wildlife, and to significant agricultural financial losses or impacts. Current approaches to control invasive species require ongoing resources and management over large geographic scales, and often result in the short-term suppression of populations. New and innovative approaches are warranted. Recently, the RNA guided gene drive system based on CRISPR/Cas9 is being proposed as a potential gene editing tool that could be used by wildlife managers as a non-lethal addition or alternative to help reduce pest animal populations. While regulatory control and social acceptance are crucial issues that must be addressed, there is an opportunity now to identify the knowledge and research gaps that exist for some important invasive species. Here we systematically determine the knowledge gaps for pest species for which gene drives could potentially be applied. We apply a conceptual ecological risk framework within the gene drive context within an Australian environment to identify key requirements for undertaking work on seven exemplar invasive species in Australia. This framework allows an evaluation of the potential research on an invasive species of interest and within a gene drive and risk context. We consider the currently available biological, genetic and ecological information for the house mouse, European red fox, feral cat, European rabbit, cane toad, black rat and European starling to evaluate knowledge gaps and identify candidate species for future research. We discuss these findings in the context of future thematic areas of research worth pursuing in preparation for a more formal assessment of the use of gene drives as a novel strategy for the control of these and other invasive species. Keywords: Invasive species, Gene drive, CRISPR, Pest management, Islands

Smoking is a leading global cause of disease and mortality(1). We established the Oxford-GlaxoSmithKline study (Ox-GSK) to perform a genome-wide meta-analysis of SNP association with smoking-related behavioral traits. Our final data set included 41,150 individuals drawn from 20 disease, population and control cohorts. Our analysis confirmed an effect on smoking quantity at a locus on 15q25 (P = 9.45 x 10(-19)) that includes CHRNA5, CHRNA3 and CHRNB4, three genes encoding neuronal nicotinic acetylcholine receptor subunits. We used data from the 1000 Genomes project to investigate the region using imputation, which allowed for analysis of virtually all common SNPs in the region and offered a fivefold increase in marker density over HapMap2 (ref. 2) as an imputation reference panel. Our fine-mapping approach identified a SNP showing the highest significance, rs55853698, located within the promoter region of CHRNA5. Conditional analysis also identified a secondary locus (rs6495308) in CHRNA3.

Specialist species face higher extinction risks as a result of smaller, isolated populations with reduced gene flow. The large-footed myotis ( Myotis macropus ) is the only microbat in Australia specialised for foraging directly over water surfaces. Such highly specialised feeding ecology restricts the distribution of M. macropus to coastal regions and inland waterways. Using five novel and two existing nuclear microsatellite markers, we investigated genetic diversity within and among five M. macropus populations in Victoria. Significant genetic differentiation was detected between all populations. F ST values between populations ranged from 0.02 to 0.24. We suggest that the movement of M. macropus throughout the landscape is constrained by the availability of permanent waterways and associated riparian habitats. These findings represent important considerations for the conservation of this specialist species and the management of riparian vegetation, particularly on private land.

Glutamate transporters function to maintain low levels of extracellular glutamate and play an important role in synaptic transmission at many synapses. Disruption of glutamate transporter function or expression can result in increased extracellular glutamate levels. Alterations in glutamate transporter expression have been reported in human epilepsy and animal seizure models. Functional electrophysiological changes that occur when transporter expression is disrupted in chronic epilepsy models have not been examined. Here, we used a freeze-induced model of cortical dysplasia to test the role of glutamate transporters in synaptic hyperexcitability. We report that inhibiting glutamate transporters with the non-selective antagonist, DL-threo-beta-benzylozyaspartic acid (TBOA) preferentially prolongs postsynaptic currents (PSCs) and decreases the threshold for evoking epileptiform activity in lesioned compared to control cortex. The effect of inhibiting uptake is mediated primarily by the glia glutamate transporter (GLT-1) since the selective antagonist dihydrokainate (DHK) mimicked the effects of TBOA. The effect of uptake inhibition is mediated by activation of N-methyl-D-aspartate (NMDA) receptors since D-(-)-2-amino-5-phosphonovaleric acid (APV) prevents TBOA-induced effects. Neurons in lesioned cortex also have a larger tonic NMDA current. These results indicate that chronic changes in glutamate transporters and NMDA receptors contribute to hyperexcitability in cortical dysplasia.

