Behavioural endophenotypes in mice lacking the auxiliary GABAB receptor subunit KCTD16

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain and is implicated in the pathophysiology of a number of neuropsychiatric disorders. The GABAB receptors are G-protein coupled receptors consisting of principle subunits and auxiliary potassium channel tetramerization domain (KCTD) subunits. The KCTD subunits 8, 12, 12b and 16 are cytosolic proteins that determine the kinetics of the GABAB receptor response. Previously, we demonstrated that Kctd12 null mutant mice (Kctd12(-/-)) exhibit increased auditory fear learning and that Kctd12(+/-) mice show altered circadian activity, as well as increased intrinsic excitability in hippocampal pyramidal neurons. KCTD16 has been demonstrated to influence neuronal excitability by regulating GABAB receptor-mediated gating of postsynaptic ion channels. In the present study we investigated for behavioural endophenotypes in Kctd16(-/-) and Kctd16(+/-) mice. Compared with wild-type (WT) littermates, auditory and contextual fear conditioning were normal in both Kctd16(-/-) and Kctd16(+/-) mice. When fear memory was tested on the following day, Kctd16(-/-) mice exhibited less extinction of auditory fear memory relative to WT and Kctd16(+/-) mice, as well as more contextual fear memory relative to WT and, in particular, Kctd16(+/-) mice. Relative to WT, both Kctd16(+/-) and Kctd16(-/-) mice exhibited normal circadian activity. This study adds to the evidence that auxillary KCTD subunits of GABAB receptors contribute to the regulation of behaviours that could constitute endophenotypes for hyper-reactivity to aversive stimuli in neuropsychiatric disorders

Characterization of Braun's lipoprotein and determination of its attachment sites to peptidoglycan by 252Cf-PD and MALDI time-of-flight mass spectrometry

A strategy for the characterization of bacterial lipoprotein-in this case Braun's lipoprotein (an outer membrane 7-ku lipoprotein) isolated from Escherichia coli —is described by time-of-flight mass spectrometric (TOF/MS) techniques [252Cf plasma desorption (PD) TOF/MS and matrix-assisted laser desorption-ionization (MALDI) TOF/MS]. Covalent linkage of lipid at the N-terminal cysteine (posttranslationally modified to a S-[2,3-bis(acyloxy)-propyl]-N-acylcysteine) and, therefore, strict insolubility in aqueous solution constitute common features for this class of proteins. Relative molecular mass determination of the major molecular species of Braun's lipoprotein was obtained by selection of an appropriate mixture of organic solvents compatible with matrix/support materials useful for the mass spectrometric techniques applied. Minor components of this lipoprotein that differ only in the fatty acid composition of the lipid anchor were detected by PD TOF/MS after enzymatic release of the extremely hydrophobic N-terminal amino acid followed by selective extraction with chloroform. Part of the primary sequence of this lipoprotein was confirmed based on peptide fragment ions observed in the positive ion PD mass spectra of cyanogen bromide-generated peptide fragments that had been isolated previously by reverse phase high-performance liquid chromatography (HPLC). Peptidoglycan fragments that represent the attachment sites of lipoprotein to peptidoglycan were enzymatically released, separated by reverse phase HPLC, and finally characterized by time-of-flight mass spectrometric techniques (252Cf-PD TOF/MS, MALDI TOF/MS). The results obtained with both techniques differed only in the better sensitivity obtained with MALDI TOF/MS, which consumed a factor of 100 to 1000 less material than with PD TOF/MS

