Search results for "nucleus"
showing 10 items of 1803 documents
Expanded CCUG repeat RNA expression in Drosophila heart and muscle trigger Myotonic Dystrophy type 1-like phenotypes and activate autophagocytosis ge…
2016
AbstractMyotonic dystrophies (DM1–2) are neuromuscular genetic disorders caused by the pathological expansion of untranslated microsatellites. DM1 and DM2, are caused by expanded CTG repeats in the 3′UTR of the DMPK gene and CCTG repeats in the first intron of the CNBP gene, respectively. Mutant RNAs containing expanded repeats are retained in the cell nucleus, where they sequester nuclear factors and cause alterations in RNA metabolism. However, for unknown reasons, DM1 is more severe than DM2. To study the differences and similarities in the pathogenesis of DM1 and DM2, we generated model flies by expressing pure expanded CUG ([250]×) or CCUG ([1100]×) repeats, respectively, and compared …
Sense and Antisense DMPK RNA Foci Accumulate in DM1 Tissues during Development.
2015
International audience; Myotonic dystrophy type 1 (DM1) is caused by an unstable expanded CTG repeat located within the DMPK gene 3'UTR. The nature, severity and age at onset of DM1 symptoms are very variable in patients. Different forms of the disease are described, among which the congenital form (CDM) is the most severe. Molecular mechanisms of DM1 are well characterized for the adult form and involve accumulation of mutant DMPK RNA forming foci in the nucleus. These RNA foci sequester proteins from the MBNL family and deregulate CELF proteins. These proteins are involved in many cellular mechanisms such as alternative splicing, transcriptional, translational and post-translational regul…
Molecular Effects of the CTG Repeats in Mutant Dystrophia Myotonica Protein Kinase Gene
2008
Myotonic Dystrophy type 1 (DM1) is a multi-system disorder characterized by muscle wasting, myotonia, cardiac conduction defects, cataracts, and neuropsychological dysfunction. DM1 is caused by expansion of a CTG repeat in the 3 untranslated region (UTR) of the Dystrophia Myotonica Protein Kinase (DMPK) gene. A body of work demonstrates that DMPK mRNAs containing abnormally expanded CUG repeats are toxic to several cell types. A core mechanism underlying symptoms of DM1 is that mutant DMPK RNA interferes with the developmentally regulated alternative splicing of defined pre-mRNAs. Expanded CUG repeats fold into ds(CUG) hairpins that sequester nuclear proteins including human Muscleblind-lik…
Neutrino-nucleus scattering off 136Xe
2015
Background: Theoretical estimates of the cross sections for the neutrino-nucleus scattering off relevant nuclei for supernova neutrinos are essential for many applications in neutrino physics and astrophysics. The double- β-decaying nucleus 136Xe nucleus is used by the EXO Collaboration in the search for neutrinoless double-β decay. A ton-scale experiment based on 136Xe could also be used for studies of supernova neutrinos and/or solar neutrinos. Purpose: The purpose of the present work is, thus, to perform a study of the charged-current and neutral-current nuclear responses to supernova neutrinos for 136Xe. Method: The cross sections are computed by using the well-established framework for…
Nuclear structure and neutrino-nucleus reactions at supernova energies
2015
Supernova-(anti-)neutrino–nucleus scattering is discussed with reference to neutral-current (NC) and charged-current (CC) processes in heavy stable nuclei. The Donnelly-Walecka method with the associated multipole expansion of the nucleonic current has been adopted as the basic framework in deriving the neutrino-nucleus scattering cross sections. The needed nuclear wave functions are computed by using the quasiparticle random-phase approximation (QRPA) for the even-even target nuclei in the NC processes and the proton-neutron QRPA (pnQRPA) has been used to compute the CC processes for the mentioned nuclei. The wave functions of the stable odd-mass target nuclei have been obtained by the use…
Spectroscopy of At 201 including the observation of a shears band and the 29/2 + isomeric state
2015
The excited states of 201At were studied and an isomeric 29/2 + state [T1/2 = 3.39(9) μs] was identified by using a fusion-evaporation reaction, a gas-filled recoil separator, and recoil gating techniques. The 29/2 + state is suggested to originate from the π(h9/2) ⊗ |200Po;11− configuration, and it decays through the 269- and 339-keV E2- and E3-type transitions, respectively. Moreover, a cascade of magnetic dipole transitions that is suggested to originate from a shears band was observed by using recoil-gated γ − γ (−γ ) coincidence techniques. peerReviewed
The beta-delayed proton and gamma decay of 27P for nuclear astrophysics
2013
The creation site of 26Al is still under debate. It is thought to be produced in hydrogen burning and in explosive helium burning in novae and supernovae, and possibly also in the H-burning in outer shells of red giant stars. Also, the reactions for its creation or destruction are not completely known. When 26Al is created in novae, the reaction chain is: 24Mg(p, γ) 25Al(β +ν) 25Mg(p, γ) 26Al, but this chain can be by-passed by another chain, 25Al(p, γ) 26Si(p, γ) 27P and it can also be destroyed directly. The reaction 26mAl(p, γ) 27Si∗ is another avenue to bypass the production of 26Al and it is dominated by resonant capture. We find and study these resonances by an indirect method, throug…
Amygdaloid projections to the ventral striatum in mice: direct and indirect chemosensory inputs to the brain reward system
2011
Rodents constitute good models for studying the neural basis of socio-sexual behaviour. Recent findings in mice have revealed the molecular identity of the some pheromonal molecules triggering intersexual attraction. However, the neural pathways mediating this basic socio-sexual behaviour remain elusive. Since previous work indicates that the dopaminergic tegmento-striatal pathway is not involved in pheromone reward, the present report explores alternative pathways linking the vomeronasal system with the tegmento-striatal system (the limbic basal ganglia) by means of tract-tracing experiments studying direct and indirect projections from the chemosensory amygdala to the ventral striato-pall…
Identical transitions in the strongly deformed 99Sr and 100Sr
2001
The decay of the very neutron-rich nucleus 100 Rb has been studied by γ spectroscopy of online mass-separated samples. Schemes for β decay to 100 Sr and β n decay to 99 Sr are presented. New sets of transitions in 99 Sr and 100 Sr with identical energies are observed. All identical bands so far observed in neutron-rich Sr isotopes obey a simple energy rule valid for even-even, odd-even, and odd-odd bands. peerReviewed
Direct measurement of the mass difference of $^{72}$As-$^{72}$Ge rules out $^{72}$As as a promising $\beta$-decay candidate to determine the neutrino…
2021
We report the first direct determination of the ground-state to ground-state electron-capture $Q$-value for the $^{72}$As to $^{72}$Ge decay by measuring their atomic mass difference utilizing the double Penning trap mass spectrometer, JYFLTRAP. The $Q$-value was measured to be 4343.596(75)~keV, which is more than a 50-fold improvement in precision compared to the value in the most recent Atomic Mass Evaluation 2020. Furthermore, the new $Q$-value was found to be 12.4(40)~keV (3.1 $\sigma$) lower. With the significant reduction of the uncertainty of the ground-state to ground-state $Q$-value value combined with the level scheme of $^{72}$Ge from $\gamma$-ray spectroscopy, we confirm that th…