A clear understanding is developing concerning the importance of epigenetic-related molecular mechanisms in transcription-dependent long-term memory formation. Chromatin modification, in particular histone acetylation, is associated with transcriptional activation, and acetylation of histone 3 (H3) occurs in Area CA1 of the hippocampus following contextual fear conditioning training. Conversely, DNA methylation is associated with transcriptional repression, but is also dynamically regulated in Area CA1 following training. We recently reported that inhibition of the enzyme responsible for DNA methylation, DNA methyltransferase (DNMT), in the adult rat hippocampus blocks behavioral memory formation. Here, we report that DNMT inhibition also blocks the concomitant memory-associated H3 acetylation, without affecting phosphorylation of its upstream regulator, extracellular signal-regulated kinase (ERK). Interestingly, the DNMT inhibitor-induced deficit in memory consolidation, along with deficits in long-term potentiation, can be rescued by pharmacologically increasing levels of histone acetylation prior to DNMT inhibition. These observations suggest that DNMT activity is not only necessary for memory and plasticity, but that DNA methylation may work in concert with histone modifications to regulate plasticity and memory formation in the adult rat hippocampus.

Uric acid is the end product of purine metabolism in humans and great apes, which have lost hepatic uricase activity, leading to uniquely high serum uric acid concentrations (200-500 microM) compared with other mammals (3-120 microM). About 70% of daily urate disposal occurs via the kidneys, and in 5-25% of the human population, impaired renal excretion leads to hyperuricemia. About 10% of people with hyperuricemia develop gout, an inflammatory arthritis that results from deposition of monosodium urate crystals in the joint. We have identified genetic variants within a transporter gene, SLC2A9, that explain 1.7-5.3% of the variance in serum uric acid concentrations, following a genome-wide association scan in a Croatian population sample. SLC2A9 variants were also associated with low fractional excretion of uric acid and/or gout in UK, Croatian and German population samples. SLC2A9 is a known fructose transporter, and we now show that it has strong uric acid transport activity in Xenopus laevis oocytes.

Glioma is the most common malignant primary brain tumor. Its rapid growth is aided by tumor-mediated glutamate release, creating peritumoral excitotoxic cell death and vacating space for tumor expansion. Glioma glutamate release may also be responsible for seizures, which complicate the clinical course for many patients and are often the presenting symptom. A hypothesized glutamate release pathway is the cystine/glutamate transporter System xc (-) (SXC), responsible for the cellular synthesis of glutathione (GSH). However, the relationship of SXC-mediated glutamate release, seizures, and tumor growth remains unclear. Probing expression of SLC7A11/xCT, the catalytic subunit of SXC, in patient and mouse-propagated tissues, we found that ~50% of patient tumors have elevated SLC7A11 expression. Compared with tumors lacking this transporter, in vivo propagated and intracranially implanted SLC7A11-expressing tumors grew faster, produced pronounced peritumoral glutamate excitotoxicity, induced seizures, and shortened overall survival. In agreement with animal data, increased SLC7A11 expression predicted shorter patient survival according to genomic data in the REMBRANDT (National Institutes of Health Repository for Molecular Brain Neoplasia Data) database. In a clinical pilot study, we used magnetic resonance spectroscopy to determine SXC-mediated glutamate release by measuring acute changes in glutamate after administration of the U.S. Food and Drug Administration-approved SXC inhibitor, sulfasalazine (SAS). In nine glioma patients with biopsy-confirmed SXC expression, we found that expression positively correlates with glutamate release, which is acutely inhibited with oral SAS. These data suggest that SXC is the major pathway for glutamate release from gliomas and that SLC7A11 expression predicts accelerated growth and tumor-associated seizures.

