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Lowbush blueberry (Vaccinium angustifolium Aiton) is a wild, but cultivated for profit, agricultural system grown primarily in the northeastern regions of North America. It has been suggested that a functional gender specialization may be occurring in this hermaphroditic species in which some individuals (termed clones) effectively function as bearers (high ovule production but little or nonviable pollen) or as pollen donors (low ovule number with high quantities of viable pollen). The purpose of this study was to investigate if functional gender specialization was occurring in a randomly chosen population of 56 clones from the Blueberry Hill Research Farm in Jonesboro, Maine. For each clone, the mean number of ovules and the mean number of viable microspores per flower were determined. From this, functional gender was calculated. Five out of 56 clones, or approximately 10% of clones, were found to be functioning primarily as females, owing to their low levels of viable pollen. Thus, some evidence was found of a functional gender specialization occurring--the presence of a few plants that were nearly male-sterile. Since the most common evolutionary pathway to gynodioecy involves the invasion of male steriles, it is interesting to speculate that a trend towards gender dimorphism could be occurring in lowbush blueberry. Key words: fertility, ovules, pollen viability, hermaphrodite, functional gender, breeding system. Le bleuet nain vivant a l'etat sauvage est egalement cultive de facon profitable, selon un systeme agricole pratique surtout dans les regions du nord-est de l'Amerique du Nord. On a suggere qu'une specialisation fonctionnelle des genres puisse exister chez cette espece hermaphrodite chez laquelle certains individus (appele clones) fonctionneraient comme porteurs (forte production d'ovules, mais peu ou pas de pollen viable) ou donneur de pollen (faible nombre d'ovules avec de grandes quantites de pollens viables). Les auteurs se sont propose d' examiner si la specialisation fonctionnelle des genres se presente chez une population choisie au hasard, constituee de 56 clones provenant de la Blueberry Research Farm, a Jonesboro dans le Maine. Ils ont determine pour chaque clone le nombre moyen d'ovules et de microspores viables par fleur, et ils ont calcule a partir de ces donnees les genres fonctionnels. On a constate que cinq des 56 clones, environ 10 %, fonctionnent surtout comme femelles, du surtout a la faible production de pollen viable. Ainsi, les auteurs ont trouve une certaine preuve de l'existence d'une specialisation des genres, soit la presence de quelques plantes a sterilite male presque totale. Puisque le cheminement evolutif le plus commun vers la gynodiecie implique la sterilite male, il est devient interessant de speculer qu' il pourrait exister une tendance vers le dimorphisme des genres chez le bleuet nain. Mots-cles : fertilite, ovules, viabilite du pollen, hermaphrodite, genre fonctionnel, systeme de croisement. [Traduit par la Redaction], Introduction The enormous modular plasticity and the range of phenotypic expression in plants, particularly in relation to the evolution and maintenance of breeding systems, is well known (Linnaeus 1737; Darwin [...]

Introduction The receptor for advanced glycation end products (RAGE) is a multiligand glycoprotein that is upregulated at sites of pathology. (1) The ligands binding to RAGE include advanced glycation end [...], Background: The receptor for advanced glycation end products (RAGE) is the main receptor for S100B, an astrogial proinflammatory mediator that has been suggested to be involved in the pathophysiology of schizophrenia. To further elucidate the possible relevance of inflammation for mental functions, we investigated a functional polymorphism in the gene coding for RAGE in relation to personality traits and susceptibility to schizophrenia. Methods: We studied the Gly82Ser polymorphism (rs2070600, 244G>A) in 2 population-based cohorts of middle-aged participants assessed using the Karolinska Scales of Personality. In addition, we compared genotype frequencies between patients with schizophrenia and controls. Results: The population-based cohorts included 270 women and 247 men, and the case-control study involved 138 patients with schizophrenia and 258 controls. In the population-based cohorts, 82Ser carriers were found to have significantly higher scores for the psychoticism personality trait comprising the detachment and suspicion subscales. The case-control study revealed that the 82Ser allele was significantly more frequent among patients than controls. Limitations: This study was limited by the modest sample size and the use of a self-report measure to assess personality traits. Conclusion: Our findings suggest that the proven relation between certain personality traits and schizophrenia can at least to some extent be explained on a genetic level. Also, the activated S100B-RAGE axis may be an underlying cause, not only a consequence, of the disease.

