Search

beta-Ureidopropionase is the third enzyme of the pyrimidine degradation pathway and catalyses the conversion of N-carbamyl-beta-alanine and N-carbamyl-beta-aminoisobutyric acid to beta-alanine and beta-aminoisobutyric acid, ammonia and CO2. To date, only a limited number of genetically confirmed patients with a complete beta-ureidopropionase deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 10 newly identified beta-ureidopropionase deficient individuals. Patients presented mainly with neurological abnormalities and markedly elevated levels of N-carbamyl-beta-alanine and N-carbamyl-beta-aminoisobutyric acid in urine. Analysis of UPB1, encoding beta-ureidopropionase, showed 5 novel missense variants and two novel splice-site variants. Functional expression of the UPB1 variants in mammalian cells showed that recombinant beta-ureidopropionase carrying the p.Ala120Ser, p.Thr129Met, p.Ser300Leu and p.Asn345Ile variant yielded no or significantly decreased beta-ureidopropionase activity. Analysis of the crystal structure of human beta-ureidopropionase indicated that the point mutations affect substrate binding or prevent the proper subunit association to larger oligomers and thus a fully functional beta-ureidopropionase. A minigene approach showed that the intronic variants c.[364 + 6 T > G] and c.[916 + 1_916 + 2dup] led to skipping of exon 3 and 8, respectively, in the process of UPB1 pre-mRNA splicing. The c.[899C > T] (p.Ser300Leu) variant was identified in two unrelated Swedish beta-ureidopropionase patients, indicating that beta-ureidopropionase deficiency may be more common than anticipated.

Reduction of dinitrogen by molybdenum nitrogenase relies on complex metalloclusters: the [8Fe:7S] P-cluster and the [7Fe:9S:Mo:C:homocitrate] FeMo-cofactor. Although both clusters bear topological similarities and require the reductive fusion of [4Fe:4S] sub-clusters to achieve their respective assemblies, P-clusters are assembled directly on the NifD(2)K(2) polypeptide prior to the insertion of FeMo-co, which is fully assembled separately from NifD(2)K(2). P-cluster maturation involves the iron protein NifH(2) as well as several accessory proteins, whose role has not been elucidated. In the present work, two NifD(2)K(2) species bearing immature P-clusters were isolated from an Azotobacter vinelandii strain in which the genes encoding NifH and the accessory protein NifZ were deleted, and characterized by X-ray absorption spectroscopy and EPR. These analyses showed that both NifD(2)K(2) complexes harbor clusters that are electronically and structurally similar, with each NifDK unit containing two [4Fe:4S](2+/+) clusters. Binding of the accessory protein NifW parallels a decrease in the distance between these clusters, as well as a subtle change in their coordination. These results support a conformational role for NifW in P-cluster biosynthesis, bringing the two [4Fe:4S] precursors closer prior to their fusion, which may be crucial in challenging cellular contexts. Max-Planck Society; DFG SPP 1927 "Iron-Sulfur for Life" [DE 1877/1-1]; Peter und Traudl Engelhorn Stiftung; U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences [DE-AC02-76SF00515]; Bill and Melinda Gates Foundation grant BNF Cereals Phase II [OPP1143172]; Bill and Melinda Gates Foundation grant BNF Cereals Phase III [INV-005889]; U.S. Department of Energy, Office of Science, Basic Energy Science [DE-SC0010834, DE-SC0010867]; Bill & Melinda Gates Foundation [OPP1143172, INV-005889] Published version C. V. S., S. D., and L. D. would like to thank the Max-Planck Society for funding. S. D. and C. V. S. acknowledge the DFG SPP 1927 "Iron-Sulfur for Life" (project DE 1877/1-1) for funding. L. D. thanks the Peter und Traudl Engelhorn Sti.ung for funding. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. C. V. S., S. D., and L. D. gratefully acknowledge Matthew Latimer for his technical assistance during XAS measurements at beamline 9-3. George E. Cutsail III, Justin H. Henthorn, and Patricia Rodr ' iguez Mac ' ia are also thanked for their assistance in XAS data collection. E. J.-V. and A. P. G. were supported by Bill and Melinda Gates Foundation grants BNF Cereals Phase II (OPP1143172) and BNF Cereals Phase III (INV-005889). Work in the laboratories of L. C. S and D. R. D. is supported by grants from the U.S. Department of Energy, Office of Science, Basic Energy Science, DE-SC0010834 and DE-SC0010867, respectively. This work was supported, in whole or in part, by the Bill & Melinda Gates Foundation (OPP1143172, INV-005889). Under the grant conditions of the Foundation, a Creative Commons Attribution 4.0 Generic License has already been assigned to the Author Accepted Manuscript version that might arise from this submission.

The relationships between dairy cow milk-based energy status (ES) indicators and fertility traits were studied during periods 8 to 21, 22 to 35, 36 to 49, and 50 to 63 d in milk. Commencement of luteal activity (C -LA) and interval from calving to the first heat (CFH), based on frequent measurements of progesterone by the management tool Herd Navigator (DeLaval), were used as fertility traits. Energy status indicator traits were milk beta-hydroxybutyrate (BHB) concentration provided by Herd Navigator and milk fat: protein ratio, concen-tration of C18:1 cis-9, the ratio of fatty acids (FA) C18:1 cis-9 and C10:0 in test-day milk samples, and predicted plasma concentration of nonesterified fatty acids (NEFA) on test days. Plasma NEFA predictions were based either directly on milk mid-infrared spectra (MIR) or on milk fatty acids based on MIR spectra (NEFAmir and NEFAfa, respectively). The average (standard deviation) C-LA was 39.3 (+/- 16.6) days, and the average CFH was 50.7 (+/- 17.2) days. The correlations between fertility traits and ES indicators tended to be higher for multiparous (r < 0.28) than for primiparous (r < 0.16) cows. All correlations were lower in the last period than in the other periods. In period 1, correlations of C-LA with NEFAfa and BHB, respectively, were 0.15 and 0.14 for primiparous and 0.26 and 0.22 for multiparous cows. The associations between fertility traits and ES indicators indicated that negative ES during the first weeks postpartum may delay the onset of luteal activity. Milk FPR was not as good an indicator for cow ES as other indicators. According to these findings, predictions of plasma NEFA and milk FA based on milk MIR spectra of routine test-day samples and the frequent measurement of milk BHB by Herd Navigator gave equally good predictions of cow ES during the first weeks of lactation. Our results indicate that routinely measured milk traits can be used for ES evaluation in early lactation.