DYT1 dystonia is an inherited movement disorder caused by mutations in DYT1 (TOR1A), which codes for torsinA. Most of the patients have a trinucleotide deletion (ΔGAG) corresponding to a glutamic acid in the C-terminal region (torsinAΔE). Dyt1 ΔGAG heterozygous knock-in (KI) mice, which mimic ΔGAG mutation in the endogenous gene, exhibit motor deficits and deceased frequency of spontaneous excitatory post-synaptic currents (sEPSCs) and normal theta-burst-induced long-term potentiation (LTP) in the hippocampal CA1 region. Although Dyt1 KI mice show decreased hippocampal torsinA levels, it is not clear whether the decreased torsinA level itself affects the synaptic plasticity or torsinAΔE does it. To analyze the effect of partial torsinA loss on motor behaviors and synaptic transmission, Dyt1 heterozygous knock-out (KO) mice were examined as a model of a frame-shift DYT1 mutation in patients. Consistent with Dyt1 KI mice, Dyt1 heterozygous KO mice showed motor deficits in the beam-walking test. Dyt1 heterozygous KO mice showed decreased hippocampal torsinA levels lower than those in Dyt1 KI mice. Reduced sEPSCs and normal miniature excitatory post-synaptic currents (mEPSCs) were also observed in the acute hippocampal brain slices from Dyt1 heterozygous KO mice, suggesting that the partial loss of torsinA function in Dyt1 KI mice causes action potential-dependent neurotransmitter release deficits. On the other hand, Dyt1 heterozygous KO mice showed enhanced hippocampal LTP, normal inputoutput relations and paired pulse ratios in the extracellular field recordings. The results suggest that maintaining an appropriate torsinA level is important to sustain normal motor performance, synaptic transmission and plasticity. Developing therapeutics to restore a normal torsinA level may help to prevent and treat the symptoms in DYT1 dystonia. This work was supported by Tyler’s Hope for a Dystonia Cure, Inc., National Institutes of Health grants (NS37409, NS47466, NS47692, NS54246, NS57098, NS65273, NS72872, NS 74423, and NS82244), Howard Hughes Med-Grad Graduate Fellowship (CCC), and startup funds from the Lucille P. Markey Charitable Trust (UIUC) and Department of Neurology (UAB and UF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Epilepsy is one of the most common chronic neurologic diseases, yet approximately one-third of affected patients do not respond to anticonvulsive drugs that target neurons or neuronal circuits. Reactive astrocytes are commonly found in putative epileptic foci and have been hypothesized to be disease contributors because they lose essential homeostatic capabilities. However, since brain pathology induces astrocytes to become reactive, it is difficult to distinguish whether astrogliosis is a cause or a consequence of epileptogenesis. We now present a mouse model of genetically induced, widespread chronic astrogliosis after conditional deletion of β1-integrin (Itgβ1). In these mice, astrogliosis occurs in the absence of other pathologies and without BBB breach or significant inflammation. Electroencephalography with simultaneous video recording revealed that these mice develop spontaneous seizures during the first six postnatal weeks of life and brain slices show neuronal hyperexcitability. This was not observed in mice with neuronal-targeted β1-integrin deletion, supporting the hypothesis that astrogliosis is sufficient to induce epileptic seizures. Whole-cell patch-clamp recordings from astrocytes further suggest that the heightened excitability was associated with impaired astrocytic glutamate uptake. Moreover, the relative expression of the cation-chloride cotransporters (CCC) NKCC1 (Slc12a2) and KCC2 (Slc12a5), which are responsible for establishing the neuronal Cl−gradient that governs GABAergic inhibition were altered and the NKCC1 inhibitor bumetanide eliminated seizures in a subgroup of mice. These data suggest that a shift in the relative expression of neuronal NKCC1 and KCC2, similar to that observed in immature neurons during development, may contribute to astrogliosis-associated seizures.

Cortical dysplasia is associated with intractable epilepsy and developmental delay in young children. Recent work with the rat freeze-induced focal cortical dysplasia (FCD) model has demonstrated that hyperexcitability in the dysplastic cortex is due in part to higher levels of extracellular glutamate. Astrocyte glutamate transporters play a pivotal role in cortical maintaining extracellular glutamate concentrations. Here we examined the function of astrocytic glutamate transporters in a FCD model in rats. Neocortical freeze lesions were made in postnatal day (PN) 1 rat pups and whole cell electrophysiological recordings and biochemical studies were performed at PN 21–28. Synaptically evoked glutamate transporter currents in astrocytes showed a near 10-fold reduction in amplitude compared to sham operated controls. Astrocyte glutamate transporter currents from lesioned animals were also significantly reduced when challenged exogenously applied glutamate. Reduced astrocytic glutamate transport clearance contributed to increased NMDA receptor-mediated current decay kinetics in lesioned animals. The electrophysiological profile of astrocytes in the lesion group was also markedly changed compared to sham operated animals. Control astrocytes demonstrate large-amplitude linear leak currents in response to voltage-steps whereas astrocytes in lesioned animals demonstrated significantly smaller voltage-activated inward and outward currents. Significant decreases in astrocyte resting membrane potential and increases in input resistance were observed in lesioned animals. However, Western blotting, immunohistochemistry and quantitative PCR demonstrated no differences in the expression of the astrocytic glutamate transporter GLT-1 in lesioned animals relative to controls. These data suggest that, in the absence of changes in protein or mRNA expression levels, functional changes in astrocytic glutamate transporters contribute to neuronal hyperexcitability in the FCD model. National Institute of Mental Health NIMH: R01 NS075062 NIMH: NS090041 NIMH:P30-NS047466