Introduction In mammals, the synthesis of triacylglycerol (TAG) serves a critical function in multiple important physiological processes, including intestinal nutrition absorption, surplus energy storage in cells, lactation, attenuation of lipotoxicity, [...], Monoacylglycerol acyltransferase (MGAT3, also known as MOGAT3) catalyzes the synthesis of diacylglycerol (DAG) using 2-monoacylglycerol and fatty acyl coenzyme A. This enzymatic reaction is believed to be an essential and rate-limiting step for the absorption of dietary fat in the small intestine. However, similar research for the bovine MOGAT3 gene is lacking. Therefore, in this paper, polymorphisms of the bovine MOGAT3 gene were detected in 1145 individuals from five cattle breeds by DNA pooling, PCR-RFLP, and DNA sequencing methods. The results showed that 26 novel SNPs were identified, which included 16 mutations in the coding region and the others in the introns. Additionally, association analysis between two missense mutations, g.A229G and g.G1627A, and growth traits in Nanyang cattle up to 2 years of age and adult Qinchuan cattle was performed. The results indicated that polymorphisms were significantly associated with Nanyang cattle, but no convincing associations were observed for Qinchuan cattle for the studied traits. Key words: cattle, growth traits, MOGAT3 gene, PCR-RFLP, SNP association. La monoacylglycerol acyltransferase (MGAT3, aussi connue comme MOGAT3) catalyse la synthese du diacylglycerol (DAG) a partir de 2-monoacylglycerol et d'acyl coenzyme A. Cette reaction enzymatique serait une etape essentielle et limitante pour l'absorption des lipides alimentaires dans l'intestin grele. Cependant, des etudes semblables manquent pour le gene MOGAT3 chez les bovins. Dans ce travail, les polymorphismes au sein du gene MOGAT3 des bovins ont ete detectes chez 1145 individus provenant des cinq races en etudiant des composites d'ADN par PCR-RFLP et par sequencage. Vingt-six nouveaux SNP ont ete identifies incluant 16 mutations au sein de regions codantes, les autres mutations etant dans des introns. De plus, des analyses d'association entre deux mutations faux-sens, g.A229G et g.G1627A, et des caracteres de croissance chez les bovins Nanyang age de moins de deux ans et chez des bovins Qinchuan adultes ont ete realisees. Les resultats indiquent que les polymorphismes etaient significativement associes chez les bovins Nanyang, tandis qu'aucune association convaincante n'a ete obtenue chez les bovins Qinchuan. Mots-cles : bovins, caracteres de croissance, gene MOGAT3, PCR-RFLP, associations des SNP. [Traduit par la Redaction]