Bacterial membrane proteins of the SbmA/BacA family are multi-solute transporters that mediate the uptake of structurally diverse hydrophilic molecules, including aminoglycoside antibiotics and antimicrobial peptides. Some family members are full-length ATP-binding cassette (ABC) transporters, whereas other members are truncated homologues that lack the nucleotide-binding domains and thus mediate ATP-independent transport. A recent cryo-EM structure of the ABC transporter Rv1819c from Mycobacterium tuberculosis has shed light on the structural basis for multi-solute transport and has provided insight into the mechanism of transport. Here, we discuss how the protein architecture makes SbmA/BacA family transporters prone to inadvertent import of antibiotics and speculate on the question which physiological processes may benefit from multi-solute transport.

Phosphorylation is a critical post-translational modification involved in the regulation of almost all cellular processes. However, fewer than 5% of thousands of recently discovered phosphosites have been functionally annotated. In this study, we devised a chemical genetic approach to study the functional relevance of phosphosites in Saccharomyces cerevisiae. We generated 474 yeast strains with mutations in specific phosphosites that were screened for fitness in 102 conditions, along with a gene deletion library. Of these phosphosites, 42% exhibited growth phenotypes, suggesting that these are more likely functional. We inferred their function based on the similarity of their growth profiles with that of gene deletions and validated a subset by thermal proteome profiling and lipidomics. A high fraction exhibited phenotypes not seen in the corresponding gene deletion, suggestive of a gain-of-function effect. For phosphosites conserved in humans, the severity of the yeast phenotypes is indicative of their human functional relevance. This high-throughput approach allows for functionally characterizing individual phosphosites at scale. ispartof: NATURE BIOTECHNOLOGY vol:40 issue:3 pages:382-+ ispartof: location:United States status: published

The insulin-producing cells (IPCs), a group of 14 neurons in the Drosophila brain, regulate numerous processes, including energy homeostasis, lifespan, stress response, fecundity, and various behaviors, such as foraging and sleep. Despite their importance, little is known about the development and the factors that regulate morphological and functional differentiation of IPCs. In this study, we describe the use of a new transgenic reporter to characterize the role of the Drosophila L1-CAM homolog Neuroglian (Nrg), and the transmembrane Semaphorin-1a (Sema-1a) and its receptor Plexin A (PlexA) in the differentiation of the insulin-producing neurons. Loss of Nrg results in defasciculation and abnormal neurite branching, including ectopic neurites in the IPC neurons. Cell-type specific RNAi knockdown experiments reveal that Nrg, Sema-1a and PlexA are required in IPCs and glia to control normal morphological differentiation of IPCs albeit with a stronger contribution of Nrg and Sema-1a in glia and of PlexA in the IPCs. These observations provide new insights into the development of the IPC neurons and identify a novel role for Sema-1a in glia. In addition, we show that Nrg, Sema-1a and PlexA in glia and IPCs not only regulate morphological but also functional differentiation of the IPCs and that the functional deficits are likely independent of the morphological phenotypes. The requirements of nrg, Sema-1a, and PlexA in IPC development and the expression of their vertebrate counterparts in the hypothalamic-pituitary axis, suggest that these functions may be evolutionarily conserved in the establishment of vertebrate endocrine systems.

The decline of neuronal synapses is an established feature of ageing accompanied by the diminishment of neuronal function, and in the motor system at least, a reduction of behavioural capacity. Here, we have investigated Drosophila motor neuron synaptic terminals during ageing. We observed cumulative fragmentation of presynaptic structures accompanied by diminishment of both evoked and miniature neurotransmission occurring in tandem with reduced motor ability. Through discrete manipulation of each neurotransmission modality, we find that miniature but not evoked neurotransmission is required to maintain presynaptic architecture and that increasing miniature events can both preserve synaptic structures and prolong motor ability during ageing. Our results establish that miniature neurotransmission, formerly viewed as an epiphenomenon, is necessary for the long-term stability of synaptic connections., Synaptic structures disintegrate and fragment as ageing progresses. Here the authors find that miniature neurotransmission is required to maintain adult motor synapse structures in Drosophila and that increasing miniature events can preserve motor ability during ageing.

Behavioural problems are leading welfare issues in domestic dogs. In particular, anxiety-related behavioural problems, such as fearfulness and noise sensitivity are highly prevalent conditions that cause distress to fearful dogs. To better understand the environmental factors associated with non-social fear, including noise sensitivity, fear of novel situations, and fear of surfaces and heights, a large online survey including data on 13,700 Finnish pet dogs was performed by the dog owners. After fulfilling inclusion criteria, this data consisted of 9,613 dogs with fear of fireworks, 9,513 dogs with fear of thunder, 6,945 dogs with fear of novel situations, and 2,932 dogs with fear of surfaces and heights. Logistic regression analyses revealed that dogs with frequent non-social fear had experienced less socialisation during puppyhood, were more often neutered, had inexperienced owners, lived without conspecifics, participated less frequently in activities or training, and lived in more urban environments. In addition, we identified several breed differences, and a tendency of more common non-social fear in small dog breeds, which suggests a genetic background. Non-social fearfulness has a negative effect on well-being of the dogs. Our findings suggest that the socialisation and the living environment and the value of other dogs’ company and owner interaction via activities and training may improve the well-being of the dogs.

Behaviour problems and anxieties in dogs decrease their quality of life and may lead to relinquishment or euthanasia. Considering the large number of pet dogs and the commonness of these problematic behaviours, a better understanding of the epidemiology and related molecular and environmental factors is needed. We have here studied the prevalence, comorbidity, and breed specificity of seven canine anxiety-like traits: noise sensitivity, fearfulness, fear of surfaces and heights, inattention/impulsivity, compulsion, separation related behaviour and aggression with an online behaviour questionnaire answered by dog owners. Our results show that noise sensitivity is the most common anxiety-related trait with a prevalence of 32% in 13,700 Finnish pet dogs. Due to the high prevalence of noise sensitivity and fear, they were the most common comorbidities. However, when comparing the relative risk, the largest risk ratios were seen between hyperactivity/inattention, separation related behaviour and compulsion, and between fear and aggression. Furthermore, dog breeds showed large differences in prevalence of all anxiety-related traits, suggesting a strong genetic contribution. As a result, selective breeding focusing on behaviour may reduce the prevalence of canine anxieties. Anxious animals may suffer from chronic stress and thus, modified breeding policies could improve the welfare of our companion dogs.

Dyslipidemia is a major risk factor for cardiovascular disease. Although many genetic factors have been unveiled, a large fraction of the phenotypic variance still needs further investigation. Chromosome 1 (Chr 1) harbors multiple gene loci that regulate blood lipid levels, and identifying functional genes in these loci has proved challenging. We constructed a mouse population, Chr 1 substitution lines (C1SLs), where only Chr 1 differs from the recipient strain C57BL/6J (B6), while the remaining chromosomes are unchanged. Therefore, any phenotypic variance between C1SLs and B6 can be attributed to the differences in Chr 1. In this study, we assayed plasma lipid and glucose levels in 13 C1SLs and their recipient strain B6. Through weighted gene co-expression network analysis of liver transcriptome and "guilty-by-association" study, eight associated modules of plasma lipid and glucose were identified. Further joint analysis of human genome wide association studies revealed 48 candidate genes. In addition, 38 genes located on Chr 1 were also uncovered, and 13 of which have been functionally validated in mouse models. These results suggest that C1SLs are ideal mouse models to identify functional genes on Chr 1 associated with complex traits, like dyslipidemia, by using gene co-expression network analysis.

