994 resultados para Functional requirements
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Summary : The skin is a complex organ that protects the body against entry of pathogens and supplies a relatively dry and impermeable barrier to water loss. This barrier function is mainly provided by the epidermis, which is the outermost layer of the skin. Serine proteases are involved in skin physiology and it is known that mutations or alterations in their expression can lead to skin diseases. In order to investigate the importance of the regulated expression of CAPI/Prss8, a membrane bound serine protease expressed in the epidermis, we developed transgenic mice ectopically expressing CAPI/Prss8 in the skin. These animals exhibited a phenotype characterized by scaly skin, epidermal hypertrophy, inflammation and scratching behavior. This phenotype could be completely abolished in mice lacking the proteinase activated receptor 2 (PAR2) revealing PAR2 as a potential in vivo downstream target of CAP 1 /Prss8. We could also provide evidence of a CAP1 /Prss8 function independent of its catalytic activity. Additionally, mice ectopically expressing PAR2 in the skin developed a skin phenotype very similar to CAPI/Prss8 transgenic animals, supporting the hypothesis of PAR2 activation by CAPI/Prss8. We could furthermore demonstrate an inhibitory effect of the serine protease inhibitor nexin-I on CAPI/Prss8, since nexin-1 transgenic expression negated the skin phenotype observed in CAPI/Prss8 transgenic mice. CAP1/Prss8 and PAR2 transgenic animals, and the understanding of the interaction between CAPl/Prss8 and PAR2, can be helpful in developing potential CAPI/Prss8 and PAR2 inhibitory molecules that may be used as drugs to treat ichthyoses-like skin diseases. Résumé : La peau est un organe complexe qui protège le corps contre l'entrée des pathogènes et forme une barrière imperméable qui empêche la déshydratation. Cette fonction de barrière est surtout fournie par l'épiderme, la couche la plus superficielle de la peau. Le bon fonctionnement de cet organe est permis, entre autres, par les protéases à sérine qui sont des enzymes dont l'altération peut causer des maladies de la peau. Pour étudier l'importance de la régulation de CAP1/Prss8, une protéase à sérine exprimée au niveau de l'épiderme, des souris génétiquement modifiées, dans lesquelles CAP1/Prss8 est exprimé d'une manière ectopique dans la peau, ont été générées. Les animaux transgéniques pour CAP1/Prss8 présentent une peau squameuse, un épiderme hypertrophique, des processus inflammatoires et se grattent. Ce phénotype a pu être complètement guéri lorsque le gène de PAR2, un récepteur qui règle l'activité des cellules de l'épiderme, est inactivé chez la souris. Ceci montre que PAR2 est une cible de CAP1/Prss8 dans le système étudié. Des études expérimentales suggèrent de plus que l'effet de CAP1/Prss8 dans ce modèle ne dépend pas de son activité enzymatique. En dernière analyse, il a été démontré que l'expression transgénique de nexin-1, un inhibiteur des protéases à sérine exprimé dans la peau, a la capacité d'améliorer la peau squameuse et l'épiderme hypertrophique causés par CAP1/Prss8 transgénique. Les animaux transgéniques pour CAP1/Prss8 et PAR2, et la compréhension du mécanisme d'interaction entre eux, pourraient aider à développer et à tester des molécules inhibitrices de CAP1 /Prss8 et PARI qui pourraient alors être utilisées comme médicaments pour traiter des maladies de la peau comme les ichthyoses.