Previous work has shown that the odour of Drosophila food potently attracts adult D. melanogaster vinegar flies and that DEET blocks this attraction (5,7). The behavioural effects of DEET require [...], Blood-feeding insects such as mosquitoes are efficient vectors of human infectious diseases because they are strongly attracted by body heat, carbon dioxide and odours produced by their vertebrate hosts. Insect repellents containing DEET (JV,JV-diethyl-meta-toluamide) are highly effective, but the mechanism by which this chemical wards off biting insects remains controversial despite decades of investigation (1-11). DEET seems to act both at close range as a contact chemorepellent, by affecting insect gustatory receptors (12), and at long range, by affecting the olfactory system (1-11). Two opposing mechanisms for the observed behavioural effects of DEET in the gas phase have been proposed: that DEET interferes with the olfactory system to block host odour recognition (1-7) and that DEET actively repels insects by activating olfactory neurons that elicit avoidance behaviour (8-11). Here we show that DEET functions as a modulator of the odour-gated ion channel formed by the insect odorant receptor complex (13,14). The functional insect odorant receptor complex consists of a common co-receptor, ORCO (ref. 15) (formerly called OR83B; ref. 16), and one or more variable odorant receptor subunits that confer odour selectivity (17). DEET acts on this complex to potentiate or inhibit odour-evoked activity or to inhibit odour-evoked suppression of spontaneous activity. This modulation depends on the specific odorant receptor and the concentration and identity of the odour ligand. We identify a single amino-acid polymorphism in the second transmembrane domain of receptor OR59B in a Drosophila melanogaster strain from Brazil that renders OR59B insensitive to inhibition by the odour ligand and modulation by DEET. Our data indicate that natural variation can modify the sensitivity of an odour-specific insect odorant receptor to odour ligands and DEET. Furthermore, they support the hypothesis that DEET acts as a molecular 'confusant' that scrambles the insect odour code, and provide a compelling explanation for the broad-spectrum efficacy of DEET against multiple insect species.

Introduction The genetic basis of the sex-specific 'master regulatory switch' is incompletely understood in fishes at the present time, including species in the teleost family Salmonidae (Davidson et al. 2009). [...], Current data on the Y-specific sex-determining region of salmonid fishes from genera Salvelinus, Salmo, and Oncorhynchus indicate variable polymorphisms in the homologous chromosomal locations of the sex-specific determining region. In the majority of the Atlantic lineage Arctic charr, including populations from the Fraser River, in Labrador Canada, as well as Swedish and Norwegian strains, the sex-determining locus maps to linkage group AC-4. Previously, sex-linked polymorphisms (i.e., variation in the associated sex-linked markers on AC-4) have been described in Arctic charr. Here, we report further evidence for intraspecific sex linkage group polymorphisms in Arctic charr (i.e., the detection of the SEX locus on either the AC-1 or AC-21 linkage group) and a possible conservation of a sex linkage arrangement in Icelandic Arctic charr and Atlantic salmon, involving sex-linked markers on the AC-1/21 homeologs and the European AS-1/6 homeologous linkage groups in Atlantic salmon. The evolutionary origins for the multiple sex-determining regions within the salmonid family are discussed. We also relate the variable sex-determining regions in salmonids to their ancestral prototeleost karyotypic origins and compare these findings with what has been observed in other teleost species in general. Les donnees actuelles sur la region du chromosome Y determinant le sexe chez les salmonides appartenant aux genres Salvelinus, Salmo et Oncorhynchus indiquent qu'il y aurait des polymorphismes variables au sein des regions chromosomiques homologues de la region determinant le sexe. Chez la majorite des populations atlantiques de l'omble chevalier, incluant les populations de la Fraser River du Labrador (Canada), ainsi que celles de la Suede et de la Norvege, le locus determinant le sexe serait situe sur le groupe de liaison AC-4. Auparavant, des polymorphismes lies au sexe (c'est-a-dire de la variation associee aux marqueurs lies au sexe sur AC-4) ont ete decrits chez l'omble chevalier. Dans ce travail, les auteurs rapportent des evidences additionnelles pour du polymorphisme intraspecifique pour ce qui est du groupe de liaison determinant le sexe, c'est-a-dire la detection du locus SEX sur les groupes de liaison AC-1 ou AC-21 ainsi qu'une possible conservation de la liaison au sexe chez les populations islandaises d'omble chevalier et de saumon atlantique, laquelle impliquerait des marqueurs lies au sexe sur les homeologues AC-1/21 et les groupes homeologues AS-1/6 chez le saumon atlantique. Les auteurs discutent des origines evolutives des multiples regions determinant le sexe chez les salmonides. Les auteurs tissent egalement un lien entre la variabilite des regions determinant le sexe chez les salmonides et leurs origines caryotypiques chez l' ancetre proto-teleosteen et ils comparent ces decouvertes avec ce qui a ete observe chez d' autres especes de teleosteens en general. Mots-cles : salmonides, chromosomes sexuels, variation intraspecifique, homologie, duplication genomique. [Traduit par la Redaction]