Malaltia aòrtica; Dissecció; Aneurisma aòrtic toràcic Enfermedad aórtica; Disección; Aneurisma de aorta torácica Aortic disease; Dissection; Thoracic aortic aneurysm The ACTA2 gene encodes for smooth muscle specific α-actin, a critical component of the contractile apparatus of the vascular smooth muscle cell. Pathogenic variants in the ACTA2 gene are the most frequently encountered genetic cause of non-syndromic hereditary thoracic aortic disease (HTAD). Although thoracic aortic aneurysm and/or dissection is the main clinical manifestation, a variety of occlusive vascular disease and extravascular manifestations occur in ACTA2-related vasculopathy. Current data suggest possible mutation-specific manifestations of vascular and extra-aortic traits. Despite its relatively high prevalence, comprehensive recommendations on the care of patients and families with pathogenic variants in ACTA2 have not yet been established. We aimed to develop a consensus document to provide medical guidance for health care professionals involved in the diagnosis and treatment of patients and relatives with pathogenic variants in ACTA2. The HTAD Working Group of the European Reference Network for Rare Vascular Diseases (VASCERN) convened to review current literature and discuss expert opinions on clinical management of ACTA2 related vasculopathy. This consensus statement summarizes our recommendations on diagnosis, monitoring, treatment, pregnancy, genetic counselling and testing in patients with ACTA2-related vasculopathy. However, there is a clear need for additional prospective multicenter studies to further define proper guidelines. This work was supported by the Dutch Heart Foundation (2014 T007) and by an Erasmus University Rotterdam Fellowship (I.M.B.H. van de Laar).

Porcine circovirus type 2 (PCV2) is the etiological agent of PCV2-associated diseases (PCVAD). PCV2 targets lymphoblasts, and pigs suffering from PCVAD display lymphocyte depletion in lymphoid tissues. PCV2 infection of lymphoblasts has not been studied. Here, the replication cycle of PCV2 (abortion strain 1121 and PMWS strain Stoon1010) in T-lymphoblasts was examined. The expression of Rep and Cap were found for both viral strains, while progeny virus was detected for Stoon1010 but not for 1121. PCV2 attached to 11&ndash, 26% (1121-Stoon1010) of the T-lymphoblasts while 2.6&ndash, 12.7% of cells showed virus internalization. Chondroitin sulfate (CS) was present on 25% of T-lymphoblasts, and colocalized with PCV2 on 31&ndash, 32% of the PCV2+ cells. Enzymatic removal of CS reduced PCV2 infection. PCV2 infection was decreased by chlorpromazine, cytochalasin D and Clostridium difficile toxin B for both viral strains and by amiloride for 1121 but not for Stoon1010. Inhibiting either endosome acidification or serine proteases strongly reduced PCV2 infection. Three-dimensional analysis of Cap structure demonstrated a better Cap-nucleic acid affinity for Stoon1010 than for 1121. Taken together, PCV2 binds to T-lymphoblasts partially via CS, enters via clathrin-mediated endocytosis, and disassembles under functions of a pH-drop and serine proteases. Strain Stoon1010 displayed an enhanced viral binding, a specific receptor-mediated endocytosis, an increased Cap-nucleic acid affinity, and a more productive infection in T-lymphoblasts than 1121 did, indicating an evolution from 1121 to Stoon1010.

The main objective of this study was to compare the performance of different ‘nonlinear quantile regression’ models evaluated at the τth quantile (0·25, 0·50, and 0·75) of milk production traits and somatic cell score (SCS) in Iranian Holstein dairy cows. Data were collected by the Animal Breeding Center of Iran from 1991 to 2011, comprising 101 051 monthly milk production traits and SCS records of 13 977 cows in 183 herds. Incomplete gamma (Wood), exponential (Wilmink), Dijkstra and polynomial (Ali & Schaeffer) functions were implemented in the quantile regression. Residual mean square, Akaike information criterion and log-likelihood from different models and quantiles indicated that in the same quantile, the best models were Wilmink for milk yield, Dijkstra for fat percentage and Ali & Schaeffer for protein percentage. Over all models the best model fit occurred at quantile 0·50 for milk yield, fat and protein percentage, whereas, for SCS the 0·25th quantile was best. The best model to describe SCS was Dijkstra at quantiles 0·25 and 0·50, and Ali & Schaeffer at quantile 0·75. Wood function had the worst performance amongst all traits. Quantile regression is specifically appropriate for SCS which has a mixed multimodal distribution. The main objective of this study was to compare the performance of different 'nonlinear quantile regression' models evaluated at the τth quantile (0·25, 0·50, and 0·75) of milk production traits and somatic cell score (SCS) in Iranian Holstein dairy cows. Data were collected by the Animal Breeding Center of Iran from 1991 to 2011, comprising 101 051 monthly milk production traits and SCS records of 13 977 cows in 183 herds. Incomplete gamma (Wood), exponential (Wilmink), Dijkstra and polynomial (Ali & Schaeffer) functions were implemented in the quantile regression. Residual mean square, Akaike information criterion and log-likelihood from different models and quantiles indicated that in the same quantile, the best models were Wilmink for milk yield, Dijkstra for fat percentage and Ali & Schaeffer for protein percentage. Over all models the best model fit occurred at quantile 0·50 for milk yield, fat and protein percentage, whereas, for SCS the 0·25th quantile was best. The best model to describe SCS was Dijkstra at quantiles 0·25 and 0·50, and Ali & Schaeffer at quantile 0·75. Wood function had the worst performance amongst all traits. Quantile regression is specifically appropriate for SCS which has a mixed multimodal distribution.

International audience; Maintenance of genome integrity is a key process in all organisms. DNA polymerases (Pols) are central players in this process as they are in charge of the faithful reproduction of the genetic information, as well as of DNA repair. Interestingly, all eukaryotes possess a large repertoire of polymerases. Three protein complexes, DNA Pol alpha, delta, and epsilon, are in charge of nuclear DNA replication. These enzymes have the fidelity and processivity required to replicate long DNA sequences, but DNA lesions can block their progression. Consequently, eukaryotic genomes also encode a variable number of specialized polymerases (between five and 16 depending on the organism) that are involved in the replication of damaged DNA, DNA repair, and organellar DNA replication. This diversity of enzymes likely stems from their ability to bypass specific types of lesions. In the past 10-15 years, our knowledge regarding plant DNA polymerases dramatically increased. In this review, we discuss these recent findings and compare acquired knowledge in plants to data obtained in other eukaryotes. We also discuss the emerging links between genome and epigenome replication.