Summary: Sodium-dependent high-affinity glutamate transporters regulate synaptic glutamate levels to maintain low ambient levels of glutamate and prevent excitotoxicity. Most studies using pharmacological inhibition of glutamate transport to examine the involvement of glutamate transporters in regulating synaptic activity have examined small synaptic currents. Using in vitro brain slices, we investigated the effects of uptake inhibition on two types of epileptiform activity, bicuculline-induced paroxysmal activity, and epileptiform responses in the freeze-lesion epilepsy model. In layer II/III pyramidal cells of the prefrontal cortex, inhibiting uptake with low concentrations of DL-threos-benzyloxyaspartic acid (TBOA) (20 or 30 µM) prolonged bicuculline-induced epileptiform activity. At higher concentrations, TBOA (150 or 300 µM) caused a transient enhancement of epileptiform discharges that was followed by a decrease. In the freeze-lesion model, inhibiting uptake also increased the amplitude and response area of evoked activity. The prolongation of epileptiform activity exhibited by the inhibition of glutamate uptake (TBOA 20 or 30 µM )i sattributed to an increase in the level of glutamate extracellularly during uptake blockade, resulting in sustained activation of glutamate receptors. The decrease in epileptiform activity at higher TBOA concentration could be due to glutamate receptor desensitization or loss of excitability due to a depolarization block. The present results suggest that decreases in glutamate uptake can be proconvulsant in the two models of epilepsy examined. Key Words: Glutamate uptake— Neocortex—TBOA—Cortical dysplasia—Epilepsy.

Islet amyloid polypeptide (IAPP) and insulin are expressed in the beta-cells of the islets of Langerhans. They are co-secreted in response to changes in glucose concentration, and their mRNA levels are also regulated by glucose. The promoters of both genes share similar cis-acting sequence elements, and both bind the homeodomain transcription factor PDX1, which plays an important role in the regulation of the insulin promoter and insulin mRNA levels by glucose. Here we examine the role of PDX1 in the regulation of the human IAPP promoter by glucose. The experiments were facilitated by the availability of a human beta-cell line (NES2Y) that lacks PDX1. NES2Y cells also lack operational K(ATP) channels, resulting in a loss of control of calcium signaling. We have previously used these cells to show that glucose regulation of the insulin gene is dependent on PDX1, but not calcium. In the mouse beta-cell line Min6, glucose (16 mm) stimulated a 3.5-4-fold increase in the activity of a -222 to +450 IAPP promoter construct compared with values observed in 0.5 mm glucose. In NES2Y cells, glucose failed to stimulate transcriptional activation of the IAPP promoter. Overexpression of PDX1 in NES2Y cells failed to reinstate glucose-responsive control of the IAPP promoter. Glucose effects on the IAPP promoter were observed only in the presence of PDX1 when normal calcium signaling was restored by overexpression of the two K(ATP) channel subunits SUR1 and Kir6.2. The importance of calcium was further emphasized by an experiment in which glucose-stimulated IAPP promoter activity was inhibited by the calcium channel blocker verapamil (50 microm). Verapamil was further shown to inhibit the stimulatory effect of glucose on IAPP mRNA levels. These results demonstrate that like the insulin promoter, glucose regulation of the IAPP promoter is dependent on the activity of PDX1, but unlike the insulin promoter, it additionally requires the activity of another, as yet uncharacterized factor(s), the activity of which is calcium-dependent.

Pax4 is a paired-box transcription factor that plays an important role in the development of pancreatic β-cells. Two Pax4 cDNAs were isolated from a rat insulinoma library. One contained the full-length sequence of Pax4. The other, termed Pax4c, was identical to Pax4 but lacked the sequences encoding 117 amino acids at the COOH-terminus. Pax4 was found to inhibit the human insulin promoter through a sequence element, the C2 box, located at −253 to −244, and the islet amyloid polypeptide promoter through a sequence element located downstream of −138. The inhibitory activity of Pax4 was mapped to separate regions of the protein between amino acids 2–230 and 231–349.