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In the pathogenesis of type 2 diabetes, hyperglycemia appears when ß cell mass and insulin secretory capacity are no longer sufficient to compensate for insulin resistance. The reduction in ß cell mass results from increased apoptosis. Therefore, finding strategies to preserve ß cell mass and function may be useful for the treatment or prevention of diabetes. Glucagon-like peptide-1 (GLP-1) protects ß cells against apoptosis, increases their glucose competence, and induces their proliferation. Previous studies in the lab of Prof. Bernard Thorens showed that the GLP-1 anti- apoptotic effect was mediated by robust up-regulation of IGF-1R expression, and this was paralleled with an increase in Akt phosphorylation. This effect was dependent not only on increased IGF-1R expression but also on the autocrine secretion of insulin-like growth factor 2 (IGF2). They also demonstrated that GLP-1 up-regulated IGF-1R expression by a protein a kinase A-dependent translational control mechanism. The main aim of this PhD work has been to further investigate the role of the IGF2/IGF-1 Receptor autocrine loop in ß cell function and to determine the physiological role of IGF2 in ß cell plasticity and its regulation by nutrients. This PhD thesis is divided in 3 chapters. The first chapter describes the role of IGF2/IGF-1R autocrine loop in ß cell glucose competence and proliferation. Here using MIN6 cells and primary mouse islets as an experimental model we demonstrated that the glucose competence of these cells was dependent on the level of IGF-1R expression and on IGF2 secretion. Furthermore, we showed that GLP-1-induced primary ß cell proliferation was significantly reduced by Igf-lr gene inactivation and by IGF2 immunoneutralization or knockdown. In the second chapter we examined the role of this IGF2/IGF-1R autocrine loop on the ß cell functional plasticity during ageing, pregnancy, and in response to acute induction of insulin resistance using mice with ß cell-specific inactivation of ig/2. Here we showed a gender-dependent role of ß cell IGF2 in ageing and high fat diet-induced metabolic stress; we demonstrated that the autocrine secretion of IGF2 is essential for ß cell mass adaptation during pregnancy. Further we also showed that this autocrine loop plays an important role in ß cell expansion in response to acute induction of insulin resistance. The aim of the third chapter was to investigate whether we can modulate the expression and secretion of IGF2 by nutrients in order to increase the activity of autocrine loop. Here we showed that glutamine induces IGF2 biosynthesis and its fast secretion through the regulated pathway, a mechanism enhanced in the presence of glucose. Furthermore, we demonstrated that glutamine-mediated Akt phosphorylation is dependent on IGF2 secretion, indicating that glutamine controls the activity of the IGF2/IGF1R autocrine loop through IGF2 up-regulation. In summary, this PhD work highlights that autocrine secretion of IGF2 is required for compensatory ß cell adaptation to ageing, pregnancy, and insulin resistance. Moreover IGF2/IGF1R autocrine loop is regulated by two feeding-related cues, GLP-1 to increase IGF-1R expression and glutamine to control IGF2 biosynthesis and secretion. -- Dans le diabète de type 2, lorsque la sécrétion d'insuline des cellules Beta du pancréas n'est plus suffisante pour compenser la résistance à l'insuline, une hyperglycémie est observée. Cette baisse de sécrétion d'insuline est Causée par la diminution de la masse de cellules Beta suite à l'augmentation du phénomène de mort cellulaire ou « apoptose ». En diabétologie, une des stratégies médicales concerne la préservation des cellules Beta du pancréas. Une des protéines intervenant dans cette fonction est GLP-1 (Glucagon-like peptide-1). GLP-1 est capable de protéger les cellules Beta contre la mort cellulaire et d'induire leur prolifération. Des études précédemment menées dans le laboratoire du Professeur Bernard Thorens ont montrées que l'activité « anti-apoptotique » de GLP-1 est le résultat l'une augmentation de l'expression du gène IGF-1R sous la dépendance de la sécrétion autocrine d'IGF2 (Insulin-Like Growth Factor). Le but de mon travail de thèse aura été d'étudier le mécanisme de la régulation de GLP-1 par IGF2 et plus précisément de déterminer le rôle physiologique d'IGF2 dans la plasticité des cellules ß ainsi que sa régulation par les nutriments. Ce manuscrit est ainsi divisé en trois chapitres : Le premier chapitre décrit la fonction d'IGF2/IGF- R1 dans la réponse des cellules Beta au glucose ainsi que dans leur capacité à proliférer. Dans ce chapitre nous avons montré l'importance du niveau d'expression d'IGFR-1 et de la sécrétion d'IGF2 dans la régulation du métabolisme du glucose. Dans un deuxième chapitre, nous étudions la boucle de régulation IGF2/IGF-R1 sur la plasticité des cellules Beta lors du vieillissement, de la grossesse ainsi que dans un modèle de souris résistantes à l'insuline. Cette étude met en évidence un dimorphisme sexuel dans le rôle d'IGF2 lors du vieillissement et lors d'un stress métabolique. Nous montrons également l'importance d'IGF2 pour l'adaptation des cellules Beta tout au long de la grossesse ou lors du phénomène de résistance à l'insuline. Dans un troisième chapitre, nous mettons en évidence la possibilité de moduler l'expression et la sécrétion d'IGF2 par les nutriments. En conclusion, ce travail de thèse aura permis de mettre en évidence l'importance d'IGF2 dans la plasticité des cellules ß, une plasticité indispensable lors du vieillissement, de la grossesse ou encore dans le cas d'une résistance à l'insuline.