Antibody class-switch recombination and somatic hypermutation critically depend on the function of activation-induced cytidine deaminase (AID). Rare variants in its gene AICDA have been reported to cause autosomal recessive AID deficiency (autosomal recessive hyper-IgM syndrome type 2 (HIGM2)). Exome sequencing of a multicase Finnish family with an HIGM2 phenotype identified a rare, homozygous, variant (c.416T > C, p.(Met139Thr)) in the AICDA gene, found to be significantly enriched in the Finnish population compared with other populations of European origin (38.56-fold, P

The Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) is the first viral latency-associated protein produced after EBV infection of resting B cells. Its role in B cell transformation is poorly defined, but it has been reported to enhance gene activation by the EBV protein EBNA2 in vitro. We generated EBNA-LP knockout (LPKO) EBVs containing a STOP codon within each repeat unit of internal repeat 1 (IR1). EBNA-LP-mutant EBVs established lymphoblastoid cell lines (LCLs) from adult B cells at reduced efficiency, but not from umbilical cord B cells, which died approximately two weeks after infection. Adult B cells only established EBNA-LP-null LCLs with a memory (CD27+) phenotype. Quantitative PCR analysis of virus gene expression after infection identified both an altered ratio of the EBNA genes, and a dramatic reduction in transcript levels of both EBNA2-regulated virus genes (LMP1 and LMP2) and the EBNA2-independent EBER genes in the first 2 weeks. By 30 days post infection, LPKO transcription was the same as wild-type EBV. In contrast, EBNA2-regulated cellular genes were induced efficiently by LPKO viruses. Chromatin immunoprecipitation revealed that EBNA2 and the host transcription factors EBF1 and RBPJ were delayed in their recruitment to all viral latency promoters tested, whereas these same factors were recruited efficiently to several host genes, which exhibited increased EBNA2 recruitment. We conclude that EBNA-LP does not simply co-operate with EBNA2 in activating gene transcription, but rather facilitates the recruitment of several transcription factors to the viral genome, to enable transcription of virus latency genes. Additionally, our findings suggest that EBNA-LP is essential for the survival of EBV-infected naïve B cells.

International audience; In the ciliate Paramecium tetraurelia, functional genes are reconstituted during development of the somatic macronucleus through the precise excision of similar to 45 000 single-copy Internal Eliminated Sequences (IESs), thought to be the degenerate remnants of ancient transposon insertions. Like introns, IESs are marked only by a weak consensus at their ends. How such a diverse set of sequences is faithfully recognized and precisely excised remains unclear: specialized small RNAs have been implicated, but in their absence up to similar to 60% of IESs are still correctly excised. To get further insight, we designed a mutagenesis screen based on the hypersensitivity of a specific excision event in the mtA gene, which determines mating types. Unlike most IES-containing genes, the active form of mtA is the unexcised one, allowing the recovery of hypomorphic alleles of essential IES recognition/excision factors. Such is the case of one mutation recovered in the Piwi gene PTIWI09, a key player in small RNA-mediated IES recognition. Another mutation identified a novel protein with a C2H2 zinc finger, mtGa, which is required for excision of a small subset of IESs characterized by enrichment in a 5-bp motif. The unexpected implication of a sequence-specific factor establishes a new paradigm for IES recognition and/or excision.

WOS:000456327800004; International audience; Agrobacterium populations live in different habitats (bare soil, rhizosphere, host plants), and hence face different environmental constraints. They have evolved the capacity to exploit diverse resources and to escape plant defense and competition from other microbiota. By modifying the genome of their host, Agrobacterium populations exhibit the remarkable ability to construct and exploit the ecological niche of the plant tumors that they incite. This niche is characterized by the accumulation of specific, low molecular weight compounds termed opines that play a critical role in Agrobacterium's lifestyle. We present and discuss the functions, advantages, and costs associated with this niche construction and exploitation.

Several non-native invertebrate and vertebrate species have been detected in the Guadiana Estuary (SW-Iberian Peninsula, Europe) during the 21st century. In June 2015, the non-native hydroid Cordylophora caspia (Pallas, 1771) was detected for the first time in this estuary, which motivated an assessment of its distribution during late Spring and Summer 2016. The main goals of this paper were to: i) report the presence of Cordylophora caspia and its distribution in the Guadiana Estuary, ii) record the substrates colonized, salinity, and water temperatures at locations where the species was detected, iii) evaluate possible introduction vectors and invasion routes; and iv) discuss the potential impacts and management options. Cordylophora caspia occupied a 25-km stretch of the estuary with salinities between 0.2 and 13.8 and occupied a variety of human-made substrates. Shipping was the most likely introduction vector of C. caspia, which might have originated from populations in the Atlantic Ocean or the Mediterranean Sea. Currently, the potential ecological impacts are likely low since the population size is small due to an apparent shortage of suitable habitat. Economic effects are minimal at present because there are no major industries along the basin extracting water from the estuary. An integrated ecohydrological approach-i.e. freshets released from dams to control the populations of Cnidaria-was proposed to minimize or mitigate the potential negative effects of this species in the Guadiana Estuary. Delta Stewardship Council; Delta Science Program [1167]; Foundation for Science and Technology (FCT, Portugal) through the Jellyfisheries project [PTDC/MAR-BIO/0440/2014]; European Regional Development Fund (COMPETE program-Operational Competitiveness Programme); FCT [SFRH/BPD/108949/2015]; [UID/Multi/04326/2013] info:eu-repo/semantics/publishedVersion

BACKGROUND: Inactivating germline mutations in the tumour suppressor gene BRCA1 are associated with a significantly increased risk of developing breast and ovarian cancer. A large number (>1500) of unique BRCA1 variants have been identified in the population and can be classified as pathogenic, non-pathogenic or as variants of unknown significance (VUS). Many VUS are rare missense variants leading to single amino acid changes. Their impact on protein function cannot be directly inferred from sequence information, precluding assessment of their pathogenicity. Thus, functional assays are critical to assess the impact of these VUS on protein activity. BRCA1 is a multifunctional protein and different assays have been used to assess the impact of variants on different biochemical activities and biological processes.METHODS AND RESULTS: To facilitate VUS analysis, we have developed a visualisation resource that compiles and displays functional data on all documented BRCA1 missense variants. BRCA1 Circos is a web-based visualisation tool based on the freely available Circos software package. The BRCA1 Circos web tool (http://research.nhgri.nih.gov/bic/circos/) aggregates data from all published BRCA1 missense variants for functional studies, harmonises their results and presents various functionalities to search and interpret individual-level functional information for each BRCA1 missense variant.CONCLUSIONS: This research visualisation tool will serve as a quick one-stop publically available reference for all the BRCA1 missense variants that have been functionally assessed. It will facilitate meta-analysis of functional data and improve assessment of pathogenicity of VUS.

