365 research outputs found
Functional interactions of the AF-2 activation domain core region of the human androgen receptor with the amino-terminal domain and with the transcriptional coactivator TIF2 (transcriptional intermediary factor2)
Previous studies in yeast and mammalian cells showed a functional
interaction between the amino-terminal domain and the carboxy-terminal,
ligand-binding domain (LBD) of the human androgen receptor (AR). In the
present study, the AR subdomains involved in this in vivo interaction were
determined in more detail. Cotransfection experiments in Chinese hamster
ovary (CHO) cells and two-hybrid experiments in yeast revealed that two
regions in the NH2-terminal domain are involved in the functional
interaction with the LBD: an interacting domain at the very NH2 terminus,
located between amino acid residues 3 and 36, and a second domain,
essential for transactivation, located between residues 370 and 494.
Substitution of glutamic acid by glutamine at position 888 (E888Q) in the
AF-2 activation domain (AD) core region in the LBD, markedly decreased the
interaction with the NH2-terminal domain. This mutation neither influenced
hormone binding nor LBD homodimerization, suggesting a role of the AF-2 AD
core region in the functional interaction between the NH2-terminal domain
and the LBD. The AF-2 AD core region was also involved in the interaction
with the coactivator TIF2 (transcriptional intermediary factor 2), as the
E888Q mutation decreased the stimulatory effect of TIF2 on AR AF-2
activity. Cotransfection of TIF2 and the AR NH2-terminal domain expression
vectors did not result in synergy between both factors in the induction of
AR AF-2 activity. TIF2 highly induced AR AF-2 activity on a complex
promoter [mouse mammary tumor virus (MMTV)], but it was hardly active on a
minimal promoter (GRE-TATA). In contrast, the AR NH2-terminal domain
induced AR AF-2 activity on both promoter constructs. These data indicate
that both the AR NH2-terminal domain and the coactivator TIF2 functionally
interact, either directly or indirectly, with the AF-2 AD core region in
the AR-LBD, but the level of transcriptional response induced by TIF2
depends on the promoter context
Amino acids 3-13 and amino acids in and flanking the 23FxxLF27 motif modulate the interaction between the N-terminal and ligand-binding domain of the androgen receptor
The N-terminal domain (NTD) and the ligand-binding domain (LBD) of the
androgen receptor (AR) exhibit a ligand-dependent interaction (N/C
interaction). Amino acids 3-36 in the NTD (AR3-36) play a dominant role in
this interaction. Previously, it has been shown that a PhixxPhiPhi motif
in AR3-36, 23FxxLF27, is essential for LBD interaction. We demonstrate in
the current study that AR3-36 can be subdivided into two functionally
distinct fragments: AR3-13 and AR16-36. AR3-13 does not directly interact
with the AR LBD, but rather contributes to the transactivation function of
the AR.NTD-AR.LBD complex. AR16-36, encompassing the 23FxxLF27 motif, is
predicted to fold into a long amphipathic alpha-helix. A second
PhixxPhiPhi candidate protein interaction motif within the helical
structure, 30VREVI34, shows no affinity to the LBD. Within AR16-36, amino
acid residues in and flanking the 23FxxLF27 motif are demonstrated to
modulate N/C interaction. Substitution of Q24 and N25 by alanine residues
enhances N/C interaction. Substitution of amino acids flanking the
23FxxLF27 motif by alanines are inhibitory to LBD interaction
The Seventh Data Release of the Sloan Digital Sky Survey
This paper describes the Seventh Data Release of the Sloan Digital Sky Survey
(SDSS), marking the completion of the original goals of the SDSS and the end of
the phase known as SDSS-II. It includes 11663 deg^2 of imaging data, with most
of the roughly 2000 deg^2 increment over the previous data release lying in
regions of low Galactic latitude. The catalog contains five-band photometry for
357 million distinct objects. The survey also includes repeat photometry over
250 deg^2 along the Celestial Equator in the Southern Galactic Cap. A
coaddition of these data goes roughly two magnitudes fainter than the main
survey. The spectroscopy is now complete over a contiguous area of 7500 deg^2
in the Northern Galactic Cap, closing the gap that was present in previous data
releases. There are over 1.6 million spectra in total, including 930,000
galaxies, 120,000 quasars, and 460,000 stars. The data release includes
improved stellar photometry at low Galactic latitude. The astrometry has all
been recalibrated with the second version of the USNO CCD Astrograph Catalog
(UCAC-2), reducing the rms statistical errors at the bright end to 45
milli-arcseconds per coordinate. A systematic error in bright galaxy photometr
is less severe than previously reported for the majority of galaxies. Finally,
we describe a series of improvements to the spectroscopic reductions, including
better flat-fielding and improved wavelength calibration at the blue end,
better processing of objects with extremely strong narrow emission lines, and
an improved determination of stellar metallicities. (Abridged)Comment: 20 pages, 10 embedded figures. Accepted to ApJS after minor
