696 research outputs found
Massive Molecular Parallel Evolution of the HSP90AA1 Gene between High-elevation Anurans
HSP90AA1 is part of the heat shock protein 90 gene family and has important functions against heat stress. We report a case of molecular level parallel evolution of the HSP90AA1 gene in high elevation amphibians. IISP90AA1 gene sequences of four high-elevation anurans, Bufo gargarizans, Nanorana parkeri, Rana kukunoris, and Scutiger boulengeri, were compared along with five of their low-elevation relatives. A total of 16 amino-acid sites were identified as parallel evolution between N parkeri and R. kukunoris. We generated both model based (Zhang and Kumar's test) and empirical data based (parallel/divergence plotting) null distributions for non-parallel evolution, and both methods clearly determined that the observed number of parallel substitutions were significantly more than the null expectation. Furthermore, on the HSP90AA1 gene tree, N. parkeri and R. kukunoris formed a strongly supported Glade that was away from their respective relatives. This study provides a clear case of molecular parallel evolution, which may have significant implications in understanding the genetic mechanisms of high-elevation adaptation
Impact of Inorganically Bound Sulfur on Late Shale Gas Generation
Nonisothermal,
confined pyrolysis was applied to a mature shale
sample from the Ordovician Salgan Formation in Tarim Basin, northwest
China. Experiments were conducted using gold-tubes with added water
at a very slow heating rate (2 Ā°C/h) and end temperatures between
336 and 600 Ā°C. To investigate the influence of inorganically
bound sulfur on the generation of gases and to consider the geological
occurrence of sulfur-containing minerals, such as prevalent pyrite
in shales, the experiments were carried out with and without admixtures
of MgSO<sub>4</sub>, CaSO<sub>4</sub>, and pyrite. High amounts of
methane along with lower amounts of wet gases were formed from highly
mature shale without minerals added, demonstrating a huge late gas
generation potential at post peak-oil window maturities. In the experiments
with added sulfates and pyrite, all organic gases were consumed in
varying proportions, resulting in different chemical and stable carbon
isotopic compositions. Pyrite treatment affects wet gas (C<sub>2</sub>āC<sub>5</sub>) evolution directly, but it affects methane
(C<sub>1</sub>) evolution indirectly. In contrast, sulfate treatments
affect C<sub>1</sub>āC<sub>5</sub> evolution directly. The
cumulative yield ratio of CO<sub>2</sub>/H<sub>2</sub>S indicates
that pyrite impacts on the hydrocarbon gas generation through low
valence sulfur such as S<sup>0</sup> or others, which are associated
with H<sub>2</sub>S generation. In the pyrite series, the smooth increase
in ethane yield at temperatures exceeding 504 Ā°C, together with
a concomitant stable carbon isotope reversal, demonstrates a new origin
for ethane at high temperatures. The isotopic reversal may come from
reactions between water and solid kerogen/coke/pyrobitumen. Isotopic
reversal of ethane occurs only in the control and pyrite series but
not in the sulfate treatments. This provides evidence that anoxic
conditions are required. Thus, one can expect to encounter isotopic
reversals in high maturity, unconventional gas shale environments
in the presence of pyrite
Comparative transcriptome analysis reveals resistance-related genes and pathways in Musa acuminata banana 'Guijiao 9' in response to Fusarium wilt.
Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc), is one of the most devastating diseases in bananas resulting in significant loss of Cavendish bananas production worldwide. Here we show the agronomic traits and the resistance of 'Guijiao 9' in the field trials from 2012 to 2017. And then we dissect and compare the transcriptome response from these two cultivars (cv. 'Guijiao 9' and cv. Williams) in an attempt to understand the molecular basis that contribute to the enhanced Foc tropical race 4 (Foc-TR4) resistance. 'Guijiao 9' is a Cavendish cultivar with strong resistance to Foc-TR4, which was reflected in a lower disease severity and incidence in glasshouse and field trails, when compared to the susceptible cultivar Williams. Gene expression profiles of 'Guijiao 9' and Williams were captured by performing RNA-Seq analysis on 16 biological samples collected over a six day period post inoculation with Foc-TR4. Transcriptional reprogramming in response to Foc-TR4 was detected in both genotypes but the response was more drastic in 'Guijiao 9' than in Williams. Specific genes involved in plant-pathogen interaction and defense signaling including MAPK, calcium, salicylic acid, jasmonic acid and ethylene pathways were analyzed and compared between 'Guijiao 9' and Williams. Genes associated with defense-related metabolites synthesis such as NB-LRR proteins, calmodulin-binding protein and phenylpropanoids biosynthesis genes were significantly up-regulated in 'Guijiao 9' resistant to Foc-TR4 infection. Taken together, this study highlights the important roles of plant hormone regulation and defense gene activation in mediating resistance in 'Guijiao 9'
Photometric calibration of the Stellar Abundance and Galactic Evolution Survey (SAGES): Nanshan One-meter Wide-field Telescope g, r, and i band imaging data
In this paper, a total of approximately 2.6 million dwarfs were constructed
as standard stars, with an accuracy of about 0.01-0.02 mag for each band, by
combining spectroscopic data from the Large Sky Area Multi-Object Fiber
Spectroscopic Telescope Data Release 7, photometric data from the corrected
Gaia Early Data Release 3, and photometric metallicities. Using the
spectroscopy based stellar color regression method (SCR method) and the
photometric-based SCR method (SCR' method), we performed the relative
calibration of the Nanshan One-meter Wide-field Telescope imaging data. Based
on the corrected Pan-STARRS DR1 photometry, the absolute calibration was also
performed. In the photometric calibration process, we analyzed the dependence
of the calibration zero points on different images (observation time),
different gates of the CCD detector, and different CCD positions. We found that
the stellar flat and the relative gain between different gates depend on time.
The amplitude of gain variation in three channels is approximately 0.5%-0.7%
relative to the other channel, with a maximum value of 4%. In addition,
significant spatial variations of the stellar flat fitting residual are found
and corrected. Using repeated sources in the adjacent images, we checked and
discovered internal consistency of about 1-2 mmag in all the filters. Using the
PS1 magnitudes synthesized by Gaia DR3 BP/RP spectra by the synthetic
photometry method, we found that the photometric calibration uniformity is
about 1-2 mmag for all the bands, at a spatial resolution of 1.3 degree. A
detailed comparison between the spectroscopy-based SCR and photometric-based
SCR method magnitude offsets was performed, and we achieved an internal
consistency precision of about 2 mmag or better with resolutions of 1.3 degree
for all the filters. Which is mainly from the position-dependent errors of the
E(B-V) used in SCR' method.Comment: 15 pages in Chinese language, 8 figures, Chinese Science Bulletin
accepted and published online
(https://www.sciengine.com/CSB/doi/10.1360/TB-2023-0052), see main results in
Figures 6, 7 and
GDI-1 preferably interacts with Rab10 in insulin-stimulated GLUT4 translocation
Insulin stimulates GLUT4 (glucose transporter 4) translocation in adipocytes and muscles. An emerging picture is that Rab10 could bridge the gap between the insulin signalling cascade and GLUT4 translocation in adipocytes. In the present study, two potential effectors of Rab10, GDI (guanine-nucleotide-dissociation inhibitor)-1 and GDI-2, are characterized in respect to their roles in insulin-stimulated GLUT4 translocation. It is shown that both GDI-1 and GDI-2 exhibit similar distribution to GLUT4 and Rab10 at the TGN (trans-Golgi network) and periphery structures. Meanwhile, GDI-1 clearly interacts with Rab10 with higher affinity, as shown by both immunoprecipitation and in vivo FRET (fluorescence resonance energy transfer). In addition, the participation of GDIs in GLUT4 translocation is illustrated when overexpression of either GDI inhibits insulin-stimulated GLUT4 translocation in 3T3-L1 adipocytes. Taken together, we propose that GDI-1 is preferentially involved in insulin-stimulated GLUT4 translocation through facilitating Rab10 recycling
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