The combination of investigating child and family characteristics sheds light on the constellation of risk factors that can ultimately lead to dyslexia. This family-risk study examines plausible preschool risk factors and their specificity. Participants (N∈=∈196, 42 % girls) included familial risk (FR) children with and without dyslexia in Grade 3 and controls. First, we found impairments in phonological awareness, rapid naming, and letter knowledge in FR kindergartners with later dyslexia, and mild phonological-awareness deficits in FR kindergartners without subsequent dyslexia. These skills were better predictors of reading than arithmetic, except for rapid naming. Second, the literacy environment at home was comparable among groups. Third, having a dyslexic parent and literacy abilities of the non-dyslexic parent related to offspring risk of dyslexia. Parental literacy abilities might be viewed as indicators of offspring's liability for literacy difficulties, since parents provide offspring with genetic and environmental endowment. We propose an intergenerational multiple deficit model in which both parents confer cognitive risks.

The next generation sequencing revolution has enabled rapid discovery of genetic markers, however, development of fully functioning new markers still requires a long and costly process of marker validation. This study reports a rapid and economical approach for the validation and deployment of polymorphic microsatellite markers obtained from a 454 pyrosequencing library of Atlantic cod, Gadus morhua, Linnaeus 1758. Primers were designed from raw reads to amplify specific amplicon size ranges, allowing effective PCR multiplexing. Multiplexing was combined with a three-primer PCR approach using four universal tails to label amplicons with separate fluorochromes. A total of 192 primer pairs were tested, resulting in 73 polymorphic markers. Of these, 55 loci were combined in six multiplex panels each containing between six and eleven markers. Variability of the loci was assessed on G. morhua from the Celtic Sea (n = 46) and the Scotian Shelf (n = 46), two locations that have shown genetic differentiation in previous studies. Multilocus F(ST) between the two samples was estimated at 0.067 (P = 0.001). After three loci potentially under selection were excluded, the global F(ST) was estimated at 0.043 (P = 0.001). Our technique combines three-primer and multiplex PCR techniques, allowing simultaneous screening and validation of relatively large numbers of microsatellite loci.

Summary Large numbers of inbred laboratory rat strains have been developed for a range of complex disease phenotypes. To gain insights into the evolutionary pressures underlying selection for these phenotypes, we sequenced the genomes of 27 rat strains, including 11 models of hypertension, diabetes, and insulin resistance, along with their respective control strains. Altogether, we identified more than 13 million single-nucleotide variants, indels, and structural variants across these rat strains. Analysis of strain-specific selective sweeps and gene clusters implicated genes and pathways involved in cation transport, angiotensin production, and regulators of oxidative stress in the development of cardiovascular disease phenotypes in rats. Many of the rat loci that we identified overlap with previously mapped loci for related traits in humans, indicating the presence of shared pathways underlying these phenotypes in rats and humans. These data represent a step change in resources available for evolutionary analysis of complex traits in disease models. PaperClip, Graphical Abstract, Highlights • Genomes of 27 rat strains were sequenced; >13 million sequence variants identified • Selective sweeps and coevolved gene clusters were detected in 11 disease models • Previously identified and new disease genes and pathways were identified • This is first evolutionary analysis of artificial selection for disease phenotypes, Evolution analysis of artificial selection for disease phenotypes, such as hypertension and diabetes, in 27 rat strains reveals disease-related variants and loci.

International audience; Maintaining homeostasis in higher organisms involves a complex interplay of multiple ubiquitous and organ-specific molecular mechanisms that can be characterized using functional genomics technologies such as transcriptomics, proteomics, and metabonomics and dissected out through genetic investigations in healthy and diseased individuals. We characterized the genomic, metabolic, and physiological divergence of several inbred rat strains--Brown Norway, Lewis, Wistar Kyoto, Fisher (F344)--frequently used as healthy controls in genetic studies of the cardiometabolic syndrome. Hierarchical clustering of (1)H NMR-based metabolic profiles (n = 20 for urine, n = 16 for plasma) identified metabolic phenotype (metabotype) divergence patterns similar to the phylogenetic variability based on single nucleotide polymorphisms. However, the observed urinary metabotype variation exceeded that explainable by genetic polymorphisms. To understand further this natural variation, we used an integrative, knowledge-based network biology metabolic pathway analysis approach, coined Metabolite-Set Enrichment Analysis (MSEA). MSEA reveals that homeostasis and physiological plasticity can be achieved despite widespread divergences in glucose, lipid, amino acid, and energy metabolism in the host, together with different gut microbiota contributions suggestive of strain-specific transgenomic interactions. This work illustrates the concept of natural metabolomic variation, leading to physiologically stable albeit diverse strategies within the range of normality, all of which are highly relevant to animal model physiology, genetical genomics, and patient stratification in personalized healthcare.

Fear is an emotion needed to survive, but when prolonged and frequent, causes suffering in both humans and animals. The most common forms of canine anxiety are as follows: general fearfulness, noise sensitivity, and separation anxiety are responsible for a large proportion of behavioral problems. Information on the prevalence and comorbidity of different anxieties is necessary for breeding, veterinary behavior, and also for behavioral genetic research, where accurate information of the phenotype is essential. We used a validated owner-completed questionnaire to collect information on dogs' fearfulness (toward unfamiliar people, dogs, in new situations), noise sensitivity, separation anxiety, as well as aggressive behavior. We received 3284 answers from 192 breeds. The prevalence estimate for noise sensitivity was 39.2 %, 26.2% for general fearfulness, and 17.2% for separation anxiety. The owner reported the median onset age for noise sensitivity to be 2 years and varied between 8 weeks and 10 years (N = 407). High comorbidity was observed between different anxieties: fearful dogs had a significantly higher noise sensitivity (P

SNP genotyping was supported by the Natural Environment Research Council (NERC), UK, and performed at NERC Bio-molecular Analysis Facility (NBAF) at the University of Sheffield with project number NBAF653. This study was funded by Marie Curie Initial Training Network “Understanding the evolutionary origin of biological diversity” (ITN-2008-213780 SPECIATION). F.J. acknowledges support from the Technische Universität München – Institute for Advanced Study, funded by the German Excellence Initiative and the European Union Seventh Framework Program under grant agreement no. 291763. A major focus in speciation genetics is to identify the chromosomal regions and genes that reduce hybridization and gene flow. We investigated the genetic architecture of mating behavior in the parasitoid wasp species pair Nasonia giraulti and Nasonia oneida that exhibit strong prezygotic isolation. Behavioral analysis showed that N. oneida females had consistently higher latency times, and broke off the mating sequence more often in the mounting stage when confronted with N. giraulti males compared with males of their own species. N. oneida males produce a lower quantity of the long-range male sex pheromone (4R,5S)-5-hydroxy-4-decanolide (RS-HDL). Crosses between the two species yielded hybrid males with various pheromone quantities, and these males were used in mating trials with females of either species to measure female mate discrimination rates. A quantitative trait locus (QTL) analysis involving 475 recombinant hybrid males (F2), 2148 reciprocally backcrossed females (F3), and a linkage map of 52 equally spaced neutral single nucleotide polymorphism (SNP) markers plus SNPs in 40 candidate mating behavior genes revealed four QTL for male pheromone amount, depending on partner species. Our results demonstrate that the RS-HDL pheromone plays a role in the mating system of N. giraulti and N. oneida, but also that additional communication cues are involved in mate choice. No QTL were found for female mate discrimination, which points at a polygenic architecture of female choice with strong environmental influences. Publisher PDF