Elevated serum urate concentrations can cause gout, a prevalent and painful inflammatory arthritis. By combining data from >140,000 individuals of European ancestry within the Global Urate Genetics Consortium (GUGC), we identified and replicated 28 genome-wide significant loci in association with serum urate concentrations (18 new regions in or near TRIM46, INHBB, SFMBT1, TMEM171, VEGFA, BAZ1B, PRKAG2, STC1, HNF4G, A1CF, ATXN2, UBE2Q2, IGF1R, NFAT5, MAF, HLF, ACVR1B-ACVRL1 and B3GNT4). Associations for many of the loci were of similar magnitude in individuals of non-European ancestry. We further characterized these loci for associations with gout, transcript expression and the fractional excretion of urate. Network analyses implicate the inhibins-activins signaling pathways and glucose metabolism in systemic urate control. New candidate genes for serum urate concentration highlight the importance of metabolic control of urate production and excretion, which may have implications for the treatment and prevention of gout. © 2013 Nature America, Inc. All rights reserved.

Item does not contain fulltext Rhegmatogenous retinal detachment (RRD) is an important cause of vision loss and can potentially lead to blindness. The underlying pathogenesis is complex and incompletely understood. We applied a two-stage genetic association discovery phase followed by a replication phase in a combined total of 2833 RRD cases and 7871 controls. The discovery phase involved a genome-wide association scan of 867 affected individuals and 1953 controls from Scotland, followed by genotyping and testing 4347 highest ranking or candidate single nucleotide polymorphisms (SNPs) in independent sets of cases (1000) and controls (2912) of Dutch and British origin. None of the SNPs selected reached a Bonferroni-corrected threshold for significance (P < 1.27 x 10(-7)). The strongest association, for rs12960119 (P = 1.58 x 10(-7)) located within an intron of the SS18 gene. Further testing was carried out in independent case-control series from London (846 cases) and Croatia (120 cases). The combined meta-analysis identified one association reaching genome-wide significance for rs267738 (OR = 1.29, P = 2.11 x 10(-8)), a missense coding SNP and eQTL for CERS2 encoding the protein ceramide synthase 2. Several of the top signals showing suggestive significance in the combined meta-analysis encompassed genes with a documented role in cell adhesion or migration, including SS18, TIAM1, TSTA3 and LDB2, which warrant further investigation. This first genetic association study of RRD supports a polygenic component underlying RRD risk since 27.4% of the underlying RRD liability could be explained by the collective additive effects of the genotyped SNP from the discovery genome-wide scan.

Seuls les auteurs INRA et les 100 premiers auteurs figurent sur la notice. Group Authors : DIAbet Genetics Replication traits and provide insight into the underlying biological pathways La liste complète des auteurs et de leurs affiliations des auteurs est disponible sur la publication, p. 1004-1005, à l'adresse suivante : https://www.nature.com/articles/ng.2385.pdf; International audience; Through genome-wide association meta-analyses of up to 133,010 individuals of European ancestry without diabetes, including individuals newly genotyped using the Metabochip, we have increased the number of confirmed loci influencing glycemic traits to 53, of which 33 also increase type 2 diabetes risk (q < 0.05). Loci influencing fasting insulin concentration showed association with lipid levels and fat distribution, suggesting impact on insulin resistance. Gene-based analyses identified further biologically plausible loci, suggesting that additional loci beyond those reaching genome-wide significance are likely to represent real associations. This conclusion is supported by an excess of directionally consistent and nominally significant signals between discovery and follow-up studies. Functional analysis of these newly discovered loci will further improve our understanding of glycemic control.

