ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2013-03-22
    Description: Metal-responsive transcription factor 1 (MTF-1) regulates a variety of genes involving in metal homeostasis and oxidative stress. We have shown that MTF-1 can be conjugated by small ubiquitin-like modifier (SUMO) and forms complexes with cellular factor(s) in a SUMO-interacting motif (SIM)-dependent manner. To investigate whether the interaction of MTF-1 and its SUMO conjugate occurs, we expressed and isolated MTF-1 and sumoylated MTF-1 (S-MTF-1) for functional studies. Various conditions were examined to optimize the expressions of MTF-1 and S-MTF-1. Results from affinity column chromatography demonstrated that the unmodified MTF-1 consistently co-eluted with the S-MTF-1. Mutations at the SIM did not reduce the level of MTF-1 sumoylation but the sumoylated product can then be purified to homogeneity. The presence of MTF-1 cross-interaction was further supported by in vitro pull-down assays. The ability of the purified proteins in binding metal-responsive element (MRE) was assessed with electrophoretic mobility shift assay. Noticeably, MTF-1 required the presence of cell extracts to render the binding activity. However, S-MTF-1 binds MRE in void of other cellular factors. The same characteristic was found for MTF-1 with SUMO fusion at the carboxyl terminus. These results indicate that the presence of SUMO moiety allows the protein to interact directly with MRE.
    Print ISSN: 0021-924X
    Electronic ISSN: 1756-2651
    Topics: Biology , Chemistry and Pharmacology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2015-05-29
    Description: Irradiation of samples of pure solid methane at 3 K with far-ultraviolet light from a synchrotron yielded products CH 3 , C 2 H 2 , C 2 H 4 and C 2 H 6 that were quantitatively identified through their infrared absorption spectra. The greatest wavelengths at which products CH 3 , C 2 H 4 , C 2 H 6 and C 2 H 2 were generated were 140, 140, 175 and 190 nm, respectively. Cassini spacecraft has observed the condensed methane on Titan. The observation demonstrates the existence of pure condensed methane in astro-environments. Information about the dissociation of CH 4 at a low temperature with photons of varied energy has implications for astrophysical environments.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2013-09-25
    Description: Spinal muscular atrophy (SMA) is caused by mutations of the survival motor neuron 1 ( SMN1 ) gene, retention of the survival motor neuron 2 ( SMN2 ) gene and insufficient expression of full-length survival motor neuron (SMN) protein. Quinazolines increase SMN2 promoter activity and inhibit the ribonucleic acid scavenger enzyme DcpS. The quinazoline derivative RG3039 has advanced to early phase clinical trials. In preparation for efficacy studies in SMA patients, we investigated the effects of RG3039 in severe SMA mice. Here, we show that RG3039 distributed to central nervous system tissues where it robustly inhibited DcpS enzyme activity, but minimally activated SMN expression or the assembly of small nuclear ribonucleoproteins. Nonetheless, treated SMA mice showed a dose-dependent increase in survival, weight and motor function. This was associated with improved motor neuron somal and neuromuscular junction synaptic innervation and function and increased muscle size. RG3039 also enhanced survival of conditional SMA mice in which SMN had been genetically restored to motor neurons. As this systemically delivered drug may have therapeutic benefits that extend beyond motor neurons, it could act additively with SMN-restoring therapies delivered directly to the central nervous system such as antisense oligonucleotides or gene therapy.