Chlamydomonas reinhardtii has long been used as a model organism in studies of cell motility and flagellar dynamics. The motility of the well-conserved '9+2' axoneme in its flagella remains a subject of immense curiosity. Using high-speed videography and morphological analyses, we have characterized long-flagella mutants (lf1, lf2-1, lf2-5, lf3-2, and lf4) of C. reinhardtii for biophysical parameters such as swimming velocities, waveforms, beat frequencies, and swimming trajectories. These mutants are aberrant in proteins involved in the regulation of flagellar length and bring about a phenotypic increase in this length. Our results reveal that the flagellar beat frequency and swimming velocity are negatively correlated with the length of the flagella. When compared to the wild-type, any increase in the flagellar length reduces both the swimming velocities (by 26-57%) and beat frequencies (by 8-16%). We demonstrate that with no apparent aberrations/ultrastructural deformities in the mutant axonemes, it is this increased length that has a critical role to play in the motion dynamics of C. reinhardtii cells, and, provided there are no significant changes in their flagellar proteome, any increase in this length compromises the swimming velocity either by reduction of the beat frequency or by an alteration in the waveform of the flagella.

Neuroticism (N) scores predict psychopathology. Therefore, it is important to know how to best interpret N-scores. This paper. reviews prior interpretations, the item content of N-measures and relevant empirical studies. We propose that N-scores reflect person-specific negative affect set points. We distinguish three possible set point models. (1) The immutable set point model in which N-scores fluctuate with short-term perturbations in reaction to positive and negative experiences but always return to their person-specific set point. (2) The experience-dependent model in which an individual's set point can change during any life stage when prompted by far-reaching experiences. (3) The mixed model, a combination of the first two models, which separates the variation in neuroticism into stable and changing components. The changing component is experience-dependent. Current evidence provides little support for the immutable model. Rather, the evidence, though inconclusive, suggests that the experience-dependent or mixed model may help to explain between- and within-subject differences in N-scores across the life span. In particular. the observation that the differential consistency of N-scores tends to drop over time, but has not been shown to approach zero, is consistent with the mixed model. We discuss implications of the models and how to distinguish them empirically. (C) 2011 Elsevier Ltd. All rights reserved.

Wheat quality is an important target trait. Previous studies mainly focus on storage protein, but their contribution to quality is partial, and most loci for quality are still undetected. Wild species of wheat are valuable resources for wheat improvement and introgression lines (ILs) are the ideal materials for detecting quantitative trait loci (QTL). In this study, a set of 82 BC5 F2-6 ILs, carrying a range of introgressed chromosome segments from a synthetic hexaploid wheat Am3 (Triticum carthlicum x Aegilops tauschii), was developed and genotyped with 170 microsatellite markers. QTL analysis was performed for 14 parameters, sodium dodecyl sulfate sedimentation volume, grain protein content (GPC), grain hardness and 11 mixograph parameters, associated with end-use quality of wheat, using the materials harvested in three environments. This led to the detection of 116 QTL, with c. 95% of the positive alleles contributed by Am3. Six important and novel genomic regions for bread-making quality were found on chromosomes 2D, 3A, 4A, 4B, 5A and 6A. These loci for bread-making quality showed pleiotropy and had large positive effects on several quality parameters with no or very weak negative effect on grain yield, thus demonstrating the value of synthetic wheat as a source of useful genetic variation for the improvement of bread wheat quality.

Spinocerebellar ataxia type 7 (SCA7) represents a rare and severe autosomal dominantly inherited ataxic disorder and is among the known CAG-repeat, or polyglutamine, diseases. In contrast to other currently known autosomal dominantly inherited ataxic disorders, SCA7 may manifest itself with different clinical courses. Because the degenerative changes evolving during these different clinical courses are not well known, many neurological disease symptoms still are unexplained. We performed an initial pathoanatomical study on unconventional thick tissue sections of the brain of a clinically diagnosed and genetically confirmed adult-onset SCA7 patient with progressive visual impairments. In this patient we observed loss of myelinated fibres in distinct central nervous fibre tracts, and widespread degeneration of the cerebellum, telencephalon, diencephalon and lower brainstem. These degenerative changes offer appropriate explanations for a variety of less-understood neurological symptoms in adult-onset SCA7 patients with visual impairments: gait, stance and limb ataxia, falls, dysarthria, dysphagia, pyramidal signs, Parkinsonian features, writing problems, impairments of saccades and smooth pursuits, altered pupillary functions, somatosensory deficits, auditory deficits and mental impairments.

Background: De novo SCN8A missense mutations have been identified as a rare dominant cause of epileptic encephalopathy. We described a person with epileptic encephalopathy associated with a mosaic deletion of the SCN8A gene. Methods: Array comparative genome hybridization was used to identify chromosomal abnormalities. Next Generation Sequencing was used to screen for variants in known and candidate epilepsy genes. A single nucleotide polymorphism array was used to test whether the SCN8A variants were in cis or in trans. Results: We identified a de nova mosaic deletion of exons 2-14 of SCN8A, and a rare maternally inherited missense variant on the other allele in a woman presenting with absence seizures, challenging behavior, intellectual disability and QRS-fragmentation on the ECG. We also found a variant in SCN5A. Conclusions: The combination of a rare missense variant with a de nova mosaic deletion of a large part of the SCN8A gene suggests that other possible mechanisms for SCN8A mutations may cause epilepsy; loss of function, genetic modifiers and cellular interference may play a role. This case expands the phenotype associated with SCN8A mutations, with absence epilepsy and regression in language and memory skills. (C) 2015 Elsevier B.V. All rights reserved.