Acacia tortilis (Forsskal) Hayne subsp. raddiana (Savi) Brenan [Acacia raddiana Savi s.s.] is the most widely spread woody legume in desert regions of Algeria. As a well-adapted species, it represents a good potential for forestation or reforestation in these areas. Its capacity to establish a nitrogen-fixing symbiosis with rhizobia constitutes an important characteristic for its development and its adaptation to such environmental conditions. For these reasons, the authors have conducted a study on the prevalence of the symbiosis in this species and on the characterization of their associated rhizobial strains. The evaluation of 101 plants from nine natural sites and eight nurseries revealed that nitrogen-fixing nodules are generally present in A. tortilis subsp. raddiana, despite the harsh edaphic conditions prevailing in natural and nursery environments of southern Algeria. Symbiotic characterization of 51 strains of rhizobia associated with A. tortilis subsp. raddiana allowed to demonstrate that these are not very specific and can, for most of them, form nitrogen-fixing nodules in other acacias species of Algerian desert areas, namely Acacia seyal Del. and Acacia ehrenbergiana Hayne. Therefore, these strains have a potential for inoculum production for inoculation of A. tortilis subsp. raddiana as well as other species of acacias. Analysis of restriction patterns of RNA 16S genes of these rhizobia strains allowed to demonstrate their wide diversity. They were essentially represented by species of the genus Ensifer, mainly Ensifer meliloti, and less so by species of Mesorhizobium and Rhizobium genera, as already documented by several authors in other parts of Africa. In addition to the rhizobia species already recognized as associate of A. tortilis subsp. raddiana, the authors have isolated five strains that could not be identified, using polymerase chain reaction--restriction fragment length polymorphism of RNA 16S gene, and that might represent a new genotypic species. Key words: Acacia tortilis subsp. raddiana, desert areas, Algeria, nurseries, nodulation, nitrogen fixation, rhizobia associates. L'Acacia tortilis (Forsskal) Hayne subsp. raddiana (Savi) Brenan [Acacia raddiana Savi s. s.] est la legumineuse ligneuse la plus repandue dans les regions desertiques d'Algeerie. En tant qu'espece bien adaptee, elle offre un potentiel d'interet pour le boisement ou le reboisement de ces regions. Sa capacite d'etablir une symbiose fixatrice d'azote avec les rhizobia constitue un caractere important pour son developpement et son adaptation aux conditions du milieu. Pour ces raisons, nous avons mene une etude portant sur la prevalence de la symbiose chez cette espece et sur la caracterisation des souches de rhizobia associees. L'etude a porte sur 101 plants provenant de neuf sites naturels et de huit pepinieres et nous a permis d'etablir que l'A. tortilis subsp. raddiana est generalement nodule; et fixateur d'azote, malgre les conditions edaphiques defavorables qui prevalent en milieu naturel et dans les pepinieres du sud du pays. La caracterisation symbiotique de 51 souches de rhizobia associees a l'A. tortilis subsp. raddiana nous a permis de montrer que celles-ci ne sont pas tres specifiques et qu'elles sont capables, pour la plupart, de former des nodules fixateurs d'azote chez les autres especes d'acacias des regions desertiques de l'Algerie, en particulier l'Acacia seyal Del. et l'Acacia ehrenbergiana Hayne. Ces souches representent donc un potentiel pour la production d'inoculants destines a la bacterisation de l'A. tortilis subsp. raddiana, mais egalement des autres especes d'acacias. L'analyse des profils de restriction du gene de l'ARN 16S des souches de rhizobia associees a permis de mettre en evidence leur grande diversite. Elles etaient representees essentiellement par les especes du genre Ensifer avec une predominance de l'Ensifer meliloti et, dans une moindre mesure, par des especes des genres Mesorhizobium et Rhizobium, comme cela a deja ete rapporte par de nombreux auteurs dans d'autres regions d'Afrique. En plus des especes de rhizobia reconnues comme etant capables de s'associer avec l'A. tortilis raddiana, nous avons isole cinq souches que nous n'avons pas pu identifier, par reaction en chaine de la polymerase--polymorphisme de la longueur du fragment de restriction du gene de l'ARN 16S, et qui pourraient constituer une nouvelle espece genotypique. Mots-cles: Acacia tortilis subsp. raddiana, regions desertiques, Algerie, pepinieres, nodulation, fixation d'azote, rhizobia associes., Introduction Les acacias autochtones des regions desertiques d'Algerie (Afrique du Nord) sont represents par six taxons: l'Acacia tortilis (Forsskal) Hayne subsp. raddiana (Savi) Brenan, l'Acacia ehrenbergiana Hayne, l'Acacia seyal Del., [...]