Lung volume reduction surgery combined with cardiac interventions

Objective: Postoperative course and functional outcome were evaluated in patients who underwent lung volume reduction surgery (LVRS) or in combination with valve replacement (VR), percutaneous transluminal coronary angioplasty (PTCA), placement of a stent, or coronary artery bypass grafting (CABG). Methods: Patients with severe bronchial obstruction and hyperinflation due to pulmonary emphysema were evaluated for lung volume reduction surgery. Cardiac disorders were screened by history and physical examination and assessed by coronary angiography. Nine patients were accepted for LVRS in combination with an intervention for coronary artery disease (CAD). In addition, three patients with valve disease and severe emphysema were accepted for valve replacement (two aortic-, one mitral valve) only in combination with LVRS. Functional results over the first 6 months were analysed. Results: Pulmonary function testing demonstrates a significant improvement in postoperative FEV1 in patients who underwent LVRS combined with an intervention for CAD. This was reflected in reduction of overinflation (residual volume/total lung capacity (RV/TLC)), and improvement in the 12-min walking distance and dyspnea. Median hospital stay was 15 days (10-33). One patient in the CAD group died due to pulmonary edema on day 2 postoperatively. One of the three patients who underwent valve replacement and LVRS died on day 14 postoperatively following intestinal infarction. Both survivors improved in pulmonary function, dyspnea score and exercise capacity. Complications in all 12 patients included pneumothorax (n = 2), hematothorax (n = 1) and urosepsis (n = 1). Conclusion: Functional improvement after LVRS in patients with CAD is equal to patients without CAD. Mortality in patients who underwent LVRS after PTCA or CABG was comparable to patients without CAD. LVRS enables valve replacement in selected patients with severe emphysema otherwise inoperabl

The complete primary structure of the spermadhesin AWN, a zona pellucida-binding protein isolated from boar spermatozoa

AbstractAWN is a boar protein which originates in secretions of the male accessory glands and which becomes sperm surface-associated upon ejaculation. It is one of the components thought to mediate sperm adhesion to the egg's zona pellucida through a carbohydrate-recognition mechanism. AWN may, thus, participate in the initial events of fertilization in the pig. In this report we describe its complete primary structure by combination of protein-chemical and mass spectrometric methods. AWN exists as two isoforms, AWN-1 and AWN-2, which differ in that AWN-2 is N-terminally acetylated. The amino acid sequence of AWN contains 133 amino acid residues and two disulphide bridges between nearest-neighbour cysteine residues. Analysis of the amino acid sequence of the AWN proteins showed significant similarity only to AQN-1 and AQN-3, two other boar spermadhesins

The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Comprehensive transcriptome analysis of the highly complex Pisum sativum genome using next generation sequencing

<p>Abstract</p> <p>Background</p> <p>The garden pea, <it>Pisum sativum</it>, is among the best-investigated legume plants and of significant agro-commercial relevance. <it>Pisum sativum </it>has a large and complex genome and accordingly few comprehensive genomic resources exist.</p> <p>Results</p> <p>We analyzed the pea transcriptome at the highest possible amount of accuracy by current technology. We used next generation sequencing with the Roche/454 platform and evaluated and compared a variety of approaches, including diverse tissue libraries, normalization, alternative sequencing technologies, saturation estimation and diverse assembly strategies. We generated libraries from flowers, leaves, cotyledons, epi- and hypocotyl, and etiolated and light treated etiolated seedlings, comprising a total of 450 megabases. Libraries were assembled into 324,428 unigenes in a first pass assembly.</p> <p>A second pass assembly reduced the amount to 81,449 unigenes but caused a significant number of chimeras. Analyses of the assemblies identified the assembly step as a major possibility for improvement. By recording frequencies of Arabidopsis orthologs hit by randomly drawn reads and fitting parameters of the saturation curve we concluded that sequencing was exhaustive. For leaf libraries we found normalization allows partial recovery of expression strength aside the desired effect of increased coverage. Based on theoretical and biological considerations we concluded that the sequence reads in the database tagged the vast majority of transcripts in the aerial tissues. A pathway representation analysis showed the merits of sampling multiple aerial tissues to increase the number of tagged genes. All results have been made available as a fully annotated database in fasta format.</p> <p>Conclusions</p> <p>We conclude that the approach taken resulted in a high quality - dataset which serves well as a first comprehensive reference set for the model legume pea. We suggest future deep sequencing transcriptome projects of species lacking a genomics backbone will need to concentrate mainly on resolving the issues of redundancy and paralogy during transcriptome assembly.</p

Identification of Eps15 as Antigen Recognized by the Monoclonal Antibodies aa2 and ab52 of the Wuerzburg Hybridoma Library against Drosophila Brain