Phospho- and sphingolipids are crucial cellular and intracellular compounds. These lipids are required for active transport, a number of enzymatic processes, membrane formation, and cell signalling. Disruption of their metabolism leads to several diseases, with diverse neurological, psychiatric, and metabolic consequences. A large number of phospholipid and sphingolipid species can be detected and measured in human plasma. We conducted a meta-analysis of five European family-based genome-wide association studies (N = 4034) on plasma levels of 24 sphingomyelins (SPM), 9 ceramides (CER), 57 phosphatidylcholines (PC), 20 lysophosphatidylcholines (LPC), 27 phosphatidylethanolamines (PE), and 16 PE-based plasmalogens (PLPE), as well as their proportions in each major class. This effort yielded 25 genome-wide significant loci for phospholipids (smallest P-value = 9.88×10−204) and 10 loci for sphingolipids (smallest P-value = 3.10×10−57). After a correction for multiple comparisons (P-value, Author Summary Phospho- and sphingolipids are integral to membrane formation and are involved in crucial cellular functions such as signalling, membrane fluidity, membrane protein trafficking, neurotransmission, and receptor trafficking. In addition to severe monogenic diseases resulting from defective phospho- and sphingolipid function and metabolism, the evidence suggests that variations in these lipid levels at the population level are involved in the determination of cardiovascular and neurologic traits and subsequent disease. We took advantage of modern laboratory methods, including microarray-based genotyping and electrospray ionization tandem mass spectrometry, to hunt for genetic variation influencing the levels of more than 350 phospho- and sphingolipid phenotypes. We identified nine novel loci, in addition to confirming a number of previously described loci. Several other genetic regions provided substantial evidence of their involvement in these traits. All of these loci are strong candidates for further research in the field of lipid biology and are likely to yield considerable insights into the complex metabolic pathways underlying circulating phospho- and sphingolipid levels. Understanding these mechanisms might help to illuminate factors leading to the development of common cardiovascular and neurological diseases and might provide molecular targets for the development of new therapies.

The majority of human proteins are post-translationally modified by covalent addition of one or more complex oligosaccharides (glycans). Alterations in glycosylation processing are associated with numerous diseases and glycans are attracting increasing attention both as disease biomarkers and as targets for novel therapeutic approaches. Using a recently developed high-throughput high-performance liquid chromatography (HPLC) analysis method, we have reported, in a pilot genome-wide association study of 13 glycan features in 2705 individuals from three European populations, that polymorphisms at three loci (FUT8, FUT6/FUT3 and HNF1A) affect plasma levels of N-glycans. Here, we extended the analysis to 33 directly measured and 13 derived glycosylation traits in 3533 individuals and identified three novel gene association (MGAT5, B3GAT1 and SLC9A9) as well as replicated the previous findings using an additional European cohort. MGAT5 (meta-analysis association P-value = 1.80 × 10(-10) for rs1257220) encodes a glycosyltransferase which is known to synthesize the associated glycans. In contrast, neither B3GAT1 (rs7928758, P = 1.66 × 10(-08)) nor SLC9A9 (rs4839604, P = 3.50 × 10(-13)) had previously been associated functionally with glycosylation of plasma proteins. Given the glucuronyl transferase activity of B3GAT1, we were able to show that glucuronic acid is present on antennae of plasma glycoproteins underlying the corresponding HPLC peak. SLC9A9 encodes a proton pump which affects pH in the endosomal compartment and it was recently reported that changes in Golgi pH can impair protein sialylation, giving a possible mechanism for the observed association.

Molecular mechanisms involved in the strengthening and formation of synapses include the activation and repression of specific genes or subsets of genes by epigenetic modifications that do not alter the genetic code itself. Chromatin modifications mediated by histone acetylation have been shown to be critical for synaptic plasticity at hippocampal excitatory synapses and hippocampal-dependent memory formation. Considering that brain-derived neurotrophic factor (BDNF) plays an important role in synaptic plasticity and behavioral adaptations, it is not surprising that regulation of this gene is subject to histone acetylation changes during synaptic plasticity and hippocampal-dependent memory formation. Whether the effects of BDNF on dendritic spines and quantal transmitter release require histone modifications remains less known. By using two different inhibitors of histone deacetylases (HDACs), we describe here that their activity is required for BDNF to increase dendritic spine density and excitatory quantal transmitter release onto CA1 pyramidal neurons in hippocampal slice cultures. These results suggest that histone acetylation/deacetylation is a critical step in the modulation of hippocampal synapses by BDNF. Thus, mechanisms of epigenetic modulation of synapse formation and function are novel targets to consider for the amelioration of symptoms of intellectual disabilities and neurodegenerative disorders associated with cognitive and memory deficits.