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Chlorophyll determination with a portable chlorophyll meter can indicate the period of highest N demand of plants and whether sidedressing is required or not. In this sense, defining the optimal timing of N application to common bean is fundamental to increase N use efficiency, increase yields and reduce the cost of fertilization. The objectives of this study were to evaluate the efficiency of N sufficiency index (NSI) calculated based on the relative chlorophyll index (RCI) in leaves, measured with a portable chlorophyll meter, as an indicator of time of N sidedressing fertilization and to verify which NSI (90 and 95 %) value is the most appropriate to indicate the moment of N fertilization of common bean cultivar Perola. The experiment was carried out in the rainy and dry growing seasons of the agricultural year 2009/10 on a dystroferric Red Nitosol, in Botucatu, São Paulo State, Brazil. The experiment was arranged in a randomized complete block design with five treatments, consisting of N managements (M1: 200 kg ha-1 N (40 kg at sowing + 80 kg 15 days after emergence (DAE) + 80 kg 30 DAE); M2: 100 kg ha-1 N (20 kg at sowing + 40 kg 15 DAE + 40 kg 30 DAE); M3: 20 kg ha-1 N at sowing + 30 kg ha-1 when chlorophyll meter readings indicated NSI < 95 %; M4: 20 kg ha-1 N at sowing + 30 kg ha-1 N when chlorophyll meter readings indicated NSI < 90 % and, M5: control (without N application)) and four replications. The variables RCI, aboveground dry matter, total leaf N concentration, production components, grain yield, relative yield, and N use efficiency were evaluated. The RCI correlated with leaf N concentrations. By monitoring the RCI with the chlorophyll meter, the period of N sidedressing of common bean could be defined, improving N use efficiency and avoiding unnecessary N supply to common bean. The NSI 90 % of the reference area was more efficient to define the moment of N sidedressing of common bean, to increase N use efficiency.
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1. Iowa Code Section 309.22 requires the County Engineer to submit an Annual Report to the Iowa DOT by September 15 of each year. 2. Iowa DOT Administrative Rule 761, Chapter 173.3 requires the Iowa DOT to distribute a detailed set of instructions to the counties for the preparation of the report. The instructions constitute the standard requirements and forms to be followed. 3. Iowa DOT Administrative Rule 761,Chapter 178 establishes requirements for the reporting by cities and counties of project cost information to the Iowa DOT 4. Iowa DOT policy states that the report shall cover the fiscal year from July 1st of the past calendar year to June 30th of the current calendar year.
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Eukaryotic gene expression depends on a complex interplay between the transcriptional apparatus and chromatin structure. We report here a yeast model system for investigating the functional interaction between the human estrogen receptor (hER) and CTF1, a member of the CTF/NFI transcription factor family. We show that a CTF1-fusion protein and the hER transactivate a synthetic promoter in yeast in a synergistic manner. This interaction requires the proline-rich transactivation domain of CTF1. When the natural estrogen-dependent vitellogenin B1 promoter is tested in yeast, CTF1 and CTF1-fusion proteins are unable to activate transcription, and no synergy is observed between hER, which activates the B1 promoter, and these factors. Chromatin structure analysis on this promoter reveals positioned nucleosomes at -430 to -270 (+/-20 bp) and at -270 to - 100 (+/-20 bp) relative to the start site of transcription. The positions of the nucleosomes remain unchanged upon hormone-dependent transcriptional activation of the promoter, and the more proximal nucleosome appears to mask the CTF/NFI site located at - 101 to -114. We conclude that a functional interaction of hER with the estrogen response element located upstream of a basal promoter occurs in yeast despite the nucleosomal organization of this promoter, whereas the interaction of CTF1 with its target site is apparently precluded by a nucleosome.