Lactobacillus plantarum has been associated with food spoilage in a wide range of products and the biofilm growth mode has been implicated as a possible source of contamination. In this study we analysed the biofilm forming capacity of L. plantarum WCFS1 and six food spoilage isolates. Biofilm formation as quantified by crystal violet staining and colony forming units was largely affected by the medium composition, growth temperature and maturation time and by strain specific features. All strains showed highest biofilm formation in Brain Heart Infusion medium supplemented with manganese and glucose. For L. plantarum biofilms the crystal violet (CV) assay, that is routinely used to quantify total biofilm formation, correlates poorly with the number of culturable cells in the biofilm. This can in part be explained by cell death and lysis resulting in CV stainable material, conceivably extracellular DNA (eDNA), contributing to the extracellular matrix. The strain to strain variation may in part be explained by differences in levels of eDNA, likely as result of differences in lysis behaviour. In line with this, biofilms of all strains tested, except for one spoilage isolate, were sensitive to DNase treatment. In addition, biofilms were highly sensitive to treatment with Proteinase K suggesting a role for proteins and/or proteinaceous material in surface colonisation. This study shows the impact of a range of environmental factors and enzyme treatments on biofilm formation capacity for selected L. plantarum isolates associated with food spoilage, and may provide clues for disinfection strategies in food industry.

Background: To sustain the global requirements for food and renewable resources, unraveling the molecular networks underlying plant growth is becoming pivotal. Although several approaches to identify genes and networks involved in final organ size have been proven successful, our understanding remains fragmentary. Results: Here, we assessed variation in 103 lines of the Zea mays B73xH99 RIL population for a set of final leaf size and whole shoot traits at the seedling stage, complemented with measurements capturing growth dynamics, and cellular measurements. Most traits correlated well with the size of the division zone, implying that the molecular basis of final leaf size is already defined in dividing cells of growing leaves. Therefore, we searched for association between the transcriptional variation in dividing cells of the growing leaf and final leaf size and seedling biomass, allowing us to identify genes and processes correlated with the specific traits. A number of these genes have a known function in leaf development. Additionally, we illustrated that two independent mechanisms contribute to final leaf size, maximal growth rate and the duration of growth. Conclusions: Untangling complex traits such as leaf size by applying in-depth phenotyping allows us to define the relative contributions of the components and their mutual associations, facilitating dissection of the biological processes and regulatory networks underneath.

Background: Synchronous multifocal tumours are commonly observed in urothelial carcinomas of the bladder. The origin of these physically independent tumours has been proposed to occur by either intraluminal migration (clonal) or spontaneous transformation of multiple cells by carcinogens (field effect). It is unclear which model is correct, with several studies supporting both hypotheses. A potential cause of this uncertainty may be the small number of genetic mutations previously used to quantify the relationship between these tumours. Methods: To better understand the genetic lineage of these tumours we conducted exome sequencing of synchronous multifocal pta urothelial bladder cancers at a high depth, using multiple samples from three patients. Results: Phylogenetic analysis of high confidence single nucleotide variants (SNV) demonstrated that the sequenced multifocal bladder cancers arose from a clonal origin in all three patients (bootstrap value 100 %). Interestingly, in two patients the most common type of tumour-associated snvs were cytosine mutations of tpc* dinucleotides (Fisher's exact test p < 10-41), likely caused by APOBEC-mediated deamination. Incorporating these results into our clonal model, we found that tpc* type mutations occurred 2-5x more often among snvs on the ancestral branches than in the more recent private branches (p < 10-4) suggesting that tpc* mutations largely occurred early in the development of the tumour. Conclusions: These results demonstrate that synchronous multifocal bladder cancers frequently arise from a clonal origin. Our data also suggests that APOBEC-mediated mutations occur early in the development of the tumour and may be a driver of tumourigenesis in non-muscle invasive urothelial bladder cancer., Scientific and Technological Research Council of Turkey (TÜBİTAK); Science Academy of Turkey through the BAGEP program

Chromosomal translocations involving the immunoglobulin (Ig) receptor loci usually disrupt and silence these loci. On the basis of observations in follicular lymphoma (FL) with downstream Ig heavy chain (IGH) class switch recombination (CSR), we hypothesized that downstream CSR-mediated chromosomal translocations would leave the V(D)J-Cmu transcription unit intact, thereby still allowing IgM expression from the IGH allele involved in the translocation. To test this hypothesis, we analyzed biallelic IGH translocations in the IgM-expressing cell line Z-138 by interphase FISH, DNA fiber-FISH, long-distance vectorette PCR, and DNA sequencing. One IGH allele was involved in a t(11;14), showing a break in the JH region that juxtaposed the El,L enhancer and the 3' Calpha enhancers to the cyclin D1 gene. The other IGH allele contained a t(8; 14) breakpoint involving the 3' end of a Sgamma region, whereas the reciprocal breakpoint at 8q24 was approximately 40 kb centromeric of MYC. Molecular analysis showed that this IGH allele harbored a normal V(D)J-Cmu complex, which is responsible for IgM expression. These data show that chromosomal breakpoints such as the t(8; 14) can occur in downstream IGH constant regions and do not necessarily interfere with Ig expression. (C) 2004 Wiley-Liss, Inc.

Gassericin A, a bacteriocin produced by Lactobacillus gasseri LA39, shows antibacterial activity against a number of Gram-positive food-borne pathogenic bacteria. Circularin A produced by Clostridium beijerinckii ATCC25752 is active against C. tyrobutyricum, a known cheese-spoilage bacterium. Both bacteriocins were purified to homogeneity from culture supernatants by reverse-phase chromatography and the subsequently determined amino acid sequences were used to clone the bacteriocin structural genes. Mature gassericin A and circularin A are class V circular bacteriocins comprised of 58 and 69 amino acid residues, respectively. Both bacteriocins are resistant to several peptidases and proteases, as are other cyclic bacteriocins. Heterologous expression of gassericin A in Escherichia coli was used to produce a non-cyclic mature peptide, which was shown to have a specific activity 173-fold lower than the circular molecule. The minimal region for production and secretion of active circularin A is comprised of five genes, as was deduced by heterologous gene expression in Enterococcus faecalis. Gassericin A and circularin A have limited mutual similarity in their primary sequences. Unlike most bacteriocins, including gassericin A, circularin A has a three-amino-acid-leader sequence.

Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici, and Verticillium wilt, caused by either Verticillium albo-atrum or Verticillium dahliae, are devastating diseases of tomato (Lycopersicon esculentum) found worldwide. Monitoring is the cornerstone of integrated pest management of any disease. The lack of rapid, accurate, and reliable means by which plant pathogens can be detected and identified is one of the main limitations in integrated disease management. In this paper, we describe the development of a molecular detection system, based on DNA array technology, for rapid and efficient detection of these vascular wilt pathogens. We show the utility of this array for the sensitive detection of these pathogens from complex substrates like soil, plant tissues and irrigation water, and samples that are collected by tomato growers in their greenhouses.

