71 research outputs found

    Habitatvalg og beitestrategi hos overvintrende fjæreplytt (Calidris maritima)

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    Fjæreplytt (Calidris maritima) er verdens nordligste overvintrende vader og oppholder seg gruppevis i fjæresonen i Tromsøområdet gjennom vinteren. En flokk fjæreplytt ble observert å konsekvent bytte beitehabitat mellom dag og natt. Ved hjelp av radiosendere og individuelle ringmerker ble natthabitat avdekket og flokken verifisert som den samme i begge habitat. For å undersøke hva som kunne styre fuglenes valg av habitat ble mattilgang og predatoraktivitet vurdert. Næringsprøver ble samplet fra begge habitatat og potensielle byttedyr registrert for å få et bilde av næringstilgangen. Tidsbudsjett ble tatt på beitende fugl i dag- og natthabitat for å finne forskjell i beiteintensitet. I henseende å vurdere predatoraktivitet ble det tatt tidsbudsjetter på anti-predator atferd og gått sportransekt i begge habitat. Næringstilgangen ble ikke funnet å være forskjellig med hensyn på antall byttedyr. Det var kun forskjellig fordeling av type byttedyr, med flest blåskjell (Mytilus edulis) i daghabitatet og flest strandsnegl (Littorina spp.) i natthabitatet. Beiteintensiteten var høyere i natthabitatet med 83 % kontra 68 % i daghabitatet. Fuglene viste 66 % anti-predator atferd i form av flukt i daghabitatet og 40 % i natthabitatet og sportransektene ga indikasjon på større aktivitet av nattaktive predatorer som katt og mink i daghabitatet. Disse resultatene foreslår at fjæreplyttene avveier mattilgang og predatorpress når de velger beitehabitat. Predatoraktiviteten i daghabitatet kan indirekte skyldes menneskelig aktivitet som således påvirker et viktig beiteområde for den lokale bestanden av fjæreplytt i Tromsøområdet. Emneord: fjæreplytt, Calidris maritima, habitatvalg, predatorpress, avveing, anti-predator atferd, beiting, fjæreson

    Gytefeltskartlegging Nordøstarktisk hyse: Toktnummer 2022609

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    Gytekartleggingstokt for nordøstarktisk hyse ble gjennomført 8. -19. april 2022 med FF Kristine Bonnevie. Toktet startet i Bodø og ble avsluttet i Tromsø. Toktet dekket det antatte gyteområdet langs Eggakanten mellom Malangsgrunnen og Bjørnøyrenna. Kontinuerlige akustiske registringer ble gjort langs 3194 nautiske mil kurslinjer. Det ble tatt 38 stasjoner med egghåv og CTD, og 29 bunntrål. Gytende hyse ble funnet i de fleste trålhalene. De innsamlete eggene er sendt til genetisk analyse for å kunne skille torsk- og hyseegg.publishedVersio

    Dissecting the shared genetic basis of migraine and mental disorders using novel statistical tools

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    Migraine is three times more prevalent in people with bipolar disorder or depression. The relationship between schizophrenia and migraine is less certain although glutamatergic and serotonergic neurotransmission are implicated in both. A shared genetic basis to migraine and mental disorders has been suggested but previous studies have reported weak or non-significant genetic correlations and five shared risk loci. Using the largest samples to date and novel statistical tools, we aimed to determine the extent to which migraine’s polygenic architecture overlaps with bipolar disorder, depression and schizophrenia beyond genetic correlation, and to identify shared genetic loci. Summary statistics from genome-wide association studies were acquired from large-scale consortia for migraine (n cases = 59 674; n controls = 316 078), bipolar disorder (n cases = 20 352; n controls = 31 358), depression (n cases = 170 756; n controls = 328 443) and schizophrenia (n cases = 40 675, n controls = 64 643). We applied the bivariate causal mixture model to estimate the number of disorder-influencing variants shared between migraine and each mental disorder, and the conditional/conjunctional false discovery rate method to identify shared loci. Loci were functionally characterized to provide biological insights. Univariate MiXeR analysis revealed that migraine was substantially less polygenic (2.8 K disorder-influencing variants) compared to mental disorders (8100–12 300 disorder-influencing variants). Bivariate analysis estimated that 800 (SD = 300), 2100 (SD = 100) and 2300 (SD = 300) variants were shared between bipolar disorder, depression and schizophrenia, respectively. There was also extensive overlap with intelligence (1800, SD = 300) and educational attainment (2100, SD = 300) but not height (1000, SD = 100). We next identified 14 loci jointly associated with migraine and depression and 36 loci jointly associated with migraine and schizophrenia, with evidence of consistent genetic effects in independent samples. No loci were associated with migraine and bipolar disorder. Functional annotation mapped 37 and 298 genes to migraine and each of depression and schizophrenia, respectively, including several novel putative migraine genes such as L3MBTL2, CACNB2 and SLC9B1. Gene-set analysis identified several putative gene sets enriched with mapped genes including transmembrane transport in migraine and schizophrenia. Most migraine-influencing variants were predicted to influence depression and schizophrenia, although a minority of mental disorder-influencing variants were shared with migraine due to the difference in polygenicity. Similar overlap with other brain-related phenotypes suggests this represents a pool of ‘pleiotropic’ variants that influence vulnerability to diverse brain-related disorders and traits. We also identified specific loci shared between migraine and each of depression and schizophrenia, implicating shared molecular mechanisms and highlighting candidate migraine genes for experimental validation