Background. Elevated serum uric acid (UA) is associated with gout, hypertension, cardiovascular and renal disease. Hereditary renal hypouricemia type 1 (RHUC1) is caused by mutations in the renal tubular UA transporter URAT1 and can be complicated by nephrolithiasis and exercise-induced acute renal failure (EIARF). We have recently shown that loss-of-function homozygous mutations of another UA transporter, GLUT9, cause a severe type of hereditary renal hypouricemia with similar complications (RHUC2). Methods. Two unrelated families with renal hypouricemia were clinically characterized. DNA was extracted and SLC22A12 and SLC2A9 coding for URAT1 and GLUT9, respectively, were sequenced. Transport studies into Xenopus laevis oocytes were utilized to evaluate the function of the GLUT9 mutations found. A molecular modeling study was undertaken to structurally characterize and probe the effects of these mutations. Results. Two novel homozygous GLUT9 missense mutations were identified: R171C and T125M. Mean serum UA level of the four homozygous subjects was 0.15 6 0.06 mg/dL and fractional excretion of UA was 89–150%. None of the affected subjects had nephrolithiasis, EIARF or any other complications. Transport assays revealed that both mutant proteins had a dramatically reduced ability to transport UA. Modeling showed that both R171C and T125M mutations are located within the inner channel that transports UA between the cytoplasmic and extracellular regions. Conclusions. This is the second report of renal hypouricemia caused by homozygous GLUT9 mutations. Our findings confirm the pivotal role of GLUT9 in UA transport and highlight the similarities and differences between RHUC1 and RHUC2.

Over half of all proteins are glycosylated, and alterations in glycosylation have been observed in numerous physiological and pathological processes. Attached glycans significantly affect protein function; but, contrary to polypeptides, they are not directly encoded by genes, and the complex processes that regulate their assembly are poorly understood. A novel approach combining genome-wide association and high-throughput glycomics analysis of 2,705 individuals in three population cohorts showed that common variants in the Hepatocyte Nuclear Factor 1α (HNF1α) and fucosyltransferase genes FUT6 and FUT8 influence N-glycan levels in human plasma. We show that HNF1α and its downstream target HNF4α regulate the expression of key fucosyltransferase and fucose biosynthesis genes. Moreover, we show that HNF1α is both necessary and sufficient to drive the expression of these genes in hepatic cells. These results reveal a new role for HNF1α as a master transcriptional regulator of multiple stages in the fucosylation process. This mechanism has implications for the regulation of immunity, embryonic development, and protein folding, as well as for our understanding of the molecular mechanisms underlying cancer, coronary heart disease, and metabolic and inflammatory disorders., Author Summary By combining recently developed high-throughput glycan analysis with genome-wide association study, we performed the first comprehensive analysis of common genetic polymorphisms that affect protein glycosylation. Over half of all proteins are glycosylated; but, due to difficulties in glycan analysis and the absence of a genetic template for their synthesis, knowledge about the complex processes that regulate glycan assembly is still limited. We demonstrated that HNF1α regulates the expression of key fucosyltransferase and fucose biosynthesis genes and acts as a master regulator of plasma protein fucosylation. Proper protein fucosylation is essential in numerous processes including inflammation, cancer, and coronary heart disease, thus the identification of a master regulator of plasma protein fucosylation has important implications for understanding both normal biological functions and disease processes.

Regulation of forebrain cellular structure and function by small GTPase pathways is crucial for normal and pathological brain development and function. Kalirin is a brain-specific activator of Rho-like small GTPases implicated in neuropsychiatric disorders. We have recently demonstrated key roles for kalirin in cortical synaptic transmission, dendrite branching, spine density, and working memory. However, little is known about the impact of the complete absence of kalirin on the hippocampus in mice. We thus investigated hippocampal function, structure, and associated behavioral phenotypes in KALRN knockout (KO) mice we have recently generated. Here we show that KALRN KO mice had modest impairments in hippocampal LTP, but normal hippocampal synaptic transmission. In these mice, both context and cue-dependent fear conditioning were impaired. Spine density and dendrite morphology in hippocampal pyramidal neurons were not significantly affected in the KALRN KO mice, but small alterations in the gross morphology of the hippocampus were detected. These data suggest that hippocampal structure and function are more resilient to the complete loss of kalirin, and reveal impairments in fear learning. These studies allow the comparison of the phenotypes of different kalirin mutant mice and shed light on the brain region-specific functions of small GTPase signaling.