    Print ISSN: 0964-6906
    Electronic ISSN: 1460-2083
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2013-06-08
    Description: The introduction of next generation sequencing methods in genome studies has made it possible to shift research from a gene-centric approach to a genome wide view. Although methods and tools to detect single nucleotide polymorphisms are becoming more mature, methods to identify and visualize structural variation (SV) are still in their infancy. Most genome browsers can only compare a given sequence to a reference genome; therefore, direct comparison of multiple individuals still remains a challenge. Therefore, the implementation of efficient approaches to explore and visualize SVs and directly compare two or more individuals is desirable. In this article, we present a visualization approach that uses space-filling Hilbert curves to explore SVs based on both read-depth and pair-end information. An interactive open-source Java application, called Meander , implements the proposed methodology, and its functionality is demonstrated using two cases. With Meander , users can explore variations at different levels of resolution and simultaneously compare up to four different individuals against a common reference. The application was developed using Java version 1.6 and Processing.org and can be run on any platform. It can be found at http://homes.esat.kuleuven.be/~bioiuser/meander .
    Keywords: Computational Methods, Genomics
    Print ISSN: 0305-1048
    Electronic ISSN: 1362-4962
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2015-04-28
    Description: Several observations of transition discs show lopsided dust distributions. A potential explanation is the formation of a large-scale vortex acting as a dust-trap at the edge of a gap opened by a giant planet. Numerical models of gap-edge vortices have so far employed locally isothermal discs in which the temperature profile is held fixed, but the theory of this vortex-forming or ‘Rossby wave’ instability was originally developed for adiabatic discs. We generalize the study of planetary gap stability to non-isothermal discs using customized numerical simulations of disc–planet systems where the planet opens an unstable gap. We include in the energy equation a simple cooling function with cooling time-scale $t_{\rm c}=\beta \Omega _{\rm k}^{-1}$ , where k is the Keplerian frequency, and examine the effect of β on the stability of gap edges and vortex lifetimes. We find increasing β lowers the growth rate of non-axisymmetric perturbations, and the dominant azimuthal wavenumber m decreases. We find a quasi-steady state consisting of one large-scale, overdense vortex circulating the outer gap edge, typically lasting O (10 3 ) orbits. We find vortex lifetimes generally increase with the cooling time-scale t c up to an optimal value of t c  ~ 10 orbits, beyond which vortex lifetimes decrease. This non-monotonic dependence is qualitatively consistent with recent studies using strictly isothermal discs that vary the disc aspect ratio. The lifetime and observability of gap-edge vortices in protoplanetary discs is therefore dependent on disc thermodynamics.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2016-01-02
    Description: To understand the interactions between active galactic nuclei (AGNs) and star formation during the evolution of galaxies, we investigate 142 galaxies detected in both X-ray and 70 μm observations in the COSMOS (Cosmic Evolution Survey) field. All of our data are obtained from the archive X-ray point-source catalogues from Chandra and XMM–Newton observations, and the far-infrared 70 μm point-source catalogue from Spitzer-MIPS observations. Although the IRAC [3.6 μm]–[4.5 μm] versus [5.8 μm]–[8.0 μm] colours of our sample indicate that only ~63 per cent of our sources would be classified as AGNs, the ratio of the rest-frame 2–10 keV luminosity to the total infrared luminosity (8–1000 μm) shows that the entire sample has comparatively higher X-ray luminosity than that expected from pure star-forming galaxies, suggesting the presence of an AGN in all of our sources. From an analysis of the X-ray hardness ratio, we find that sources with both 70 μm and X-ray detection tend to have a higher hardness ratio relative to the whole X-ray-selected source population, suggesting the presence of more X-ray absorption in the 70 μm detected sources. In addition, we find that the observed far-infrared colours of 70 μm detected sources with and without X-ray emission are similar, suggesting the far-infrared emission could be mainly powered by star formation.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2015-05-20
    Description: The E3 ubiquitin ligase HUWE1/Mule/ARF-BP1 plays an important role in integrating/coordinating diverse cellular processes such as DNA damage repair and apoptosis. A previous study has shown that HUWE1 is required for the early step of DNA damage-induced apoptosis, by targeting MCL-1 for proteasomal degradation. However, HUWE1 is subsequently inactivated, promoting cell survival and the subsequent DNA damage repair process. The mechanism underlying its regulation during this process remains largely undefined. Here, we show that the Cullin4B-RING E3 ligase (CRL4B) is required for proteasomal degradation of HUWE1 in response to DNA damage. CUL4B is activated in a NEDD8-dependent manner, and ubiquitinates HUWE1 in vitro and in vivo . The depletion of CUL4B stabilizes HUWE1, which in turn accelerates the degradation of MCL-1, leading to increased induction of apoptosis. Accordingly, cells deficient in CUL4B showed increased sensitivity to DNA damage reagents. More importantly, upon CUL4B depletion, these phenotypes can be rescued through simultaneous depletion of HUWE1 , consistent with the role of CUL4B in regulating HUWE1. Collectively, these results identify CRL4B as an essential E3 ligase in targeting the proteasomal degradation of HUWE1 in response to DNA damage, and provide a potential strategy for cancer therapy by targeting HUWE1 and the CUL4B E3 ligase.