Introduction Resistance (R) genes cloned from a wide range of plant species and conferring resistance to a diverse spectrum of pathogens have revealed remarkable similarities in general structure and conservation [...], Disease resistance (R) genes are intriguing in their evolution and diversity patterns because of their constant interactions with evolving pathogens. In this study, we demonstrate the use of resistance gene analog (RGA) markers to estimate genetic diversity among 13 populations (118 genotypes) of Triticum dicoccoides collected along a natural aridity gradient in Israel. The diversity patterns of 204 markers derived from two R-gene domains, nucleotide binding site (NBS) and leucine-rich repeat (LRR), were compared and contrasted. Diversity patterns of NBS domain markers differed significantly from those of the LRR domain. NBS markers showed higher between-population diversity (Ft = 0.58), while LRR markers showed higher within-population diversity (F.sub.st] = 0.35). Gene diversity (He) values were twofold higher in the LRR domain than in the NBS domain (0.144 vs. 0.067). LRR [H.sub.e] values were correlated with precipitation in the spring (r = 0.8, p = 0.01), while NBS [H.sub.e] values showed no correlation with any ecogeographical variable. The evolutionary and applicative inferences of these findings are discussed. The current study demonstrates that RGA profiling is an excellent tool for studying diversity of R genes in natural plant populations. Key words: disease resistance genes, genetic diversity, RGA markers, Triticum dicoccoides, NBS, LRR. Les genes de resistance aux maladies (R) sont interessants en ce qui a trait a leur evolution et diversite en raison de leur interaction constante avec des agents pathogenes qui evoluent. Dans ce travail, les auteurs emploient des analogues de genes de resistance (RGA) comme marqueurs pour mesurer la diversite genetique au sein de 13 populations (118 genotypes) du Triticum dicoccoides recoltees le long d'un gradient d'aridite en Israel. La repartition de la diversite documentee a l'aide de 204 marqueurs provenant de deux domaines de genes R, les sites de liaison de nucleotides (NBS) et les regions riches en leucine (LRR), a ete comparee et contrastee. La diversite revelee au moyen des marqueurs a domaine NBS etait significativement differente de celle revelee au moyen de marqueurs a domaine LRR. Les marqueurs a domaine NBS ont produit une diversite inter-population plus grande ([F.sub.t] = 0,58) tandis que les marqueurs a domaine LRR revelaient une plus grande diversite intea-population ([F.sub.st] = 0,35). La diversite genique (He) etait deux fois plus grande avec les marqueurs a domaine LRR qu'avec les marqueurs a domaine NBS (0,144 vs 0,067). Les indices He des marqueurs a domaine LRR etaient correles avec la precipitation printaniere (r = 0,8; p = 0,01), tandis que les indices He des marqueurs a domaine NBS ne montraient aucune correlation avec les variables eco-geographiques. Les inferences appliquees et evolutives de ces observations sont discutees. La presente etude demontre que l'analyse des RGA constitue un excellent outil pour etudier la diversite des genes R au sein de populations naturelles de plantes. Mots-cles : genes de resistance aux maladies, diversite genetique, marqueurs RGA, Triticum dicoccoides, NBS, LRR. [Traduit par la Redaction]

