64 research outputs found

    A novel form of JARID2 is required for differentiation in lineage-committed cells

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    Polycomb repressive complex‐2 (PRC 2) is a group of proteins that play an important role during development and in cell differentiation. PRC 2 is a histone‐modifying complex that catalyses methylation of lysine 27 of histone H3 (H3K27me3) at differentiation genes leading to their transcriptional repression. JARID 2 is a co‐factor of PRC 2 and is important for targeting PRC 2 to chromatin. Here, we show that, unlike in embryonic stem cells, in lineage‐committed human cells, including human epidermal keratinocytes, JARID 2 predominantly exists as a novel low molecular weight form, which lacks the N‐terminal PRC 2‐interacting domain (ΔN‐JARID 2). We show that ΔN‐JARID 2 is a cleaved product of full‐length JARID 2 spanning the C‐terminal conserved jumonji domains. JARID 2 knockout in keratinocytes results in up‐regulation of cell cycle genes and repression of many epidermal differentiation genes. Surprisingly, repression of epidermal differentiation genes in JARID 2‐null keratinocytes can be rescued by expression of ΔN‐JARID 2 suggesting that, in contrast to PRC 2, ΔN‐JARID 2 promotes activation of differentiation genes. We propose that a switch from expression of full‐length JARID 2 to ΔN‐JARID 2 is important for the up‐regulation differentiation genes

    First observations of separated atmospheric nu_mu and bar{nu-mu} events in the MINOS detector

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    The complete 5.4 kton MINOS far detector has been taking data since the beginning of August 2003 at a depth of 2070 meters water-equivalent in the Soudan mine, Minnesota. This paper presents the first MINOS observations of nu” and [overline nu ]” charged-current atmospheric neutrino interactions based on an exposure of 418 days. The ratio of upward- to downward-going events in the data is compared to the Monte Carlo expectation in the absence of neutrino oscillations, giving Rup/downdata/Rup/downMC=0.62-0.14+0.19(stat.)±0.02(sys.). An extended maximum likelihood analysis of the observed L/E distributions excludes the null hypothesis of no neutrino oscillations at the 98% confidence level. Using the curvature of the observed muons in the 1.3 T MINOS magnetic field nu” and [overline nu ]” interactions are separated. The ratio of [overline nu ]” to nu” events in the data is compared to the Monte Carlo expectation assuming neutrinos and antineutrinos oscillate in the same manner, giving R[overline nu ][sub mu]/nu[sub mu]data/R[overline nu ][sub mu]/nu[sub mu]MC=0.96-0.27+0.38(stat.)±0.15(sys.), where the errors are the statistical and systematic uncertainties. Although the statistics are limited, this is the first direct observation of atmospheric neutrino interactions separately for nu” and [overline nu ]”

    No association of vitamin D metabolism-related polymorphisms and melanoma risk as well as melanoma prognosis: a case–control study

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    Melanoma is one of the most aggressive human cancers. The vitamin D system contributes to the pathogenesis and prognosis of malignancies including cutaneous melanoma. An expression of the vitamin D receptor (VDR) and an anti-proliferative effect of vitamin D in melanocytes and melanoma cells have been shown in vitro. Studies examining associations of polymorphisms in genes coding for vitamin D metabolism-related proteins (1α-hydroxylase [CYP27B1], 1,25(OH)2D-24hydroxylase [CYP24A1], vitamin D-binding protein [VDBP]) and cancer risk are scarce, especially with respect to melanoma. Mainly VDR polymorphisms regarding melanoma risk and prognosis were examined although other vitamin D metabolism-related genes may also be crucial. In our hospital-based case–control study including 305 melanoma patients and 370 healthy controls single nucleotide polymorphisms in the genes CYP27B1 (rs4646536), CYP24A1 (rs927650), VDBP (rs1155563, rs7041), and VDR (rs757343, rs731236, rs2107301, rs7975232) were analyzed for their association with melanoma risk and prognosis. Except VDR rs731236 and VDR rs2107301, the other six polymorphisms have not been analyzed regarding melanoma before. To further improve the prevention as well as the treatment of melanoma, it is important to identify further genetic markers for melanoma risk as well as prognosis in addition to the crude phenotypic, demographic, and environmental markers used in the clinic today. A panel of genetic risk markers could help to better identify individuals at risk for melanoma development or worse prognosis. We, however, found that none of the polymorphisms tested was associated with melanoma risk as well as prognosis in logistic and linear regression models in our study population

    Barbarians at the British Museum: Anglo-Saxon Art, Race and Religion

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    A critical historiographical overview of art historical approaches to early medieval material culture, with a focus on the British Museum collections and their connections to religion

    Observation of Muon Neutrino Disappearance with the MINOS Detectors in the NuMI Neutrino Beam

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    This Letter reports results from the MINOS experiment based on its initial exposure to neutrinos from the Fermilab NuMI beam. The rates and energy spectra of charged current ΜΌ interactions are compared in two detectors located along the beam axis at distances of 1 and 735 km. With 1.27×1020 120 GeV protons incident on the NuMI target, 215 events with energies below 30 GeV are observed at the Far Detector, compared to an expectation of 336±14 events. The data are consistent with ΜΌ disappearance via oscillations with |Δm322|=2.74-0.26+0.44×10-3  eV2 and sin⁥2(2Ξ23)>0.87 (68% C.L.)

    Helicoverpa armigera (Hubner): can wheat stubble protect cotton plants against attack?

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    When investigating strategies for Helicoverpa armigera (Hubner) control, it is important to understand oviposition behaviour. Cotton (Gossypium hirsutum) was sown into standing wheat (Triticum astivum L.) stubble in a closed arena to investigate the effect of stubble on H. armigera moth behaviour and oviposition. Infrared cameras were used to track moths and determine whether stubble acted as a physical barrier or provided camouflage to cotton plants, thereby reducing oviposition. Searching activity was observed to peak shortly before dawn (03:00 and 04:00 h) and remained high until just after dawn (4 h window). Moths spent more time resting on cotton plants than spiralling above them, and the least time flying across the arena. While female moths spent more time searching for cotton plants growing in wheat stubble, the difference in oviposition was not significant. As similar numbers of eggs were laid on cotton plants with stubble (3.5/plant SE +/- 0.87) and without stubble (2.5/plant SE +/- 0.91), wheat stubble does not appear to provide camouflage to cotton plants. There was no significant difference in the location of eggs deposited on cotton plants with and without stubble, although more eggs were laid on the tops of cotton leaves in wheat stubble. As the spatial and temporal distribution of eggs laid on the cotton plant is a crucial component of population stability, eggs laid on the upper side of leaves on cotton plants may be more prone to fatalities caused by environmental factors such as wind and rain. Therefore, although stubble did not influence the number of eggs laid, it did affect their distribution on the plant, which may result in increased mortality of eggs on cotton plants sown into standing wheat stubble

    Imprinted X chromosome inactivation: evolution of mechanisms in distantly related mammals

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