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Crash Rates and Crash Densities on Secondary Roads in Iowa by Functional Class produced by the Iowa Department of Transportation.
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Summary In his theory On the Origin of Species by Means of Natural Selection (1859), Darwin describes evolution as a gradual change in population over time and that natural selection is a process that caused evolution. Because quantitative variation in species is partly influenced by several genes and thus heritable, association between levels of genetic variation at neutral markers and at quantitative traits and their partitioning within and among populations are important to study mechanisms that drive evolution in populations. Most studies addressing quantitative variation in plants focused on morphological and life history traits but not in traits affecting reproductive success. The aim of this thesis is to better understand how patterns of variation for neutral molecular markers and phenotypic traits drive the evolution of reproduction and defensive mechanisms in six European populations of Silene latifolia, a dioecious plant species. We found evidence for extremely high within and between population variation at six microsatellite loci and at most quantitative traits studied in plants grown under standardized conditions (morphology, life history and reproductive traits). Interestingly, there was clinal variation between age at first flowering and latitude. This pattern is likely due to natural selection since differentiation of this trait was high, heritable and probably higher than differentiation at neutral markers. Our study focused on sex specific selective pressures: mechanisms of intersexual coadaptation and defence mechanism against the seed predator Hadena bicruris. To address divergence at reproductive traits, we studied male and female population of origin effects and in particular pollen competitive ability on male post-pollination success in the study populations with within and between populations crosses. We crossed the same female plant with pollen from a male within the same population of origin and pollen from two males from two distinct populations, using a fixed tester male as a competitor. Additionally, we conducted control crosses with pollen from each male as a single donor. We analysed paternity success of each competitor with two microsatellite loci, seed set and offspring fitness. Male population of origin showed significant among-population variation for siring success at pollen competition. In vitro pollen germination rate showed heritable variation among populations and was positively correlated to siring success. Local or foreign pollen did not have a consistent advantage. Furthermore, female population of origin affected the outcome of pollen competition in some populations. There was no difference of seed set or offspring fitness in within/ between population crosses. This suggests that reproductive divergence may occur via pollen competition in Silene latifolia. The specialist seed predator Hadena bicruris may also induce divergence between populations. We tested potential constitutive and induced defence mechanisms against the specialist predator Hadena bicruris. Because fruit wall thickness is smaller in the invasive range (Northern America) were the moth is absent, this suggests that a thicker fruit wall is a potentially defensive trait against larval attack, and that relaxed selection in the absence of the seed predator has resulted in an evolutionary loss of this defence in the invasive range. Fruit wall thickness was different among three populations. Experimental exposure to moth eggs increased fruit abortion. Fruits built after attack on exposed plants did not have thicker fruit walls compared to fruits on non-exposed plants. Furthermore, fruits with thicker fruit walls were not less profitable, nor did they require longer handling time when exposed to larvae, suggesting no defensive role of fruit wall thickness. Our results show that there is high molecular and phenotypic variation in Silene latifolia and that traits potentially involved in reproductive success both for intra-specific (between sexes) and inter-specific interactions are heritable. Different selective forces may thus interact and cause differential evolution of geographically separated Silene latifolia populations in Europe, leading to the observed differentiation. Résumé Dans sa théorie de l'évolution, L'origine des espèces, ch. 4 (1859), Darwin décrit l'évolution comme un processus continu au cours du temps à l'intérieur de populations et que la sélection naturelle en est le moteur. La variation quantitative est en partie déterminée par plusieurs gènes, donc transmissible à la descendance. Associer le niveau de variation génétique à des marqueurs neutres au niveau de la variation à des traits quantitatifs, ainsi que la répartition à l'intérieur et entre les populations