The Wuerzburg Hybridoma Library against the Drosophila brain represents a collection of around 200 monoclonal antibodies that bind to specific structures in the Drosophila brain. Here we describe the immunohistochemical staining patterns, the Western blot signals of one- and two-dimensional electrophoretic separation, and the mass spectrometric characterization of the target protein candidates recognized by the monoclonal antibodies aa2 and ab52 from the library. Analysis of a mutant of a candidate gene identified the Drosophila homolog of the Epidermal growth factor receptor Pathway Substrate clone 15 (Eps15) as the antigen for these two antibodies

Association of eGFR-Related Loci Identified by GWAS with Incident CKD and ESRD

Family studies suggest a genetic component to the etiology of chronic kidney disease (CKD) and end stage renal disease (ESRD). Previously, we identified 16 loci for eGFR in genome-wide association studies, but the associations of these single nucleotide polymorphisms (SNPs) for incident CKD or ESRD are unknown. We thus investigated the association of these loci with incident CKD in 26,308 individuals of European ancestry free of CKD at baseline drawn from eight population-based cohorts followed for a median of 7.2 years (including 2,122 incident CKD cases defined as eGFR <60ml/min/1.73m2 at follow-up) and with ESRD in four case-control studies in subjects of European ancestry (3,775 cases, 4,577 controls). SNPs at 11 of the 16 loci (UMOD, PRKAG2, ANXA9, DAB2, SHROOM3, DACH1, STC1, SLC34A1, ALMS1/NAT8, UBE2Q2, and GCKR) were associated with incident CKD; p-values ranged from p = 4.1e-9 in UMOD to p = 0.03 in GCKR. After adjusting for baseline eGFR, six of these loci remained significantly associated with incident CKD (UMOD, PRKAG2, ANXA9, DAB2, DACH1, and STC1). SNPs in UMOD (OR = 0.92, p = 0.04) and GCKR (OR = 0.93, p = 0.03) were nominally associated with ESRD. In summary, the majority of eGFR-related loci are either associated or show a strong trend towards association with incident CKD, but have modest associations with ESRD in individuals of European descent. Additional work is required to characterize the association of genetic determinants of CKD and ESRD at different stages of disease progression

Particulate matter exposure during pregnancy is associated with birth weight, but not gestational age, 1962-1992: a cohort study

<p>Abstract</p> <p>Background</p> <p>Exposure to air pollutants is suggested to adversely affect fetal growth, but the evidence remains inconsistent in relation to specific outcomes and exposure windows.</p> <p>Methods</p> <p>Using birth records from the two major maternity hospitals in Newcastle upon Tyne in northern England between 1961 and 1992, we constructed a database of all births to mothers resident within the city. Weekly black smoke exposure levels from routine data recorded at 20 air pollution monitoring stations were obtained and individual exposures were estimated via a two-stage modeling strategy, incorporating temporally and spatially varying covariates. Regression analyses, including 88,679 births, assessed potential associations between exposure to black smoke and birth weight, gestational age and birth weight standardized for gestational age and sex.</p> <p>Results</p> <p>Significant associations were seen between black smoke and both standardized and unstandardized birth weight, but not for gestational age when adjusted for potential confounders. Not all associations were linear. For an increase in whole pregnancy black smoke exposure, from the 1^st(7.4 μg/m³) to the 25^th(17.2 μg/m³), 50^th(33.8 μg/m³), 75^th(108.3 μg/m³), and 90^th(180.8 μg/m³) percentiles, the adjusted estimated decreases in birth weight were 33 g (SE 1.05), 62 g (1.63), 98 g (2.26) and 109 g (2.44) respectively. A significant interaction was observed between socio-economic deprivation and black smoke on both standardized and unstandardized birth weight with increasing effects of black smoke in reducing birth weight seen with increasing socio-economic disadvantage.</p> <p>Conclusions</p> <p>The findings of this study progress the hypothesis that the association between black smoke and birth weight may be mediated through intrauterine growth restriction. The associations between black smoke and birth weight were of the same order of magnitude as those reported for passive smoking. These findings add to the growing evidence of the harmful effects of air pollution on birth outcomes.</p