    Print ISSN: 0305-1048
    Electronic ISSN: 1362-4962
    Topics: Biology
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2015-07-08
    Description: Bounded, semi-infinite Hankel matrices of finite rank over the space 2 of square-summable sequences occur frequently in classical analysis and engineering applications. The notion of finite rank often appears under different contexts and the literature is diverse. The first part of this paper reviews some elegant, classical criteria and establishes connections among the various characterizations of finite rank in terms of rational functions, recursion, matrix factorizations and sinusoidal signals. All criteria require 2 d parameters, though with different meanings, for a matrix of rank d . The Vandermonde factorization, in particular, permits immediately a singular-value preserving, finite-dimensional representation of the original semi-infinite Hankel matrix and, hence, makes it possible to retrieve the nonzero singular values of the semi-infinite Hankel matrix. The second part of this paper proposes using the LDL* decomposition of a specially constructed sample matrix to find the unitarily equivalent finite-dimensional representation. This approach enjoys several advantages, including the ease of computation by avoiding infinite-dimensional vectors, the ability to reveal rank deficiency and the established pivoting strategy for stability. No error analysis is given, but several computational issues are discussed.
    Print ISSN: 0272-4979
    Electronic ISSN: 1464-3642
    Topics: Mathematics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2015-06-12
    Description: Irradiation of samples of pure solid methane at 3 K with far-ultraviolet light from a synchrotron yielded products CH 3 , C 2 H 2 , C 2 H 4 and C 2 H 6 that were quantitatively identified through their infrared absorption spectra. The greatest wavelengths at which products CH 3 , C 2 H 4 , C 2 H 6 and C 2 H 2 were generated were 140, 140, 175 and 190 nm, respectively. Cassini spacecraft has observed the condensed methane on Titan. The observation demonstrates the existence of pure condensed methane in astro-environments. Information about the dissociation of CH 4 at a low temperature with photons of varied energy has implications for astrophysical environments.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2012-09-28
    Description: A number of mouse models for spinal muscular atrophy (SMA) have been genetically engineered to recapitulate the severity of human SMA by using a targeted null mutation at the mouse Smn1 locus coupled with the transgenic addition of varying copy numbers of human SMN2 genes. Although this approach has been useful in modeling severe SMA and very mild SMA, a mouse model of the intermediate form of the disease would provide an additional research tool amenable for drug discovery. In addition, many of the previously engineered SMA strains are multi-allelic by design, containing a combination of transgenes and targeted mutations in the homozygous state, making further genetic manipulation difficult. A new genetic engineering approach was developed whereby variable numbers of SMN2 sequences were incorporated directly into the murine Smn1 locus. Using combinations of these alleles, we generated an allelic series of SMA mouse strains harboring no, one, two, three, four, five, six or eight copies of SMN2. We report here the characterization of SMA mutants in this series that displayed a range in disease severity from embryonic lethal to viable with mild neuromuscular deficits.
    Print ISSN: 0964-6906
    Electronic ISSN: 1460-2083
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...