    Loss-of-Function Genomic Variants Highlight Potential Therapeutic Targets for Cardiovascular Disease

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    Pharmaceutical drugs targeting dyslipidemia and cardiovascular disease (CVD) may increase the risk of fatty liver disease and other metabolic disorders. To identify potential novel CVD drug targets without these adverse effects, we perform genome-wide analyses of participants in the HUNT Study in Norway (n = 69,479) to search for protein-altering variants with beneficial impact on quantitative blood traits related to cardiovascular disease, but without detrimental impact on liver function. We identify 76 (11 previously unreported) presumed causal protein-altering variants associated with one or more CVD- or liver-related blood traits. Nine of the variants are predicted to result in loss-of-function of the protein. This includes ZNF529:p.K405X, which is associated with decreased low-density-lipoprotein (LDL) cholesterol (P = 1.3 × 10−8) without being associated with liver enzymes or non-fasting blood glucose. Silencing of ZNF529 in human hepatoma cells results in upregulation of LDL receptor and increased LDL uptake in the cells. This suggests that inhibition of ZNF529 or its gene product should be prioritized as a novel candidate drug target for treating dyslipidemia and associated CVD

    A SUMO-regulated activation function controls synergy of c-Myb through a repressor–activator switch leading to differential p300 recruitment

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    Synergy between transcription factors operating together on complex promoters is a key aspect of gene activation. The ability of specific factors to synergize is restricted by sumoylation (synergy control, SC). Focusing on the haematopoietic transcription factor c-Myb, we found evidence for a strong SC linked to SUMO-conjugation in its negative regulatory domain (NRD), while AMV v-Myb has escaped this control. Mechanistic studies revealed a SUMO-dependent switch in the function of NRD. When NRD is sumoylated, the activity of c-Myb is reduced. When sumoylation is abolished, NRD switches into being activating, providing the factor with a second activation function (AF). Thus, c-Myb harbours two AFs, one that is constitutively active and one in the NRD being SUMO-regulated (SRAF). This double AF augments c-Myb synergy at compound natural promoters. A similar SUMO-dependent switch was observed in the regulatory domains of Sp3 and p53. We show that the change in synergy behaviour correlates with a SUMO-dependent differential recruitment of p300 and a corresponding local change in histone H3 and H4 acetylation. We therefore propose a general model for SUMO-mediated SC, where SUMO controls synergy by determining the number and strength of AFs associated with a promoter leading to differential chromatin signatures

    GWAS of thyroid stimulating hormone highlights pleiotropic effects and inverse association with thyroid cancer

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    Correction: Volume12, Issue1 Article Number7354 DOI10.1038/s41467-021-27675-w PublishedDEC 16 2021Thyroid stimulating hormone (TSH) is critical for normal development and metabolism. To better understand the genetic contribution to TSH levels, we conduct a GWAS meta-analysis at 22.4 million genetic markers in up to 119,715 individuals and identify 74 genome-wide significant loci for TSH, of which 28 are previously unreported. Functional experiments show that the thyroglobulin protein-altering variants P118L and G67S impact thyroglobulin secretion. Phenome-wide association analysis in the UK Biobank demonstrates the pleiotropic effects of TSH-associated variants and a polygenic score for higher TSH levels is associated with a reduced risk of thyroid cancer in the UK Biobank and three other independent studies. Two-sample Mendelian randomization using TSH index variants as instrumental variables suggests a protective effect of higher TSH levels (indicating lower thyroid function) on risk of thyroid cancer and goiter. Our findings highlight the pleiotropic effects of TSH-associated variants on thyroid function and growth of malignant and benign thyroid tumors. Thyroid stimulating hormone (TSH) is critical for normal development and metabolism. Here, the authors conduct a GWAS and suggest protective effect of higher TSH on risk of thyroid cancer and goitre.Peer reviewe

    Author Correction:GWAS of thyroid stimulating hormone highlights the pleiotropic effects and inverse association with thyroid cancer

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    The original version of this article contained an error in the results, in the second paragraph of the subsection entitled “Fine-mapping for potentially causal variants among TSH loci”, in which effect sizes for two variants were incorrectly reported

    Deciphering osteoarthritis genetics across 826,690 individuals from 9 populations

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    Osteoarthritis affects over 300 million people worldwide. Here, we conduct a genome-wide association study meta-analysis across 826,690 individuals (177,517 with osteoarthritis) and identify 100 independently associated risk variants across 11 osteoarthritis phenotypes, 52 of which have not been associated with the disease before. We report thumb and spine osteoarthritis risk variants and identify differences in genetic effects between weight-bearing and non-weight-bearing joints. We identify sex-specific and early age-at-onset osteoarthritis risk loci. We integrate functional genomics data from primary patient tissues (including articular cartilage, subchondral bone, and osteophytic cartilage) and identify high-confidence effector genes. We provide evidence for genetic correlation with phenotypes related to pain, the main disease symptom, and identify likely causal genes linked to neuronal processes. Our results provide insights into key molecular players in disease processes and highlight attractive drug targets to accelerate translation
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