d'une espèce donnée de cette variation, sont importants dans la compréhension des forces évolutives. La plupart des études scientifiques sur la variation quantitative chez les plantes se sont intéressées à la morphologie et à la phénologie mais pas aux caractères impliqués dans le succès reproducteur. L'objectif de cette thèse est de mieux comprendre comment la répartition de la variation à des marqueurs neutres et des caractères quantitatifs influence l'évolution de la reproduction et des mécanismes de défense dans six populations Européennes de l'espèce dioïque Silene latifolia. Nous avons mis en évidence une grande diversité intra et inter-population à six loci microsatellites ainsi qu'à la plupart des caractères quantitatifs mesurés (morphologie, phénologie et traits reproducteurs) sur des plantes cultivées dans des conditions standardisées. Un résultat intéressant est la présence d'un cline latitudinal pour l'âge à la floraison. Ceci est probablement une conséquence de la sélection naturelle, puisque ce caractère est différencié entre les populations étudiées, héritable et que la différenciation de ce trait est supérieure à la différenciation des marqueurs neutres étudiés. Notre étude a ensuite porté plus précisément sur les pressions de sélection spécifiques aux sexes : la coadaptation entre les sexes et les mécanismes de défense contre l'insecte granivore Hadena bicruris. Afin d'évaluer la divergence sur les traits reproducteurs, nous avons étudié les effets des populations d'origine des mâles et des femelles et en particulier le succès reproducteur des mâles après pollinisation à l'aide de croisements inter et intra-population. Nous avons pollinisé la même femelle avec du pollen provenant d'un mâle de la même population ainsi qu'avec le pollen de deux mâles provenant de deux autres populations en situation de compétition avec un pollen provenant d'une population test. Des croisements contrôle ont été réalisés avec les mêmes mâles en pollinisation pure. Nous avons évalué le succès reproducteur de chaque mâle à l'aide d'analyses de paternité ainsi que la production de graines et la fitness de la descendance. L'origine du mâle avait un effet sur la paternité. Le taux de croissance in vitro du pollen est un caractère héritable et a eu un effet positif sur le succès reproducteur. De plus, l'origine de la femelle avait un effet sur le succès des mâles en compétition dans certaines populations. Nos résultats suggèrent qu'une divergence reproductive chez Silene latifolia pourrait apparaître suite à la compétition pollinique. Nous avons ensuite testé des mécanismes potentiels de défense constitutive et induite contre l'herbivore spécialiste Hadena bicruris, un papillon nocturne qui pourrait aussi jouer un rôle dans la différenciation des populations. L'épaisseur des fruits étant plus faible dans les régions où la plante est invasive (Amérique du Nord) et où l'insecte est absent, ce trait pourrait jouer un rôle défensif. Une pression de sélection plus faible causée par l'absence de l'herbivore aurait abouti à une perte de cette défense dans ces régions. Nous avons montré que l'épaisseur du fruit est variable selon les populations. L'infestation artificielle de fruit par l'insecte induit l'abscission sélective des fruits. Les fruits produits après une infestation n'étaient pas plus épais que les fruits issus de plantes non infestées. De plus, les fruits épais n'étaient pas moins nutritifs et ne causaient pas de perte de temps pour la prédation pour les larves, ce qui suggère que l'épaisseur des fruits ne joue pas un rôle défensif. Nos résultats montrent que plusieurs pressions de sélection interviennent et interagissent dans l'évolution de populations distantes, provoquant la divergence des populations Européennes de l'espèce Silene latifolia.
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The project "Quantification and qualification of ambulatory health care", financed by the Swiss National Science Foundation and covering the Cantons of Vaud and Fribourg, has two main goals: --a structural study of the elements of the ambulatory care sector. This is done through inventories of the professions concerned (physicians, public health nurses, physiotherapists, pharmacists, medical laboratories), allowing to better characterize the "offer". This inventory work includes the collect and analysis of existing statistical data as well as surveys, by questionnaires sent (from September 1980) to the different professions and by interviews. --a functional study, inspired from the US National Ambulatory Medical Care Survey and from similar studies elsewhere, in order to investigate the modes of practice of various providers, with particular regard to interprofessional collaboration (through studying referrals from the ones to the others). The first months of the project have been used for a methodological research in this regard, centered on the use of systems analysis, and for the elaboration of adequate instruments.
