355 research outputs found
Epigenetic Modifications of the PGC-1α Promoter during Exercise Induced Expression in Mice
The transcriptional coactivator, PGC-1α, is known for its role in mitochondrial biogenesis. Although originally thought to exist as a single protein isoform, recent studies have identified additional promoters which produce multiple mRNA transcripts. One of these promoters (promoter B), approximately 13.7kb upstream of the canonical PGC-1α promoter (promoter A), yields alternative transcripts present at levels much lower than the canonical PGC-1α mRNA transcript. In skeletal muscle, exercise resulted in a substantial, rapid increase of mRNA of these alternative PGC-1α transcripts. Although the β2-adrenergic receptor was identified as a signaling pathway that activates transcription from PGC-1α promoter B, it is not yet known what molecular changes occur to facilitate PGC-1α promoter B activation following exercise. We sought to determine whether epigenetic modifications were involved in this exercise response in mouse skeletal muscle. We found that DNA hydroxymethylation correlated to increased basal mRNA levels from PGC-1α promoter A, but that DNA methylation appeared to play no role in the exercise-induced activation of PGC-1α promoter B. The level of the activating histone mark H3K4me3 increased with exercise 2–4 fold across PGC- 1α promoter B, but remained unaltered past the canonical PGC-1α transcriptional start site. Together, these data show that epigenetic modifications partially explain exercise-induced changes in the skeletal muscle mRNA levels of PGC-1α isoforms
Performance of winter pasture species in different integrated crop-livestock systems in lowlands of Southern Brazil.
The introduction of winter forage species in succession to rice cropping in lowlands of Southern Brazil is an option for the productive system diversification..
Animal production in different integrated crop-livestock systems in a lowland of Southern Brazil.
To achieve higher lowland use efficiency in Brazilian Southern, a region commonly used for rice production, the livestock activity during the winter period (in succession to summer crops) is a sustainable alternative..
Implementation of different integrated crop-livestock systems in lowlands of Southern Brazil: an animal production approach.
The introduction of integrated crop-livestock systems (ICLS) is an alternative to rice monoculture in lowlands of Southern Brazil..
Braided racks, Hurwitz actions and Nichols algebras with many cubic relations
We classify Nichols algebras of irreducible Yetter-Drinfeld modules over
groups such that the underlying rack is braided and the homogeneous component
of degree three of the Nichols algebra satisfies a given inequality. This
assumption turns out to be equivalent to a factorization assumption on the
Hilbert series. Besides the known Nichols algebras we obtain a new example. Our
method is based on a combinatorial invariant of the Hurwitz orbits with respect
to the action of the braid group on three strands.Comment: v2: 35 pages, 6 tables, 14 figure
Kendomycin Cytotoxicity against Bacterial, Fungal, and Mammalian Cells Is Due to Cation Chelation
Kendomycin is a small-molecule natural product that has gained significant attention due to reported cytotoxicity against pathogenic bacteria and fungi as well as a number of cancer cell lines. Despite significant biomedical interest and attempts to reveal its mechanism of action, the cellular target of kendomycin remains disputed. Herein it is shown that kendomycin induces cellular responses indicative of cation stress comparable to the effects of established iron chelators. Furthermore, addition of excess iron and copper attenuated kendomycin cytotoxicity in bacteria, yeast, and mammalian cells. Finally, NMR analysis demonstrated a direct interaction with cations, corroborating a close link between the observed kendomycin polypharmacology across different species and modulation of iron and/or copper levels.Peer reviewe
Treatment of backscattering in a gas of interacting fermions confined to a one-dimensional harmonic atom trap
An asymptotically exact many body theory for spin polarized interacting
fermions in a one-dimensional harmonic atom trap is developed using the
bosonization method and including backward scattering. In contrast to the
Luttinger model, backscattering in the trap generates one-particle potentials
which must be diagonalized simultaneously with the two-body interactions.
Inclusion of backscattering becomes necessary because backscattering is the
dominant interaction process between confined identical one-dimensional
fermions. The bosonization method is applied to the calculation of one-particle
matrix elements at zero temperature. A detailed discussion of the validity of
the results from bosonization is given, including a comparison with direct
numerical diagonalization in fermionic Hilbert space. A model for the
interaction coefficients is developed along the lines of the Luttinger model
with only one coupling constant . With these results, particle densities,
the Wigner function, and the central pair correlation function are calculated
and displayed for large fermion numbers. It is shown how interactions modify
these quantities. The anomalous dimension of the pair correlation function in
the center of the trap is also discussed and found to be in accord with the
Luttinger model.Comment: 19 pages, 5 figures, journal-ref adde
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