correction
The Eighth Data Release of the Sloan Digital Sky Survey: First Data from SDSS-III
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with
new instrumentation and new surveys focused on Galactic structure and chemical
evolution, measurements of the baryon oscillation feature in the clustering of
galaxies and the quasar Ly alpha forest, and a radial velocity search for
planets around ~8000 stars. This paper describes the first data release of
SDSS-III (and the eighth counting from the beginning of the SDSS). The release
includes five-band imaging of roughly 5200 deg^2 in the Southern Galactic Cap,
bringing the total footprint of the SDSS imaging to 14,555 deg^2, or over a
third of the Celestial Sphere. All the imaging data have been reprocessed with
an improved sky-subtraction algorithm and a final, self-consistent photometric
recalibration and flat-field determination. This release also includes all data
from the second phase of the Sloan Extension for Galactic Understanding and
Evolution (SEGUE-2), consisting of spectroscopy of approximately 118,000 stars
at both high and low Galactic latitudes. All the more than half a million
stellar spectra obtained with the SDSS spectrograph have been reprocessed
through an improved stellar parameters pipeline, which has better determination
of metallicity for high metallicity stars.Comment: Astrophysical Journal Supplements, in press (minor updates from
submitted version
Searching for a Stochastic Background of Gravitational Waves with LIGO
The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed
the fourth science run, S4, with significantly improved interferometer
sensitivities with respect to previous runs. Using data acquired during this
science run, we place a limit on the amplitude of a stochastic background of
gravitational waves. For a frequency independent spectrum, the new limit is
. This is currently the most sensitive
result in the frequency range 51-150 Hz, with a factor of 13 improvement over
the previous LIGO result. We discuss complementarity of the new result with
other constraints on a stochastic background of gravitational waves, and we
investigate implications of the new result for different models of this
background.Comment: 37 pages, 16 figure
Erratum: “The eighth data release of the Sloan Digital Sky Survey: first data from SDSS-III” (2011, ApJS, 193, 29)
Section 3.5 of Aihara et al. (2011) described various sources of systematic error in the astrometry of the imaging data of the Sloan Digital Sky Survey (SDSS). In addition to these sources of error, there is an additional and more serious error, which introduces a large systematic shift in the astrometry over a large area around the north celestial pole. The region has irregular boundaries but in places extends as far south as declination δ ≈ 41◦. The sense of the shift is that the positions of all sources in the affected area are offset by roughly 250 mas in a northwest direction. We have updated the SDSS online documentation to reflect these errors, and to provide detailed quality information for each SDSS field
The First Data Release of the Sloan Digital Sky Survey
The Sloan Digital Sky Survey has validated and made publicly available its
First Data Release. This consists of 2099 square degrees of five-band (u, g, r,
i, z) imaging data, 186,240 spectra of galaxies, quasars, stars and calibrating
blank sky patches selected over 1360 square degrees of this area, and tables of
measured parameters from these data. The imaging data go to a depth of r ~ 22.6
and are photometrically and astrometrically calibrated to 2% rms and 100
milli-arcsec rms per coordinate, respectively. The spectra cover the range
3800--9200 A, with a resolution of 1800--2100. Further characteristics of the
data are described, as are the data products themselves.Comment: Submitted to The Astronomical Journal. 16 pages. For associated
documentation, see http://www.sdss.org/dr
The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III
The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra. \ua9 2015. The American Astronomical Society
Molecular mechanisms of cell death: recommendations of the Nomenclature Committee on Cell Death 2018.
Over the past decade, the Nomenclature Committee on Cell Death (NCCD) has formulated guidelines for the definition and interpretation of cell death from morphological, biochemical, and functional perspectives. Since the field continues to expand and novel mechanisms that orchestrate multiple cell death pathways are unveiled, we propose an updated classification of cell death subroutines focusing on mechanistic and essential (as opposed to correlative and dispensable) aspects of the process. As we provide molecularly oriented definitions of terms including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence, and mitotic catastrophe, we discuss the utility of neologisms that refer to highly specialized instances of these processes. The mission of the NCCD is to provide a widely accepted nomenclature on cell death in support of the continued development of the field
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