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Report on applying agreed-upon procedures to the Villisca Municipal Power Plant’s accounting procedures, cash and investment balances and compliance with Code of Iowa requirements for the period February 1, 2007 through December 31, 2010
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PurposeThe purpose of this study was to report the 2-year outcome of an individually tailored 'observe-and-plan' treatment regimen for neovascular age-related macular degeneration (nAMD), and to investigate its clinical value in terms of functional outcome. This regimen aimed to reduce the clinical burden (visits) by employing individually fixed injection intervals, based on the predictability of an individual's need for retreatment.MethodsThis prospective case series included 104 patients (115 eyes) with nAMD. Following three loading doses of ranibizumab, the disease recurrence interval was determined in monthly observation visits. Retreatment was applied in a series of three injections with individually fixed intervals (2 weeks shorter than the recurrence interval), combined with periodic adjustment of the intervals. The allowed injection intervals in treatment plans ranged from 1 to 3 months. If there was no recurrence at 3 months, the patient could change to monitoring alone.ResultsMean visual acuity (VA) improved by 8.7, 9.7, and 9.2 letters at months 3, 12, and 24, respectively. The mean number of injections was 7.8 and 5.8 during years 1 and 2, respectively, whereas the mean number of ophthalmic examinations was 4.0 and 2.9, respectively. The mean treatment interval (after the loading doses) was 2.0 months during year 1, and 2.2 months during year 2.ConclusionThe observe-and-plan regimen significantly improved and maintained VA over the course of 2 years. This favourable functional outcome was achieved with fewer clinic visits compared with other regimens. Therefore, this observe-and-plan regimen has the potential to alleviate the clinical burden of nAMD treatment.Eye advance online publication, 7 November 2014; doi:10.1038/eye.2014.258.
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The current state of empirical investigations refers to consciousness as an all-or-none phenomenon. However, a recent theoretical account opens up this perspective by proposing a partial level (between nil and full) of conscious perception. In the well-studied case of single-word reading, short-lived exposure can trigger incomplete word-form recognition wherein letters fall short of forming a whole word in one's conscious perception thereby hindering word-meaning access and report. Hence, the processing from incomplete to complete word-form recognition straightforwardly mirrors a transition from partial to full-blown consciousness. We therefore hypothesized that this putative functional bottleneck to consciousness (i.e. the perceptual boundary between partial and full conscious perception) would emerge at a major key hub region for word-form recognition during reading, namely the left occipito-temporal junction. We applied a real-time staircase procedure and titrated subjective reports at the threshold between partial (letters) and full (whole word) conscious perception. This experimental approach allowed us to collect trials with identical physical stimulation, yet reflecting distinct perceptual experience levels. Oscillatory brain activity was monitored with magnetoencephalography and revealed that the transition from partial-to-full word-form perception was accompanied by alpha-band (7-11 Hz) power suppression in the posterior left occipito-temporal cortex. This modulation of rhythmic activity extended anteriorly towards the visual word form area (VWFA), a region whose selectivity for word-forms in perception is highly debated. The current findings provide electrophysiological evidence for a functional bottleneck to consciousness thereby empirically instantiating a recently proposed partial perspective on consciousness. Moreover, the findings provide an entirely new outlook on the functioning of the VWFA as a late bottleneck to full-blown conscious word-form perception.
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Understanding the relative importance of historical and environmental processes in the structure and composition of communities is one of the longest quests in ecological research. Increasingly, researchers are relying on the functional and phylogenetic β-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species. The present study investigated how plant functional and phylogenetic β-diversity change along key environmental and spatial gradients in the Western Swiss Alps. Methods Using the quadratic diversity measure based on six functional traits: specific leaf area (SLA), leaf dry matter content (LDMC), plant height (H), leaf carbon content (C), leaf nitrogen content (N), and leaf carbon to nitrogen content (C/N) alongside a species-resolved phylogenetic tree, we relate variations in climate, spatial geographic, land use and soil gradients to plant functional and phylogenetic turnover in mountain communities of the Western Swiss Alps. Important findings Our study highlights two main points. First, climate and land use factors play an important role in mountain plant community turnover. Second, the overlap between plant functional and phylogenetic turnover along these gradients correlates with the low phylogenetic signal in traits, suggesting that in mountain landscapes, trait lability is likely an important factor in driving plant community assembly. Overall, we demonstrate the importance of climate and land use factors in plant functional and phylogenetic community turnover, and provide valuable complementary insights into understanding patterns of β-diversity along several ecological gradients.