Introduction Pleurotus pulmonarius (Fr.) Quel. is one of the main commercial species of oyster mushroom (Pleurotus spp.) that is cultivated around the world. The global market of edible cultivated mushrooms [...], In the cultivation of edible mushrooms, including Pleurotus pulmonarius (Fr.) Quel., the enormous number of spores produced by fruiting bodies can adversely affect mushroom growers' health, mushroom cultivation facilities, and the genetic diversity of natural populations. In this study, we constructed a primary genetic linkage map and identified the locus associated with the sporulation-deficient (sporeless) mutation of P. pulmonarius using 150 progeny isolates derived from a cross between sporeless and wild-type isolates. Based on the segregation of 300 AFLP markers, two mating-type factors, and the sporeless trait, a linkage map was generated consisting of 12 linkage groups. The map covered a total genetic distance of 971 cM, with an average marker interval of 5.2 cM. The gene region responsible for the sporeless mutation was located in linkage group II including 40 AFLP markers and the A mating-type factor locus. Of these markers, the nearest marker to the sporeless locus was located 1.4 cM away. Construction of this P. pulmonarius genetic linkage map and identification of markers that are closely linked to the sporeless locus will facilitate marker-assisted selective breeding of a sporeless strain with economically important traits. Key words: sporulation-deficient mutation, Pleurotus pulmonarius, mushroom breeding, linkage analysis, DNA marker. Dans la production de champignons comestibles, incluant le Pleurotus pulmonarius (Fr.) Quel., le nombre enorme de spores produites par les sporophores peut avoir des incidences negatives sur la sante des travailleurs, les infrastructures de production et la diversite genetique des populations naturelles. Dans ce travail, les auteurs ont produit une carte genetique primaire et identifie le locus associe a la mutation conferant un defaut de sporulation (sporeless) chez le P. pulmonarius au moyen de 150 isolats derives d'un croisement entre un isolat sporeless et un isolat de type sauvage. Sur la base de la segregation de 300 marqueurs AFLP, de deux locus de type sexuel (<< mating-type >>) et du caractere sporeless, une carte genetique a ete generee et celle-ci est composee de 12 groupes de liaison. La carte totalise 971 cM et la distance moyenne entre les marqueurs est de 5,2 cM. La region genique responsable de la mutation sporeless a ete localisee sur le groupe de liaison II, lequel comprend 40 marqueurs AFLP et le locus du type sexuel A. De ces marqueurs, le plus proche etait a 1,4 cM du locus sporeless. La construction de cette carte pour le P. pulmonarius et l'identification de marqueurs qui sont etroitement lies au locus sporeless facilitera la selection assistee de marqueurs d'une souche sporeless combinant des caracteres importants au plan economique. Mots-cles : mutation deficiente pour la sporulation, Pleurotus pulmonarius, selection de champignons, analyse de liaison genetique, marqueur d'ADN. [Traduit par la Redaction]

Byline: M. Ozdemir ABSTRACT Pit-1 gene has been identified as the pituitary specific transcription factor that regulates the expression of the growth hormone (GH) and prolactin (PRL) genes in the [...]

Byline: M. Ozdemir ABSTRACT Pit-1 gene has been identified as the pituitary specific transcription factor that regulates the expression of the growth hormone (GH) and prolactin (PRL) genes in the [...]

Cumulative lead exposure has been shown to be associated with a widened pulse pressure (PP), a marker of arterial stiffness and a predictor of cardiovascular disease. Polymorphisms in the hemochromatosis [...]

Polymorphisms in the pathogen recognition receptor gene N0D2, found in 10-20% of j North American individuals with Crohn's disease, increase the risk of developing the condition. Findings by Meher Rahman [...]