Glycoalkaloids are secondary metabolites characterised by an undesirable taste, and known to be toxic when consumed in large quantities. Their content in potato tubers should therefore be selected against and DNA markers can significantly facilitate such a process. This study was designed to describe the genetic control of the total content of glycoalkaloids (TGA) in the potato tuber and to enhance the development of DNA markers. A segregating population was constructed from tetraploid potato clones, which were characterised by divergent TGA-content. The population had a high-TGA parent, LT7, and a low-TGA parent, NT8. We used 342 Inter-Simple Sequence Repeat (ISSR) single primers or two such primer combinations and 36 Cleaved Amplified Polymorphic Sequence (CAPS) primer pairs, digested with various restriction enzymes, to amplify random PCR products. Parental clones of both populations were used to identify polymorphic PCR products for further linkage analyses with TGA-content. In these analyses, one single ISSR marker was found to be significantly associated with TGA-content. A multiple regression analysis was also carried out using a 'stepwise' procedure. In this regression analysis TGA-content was the dependent variable whereas the polymorphic PCR products and all possible two-way interactions among them were the independent variables. The resulting best model consisted of an interaction between two loci in addition to a single locus effect. This interaction suggests that the expression of TGA-content is partially modulated by two interacting loci.

Inclusive fitness benefits have been suggested to be a major selective force behind the evolution of cooperative breeding. We investigated the fitness benefits selecting for cooperative breeding in the Seychelles warbler, Acroccphalus sechellensis. A microsatellite-based genotyping method was used to determine the relatedness of subordinates to group offspring in an isolated population of Seychelles warblers. The indirect and direct breeding benefits accruing to individual subordinates were then calculated for every successful breeding event over a three-year period. We show that female subordinates frequently gained parentage and that this, combined with high levels of extragroup paternity, resulted in low levels of relatedness between subordinates and nondescendent offspring within a territory. Direct breeding benefits were found to be significantly higher than indirect kin benefits for both female and male subordinates. As predicted, female subordinates gained significantly more direct breeding opportunities and therefore higher inclusive fitness benefits by being a subordinate within a group than did males. This may explain why most subordinates in the Seychelles warbler are female.

Background: Earlier research suggests large rater differences in heritability estimates of children's depressive symptoms in the context of significant age and sex-limitation effects. Methods: With data from an ongoing, population-based twin-family study, we estimated genetic and environmental influences on children's depression with models allowing for sex-specific effects. Our assessments of twins included self-reports and ratings made by their classmate peers, their parents and their teachers, allowing estimates of genetic and environmental effects with data from different informants. Model-fitting used maximum likelihood estimation of log-transformed data from a sample of 1,366 11- and 12-year-old twin pairs. Results: Estimates of additive genetic effects were significant for both boys and girls across all four informants, and, standardized to reflect the percentage of phenotypic variance accounted for, those estimates ranged from .28 to .71. Significant effects from common environmental sources were found in ratings of teachers and parents, where, typically, one individual rated both co-twins, but neither in peer nominations nor self-ratings. The correlation of teacher and parent ratings was modest, and bivariate model-fitting found no correlation in either genetic or shared environmental effects between teacher and parental ratings. At this young age, sex-limitation effects were found only in teacher ratings, where genetic effects were greater in girls than in boys. Conclusions: Results underscore the utility of using multiple informants to measure children's behavior and provide a foundation for follow-up of these twins in later adolescence.

Background: Earlier research suggests large rater differences in heritability estimates of children's depressive symptoms in the context of significant age and sex-limitation effects. Methods: With data from an ongoing, population-based twin-family study, we estimated genetic and environmental influences on children's depression with models allowing for sex-specific effects. Our assessments of twins included self-reports and ratings made by their classmate peers, their parents and their teachers, allowing estimates of genetic and environmental effects with data from different informants. Model-fitting used maximum likelihood estimation of log-transformed data from a sample of 1,366 11- and 12-year-old twin pairs. Results: Estimates of additive genetic effects were significant for both boys and girls across all four informants, and, standardized to reflect the percentage of phenotypic variance accounted for, those estimates ranged from .28 to .71. Significant effects from common environmental sources were found in ratings of teachers and parents, where, typically, one individual rated both co-twins, but neither in peer nominations nor self-ratings. The correlation of teacher and parent ratings was modest, and bivariate model-fitting found no correlation in either genetic or shared environmental effects between teacher and parental ratings. At this young age, sex-limitation effects were found only in teacher ratings, where genetic effects were greater in girls than in boys. Conclusions: Results underscore the utility of using multiple informants to measure children's behavior and provide a foundation for follow-up of these twins in later adolescence.

The concept that adult stem cells, despite their impressive proliferative potential, are immortal has been challenged by experimental studies of hematopoietic stem cells. In this review, we discuss the properties that characterize a stem cell, the growing list of tissues in which stem cells are found, how they can be identified and isolated, how stem cells may transdifferentiate, and the findings that illustrate how age affects the hematopoietic stem cell population. We propose that an aging stem cell population affects tissue and organ homeostasis, particularly in response to environmental stresses, and we hypothesize that through this mechanism the functional status of stem cells affects the longevity of the organism.

Factors that trigger human infection with animal influenza virus progressing into a pandemic are poorly understood. Within a project developing an evidence-based risk assessment framework for influenza viruses in animals, we conducted a review of the literature for evidence of human infection with animal influenza viruses by diagnostic methods used. The review covering Medline, Embase, SciSearch and CabAbstracts yielded 6,955 articles, of which we retained 89; for influenza A(H5N1) and A(H7N9), the official case counts of the World Health Organization were used. An additional 30 studies were included by scanning the reference lists. Here, we present the findings for confirmed infections with virological evidence. We found reports of 1,419 naturally infected human cases, of which 648 were associated with avian influenza virus (AIV) A(H5N1), 375 with other AIV subtypes, and 396 with swine influenza virus (SIV). Human cases naturally infected with AIV spanned haemagglutinin subtypes H5, H6, H7, H9 and H10. SIV cases were associated with endemic SIV of H1 and H3 subtype descending from North American and Eurasian SIV lineages and various reassortants thereof. Direct exposure to birds or swine was the most likely source of infection for the cases with available information on exposure.

Homologous recombination is a crucial mechanism that repairs a wide range of DNA lesions, including the most deleterious ones, double-strand breaks (DSBs). This multistep process is initiated by the resection of the broken DNA ends by a multisubunit helicase-nuclease complex exemplified by Escherichia coli RecBCD, Bacillus subtilis AddAB, and newly discovered Mycobacterium tuberculosis AdnAB. Here we show that in Streptomyces , neither recBCD nor addAB homologues could be detected. The only putative helicase-nuclease-encoding genes identified were homologous to M. tuberculosis adnAB genes. These genes are conserved as a single copy in all sequenced genomes of Streptomyces . The disruption of adnAB in Streptomyces ambofaciens and Streptomyces coelicolor could not be achieved unless an ectopic copy was provided, indicating that adnAB is essential for growth. Both adnA and adnB genes were shown to be inducible in response to DNA damage (mitomycin C) and to be independently transcribed. Introduction of S. ambofaciens adnAB genes in an E. coli recB mutant restored viability and resistance to UV light, suggesting that Streptomyces AdnAB could be a functional homologue of RecBCD and be involved in DNA damage resistance.