43 research outputs found

    Bovine Lhx8, a Germ Cell-SpecificNuclear Factor, Interacts with Figla

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    LIM homeobox 8 (Lhx8) is a germ cell-specific transcription factor essential for the development of oocytes during early oogenesis. In mice, Lhx8 deficiency causes postnatal oocyte loss and affects the expression of many oocyte-specific genes. The aims of this study were to characterize the bovine Lhx8 gene, determine its mRNA expression during oocyte development and early embryogenesis, and evaluate its interactions with other oocyte-specific transcription factors. The bovine Lhx8 gene encodes a protein of 377 amino acids. A splice variant of Lhx8 (Lhx8_v1) was also identified. The predicted bovine Lhx8 protein contains two LIM domains and one homeobox domain. However, one of the LIM domains in Lhx8_v1 is incomplete due to deletion of 83 amino acids near the N terminus. Both Lhx8 and Lhx8_v1 transcripts were only detected in the gonads but none of the somatic tissues examined. The expression of Lhx8 and Lhx8_v1 appears to be restricted to oocytes as none of the transcripts was detectable in granulosa or theca cells. The maternal Lhx8 transcript is abundant in GV and MII stage oocytes as well as in early embryos but disappear by morula stage. A nuclear localization signal that is required for the import of Lhx8 into nucleus was identified, and Lhx8 is predominantly localized in the nucleus when ectopically expressed in mammalian cells. Finally, a novel interaction between Lhx8 and Figla, another transcription factor essential for oogenesis, was detected. The results provide new information for studying the mechanisms of action for Lhx8 in oocyte development and early embryogenesis

    Revisiting Galaxy Evolution in Morphology in the COSMOS field (COSMOS-ReGEM):I. Merging Galaxies

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    We revisit the evolution of galaxy morphology in the COSMOS field over the redshift range 0.2≤z≤10.2\leq z \leq 1, using a large and complete sample of 33,605 galaxies with a stellar mass of log(M∗M_{\ast}/M⊙)>9.5_{\odot} )>9.5 with significantly improved redshifts and comprehensive non-parametric morphological parameters. Our sample has 13,881 (∼41.3%\sim41.3\%) galaxies with reliable spectroscopic redshifts and has more accurate photometric redshifts with a σNMAD∼0.005\sigma_{\rm NMAD} \sim 0.005. This paper is the first in a series that investigates merging galaxies and their properties. We identify 3,594 major merging galaxies through visual inspection and find 1,737 massive galaxy pairs with log(M∗M_\ast/M⊙_\odot)>10.1>10.1. Among the family of non-parametric morphological parameters including CC, AA, SS, GiniGini, M20M_{\rm 20}, AOA_{\rm O}, and DOD_{\rm O}, we find that the outer asymmetry parameter AOA_{\rm O} and the second-order momentum parameter M20M_{\rm 20} are the best tracers of merging features than other combinations. Hence, we propose a criterion for selecting candidates of violently star-forming mergers: M20>−3AO+3M_{\rm 20}> -3A_{\rm O}+3 at 0.2−6AO+3.70.2 -6A_{\rm O}+3.7 at 0.6<z<1.00.6<z<1.0. Furthermore, we show that both the visual merger sample and the pair sample exhibit a similar evolution in the merger rate at z<1z<1, with ℜ∼(1+z)1.79±0.13\Re \sim(1+z)^{1.79 \pm 0.13} for the visual merger sample and ℜ∼(1+z)2.02±0.42\Re \sim(1+z)^{2.02\pm 0.42} for the pair sample. The visual merger sample has a specific star formation rate that is about 0.16\,dex higher than that of non-merger galaxies, whereas no significant star formation excess is observed in the pair sample. This suggests that the effects of mergers on star formation differ at different merger stages.Comment: 21 pages, 12 figures; accepted for publication in Ap

    Parameter design of coal pillar in highwall mining under action of dynamic-static load

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    In view of the application of end slope shearer mining technology to recover a large amount of residual coal, the determination of reasonable width of supporting coal pillar is a key factor whether it can be safely and efficiently popularization and application, especially considering the influence of blasting vibration on the stability of supporting coal pillar. Based on the southern end slope at the open-pit coal mine of Pingshuo, field vibration test, theoretical analysis and numerical calculation were used to study the web pillar stability in open-pit highwall mining and its parameter design under the action of triangular load and blasting vibration on the side slope. Based on the theory of limit balance and the mutation theory, the stress distribution at the coal pillar was analyzed, combined with Mohr-Coulomb failure criterion. Besides, the ultimate strength function expression of coal pillar under the influence of mining height, mining width, load stress of overlying strata, cohesion and internal friction angle of coal pillar is established. The calculation formula of the maximum allowable plastic zone width and rational width of web pillar under different safety reserve factor conditions are established. The three-dimensional simple harmonic vibration response model of the supported coal pillar was established, and the blasting parameters such as the amount of single shot, elevation difference and horizontal distance of the blast center were studied on the response of the maximum instantaneous dynamic stress of the coal pillar, which revealed the influence mechanism of the blasting dynamic load effect on the width and stability of the plastic zone of the supported coal pillar and proposed the design method of the parameters of the supported coal pillar under the blasting dynamic load. The results show that the blasting vibration has a greater influence on the stability of coal pillar, and the instantaneous maximum dynamic stress response of coal pillar under the blasting dynamic load is positively correlated with the amount of single shot, and negatively correlated with the elevation difference and horizontal distance. With the increase of the maximum instantaneous dynamic stress response of coal pillar, the width of plastic zone of coal pillar increases proportionally, and the safety factor of coal pillar decays in an approximately linear pattern. The width of coal pillar under dynamic-static load is determined to be 5 m, and its reasonableness is verified by engineering practice

    Dexamethasone inhibits repair of human airway epithelial cells mediated by glucocorticoid-induced leucine zipper (GILZ).

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    BACKGROUND: Glucocorticoids (GCs) are a first-line treatment for asthma for their anti-inflammatory effects, but they also hinder the repair of airway epithelial injury. The anti-inflammatory protein GC-induced leucine zipper (GILZ) is reported to inhibit the activation of the mitogen-activated protein kinase (MAPK)-extracellular-signal-regulated kinase (ERK) signaling pathway, which promotes the repair of airway epithelial cells around the damaged areas. We investigated whether the inhibition of airway epithelial repair imposed by the GC dexamethasone (DEX) is mediated by GILZ. METHODS: We tested the effect of DEX on the expressions of GILZ mRNA and GILZ protein and the MAPK-ERK signaling pathway in human airway epithelial cells, via RT-PCR and Western blot. We further evaluated the role of GILZ in mediating the effect of DEX on the MAPK-ERK signaling pathway and in airway epithelium repair by utilizing small-interfering RNAs, MTT, CFSE labeling, wound-healing and cell migration assays. RESULTS: DEX increased GILZ mRNA and GILZ protein levels in a human airway epithelial cell line. Furthermore, DEX inhibited the phosphorylation of Raf-1, Mek1/2, Erk1/2 (components of the MAPK-ERK signaling pathway), proliferation and migration. However, the inhibitory effect of DEX was mitigated in cells when the GILZ gene was silenced. CONCLUSIONS: The inhibition of epithelial injury repair by DEX is mediated in part by activation of GILZ, which suppressed activation of the MAPK-ERK signaling pathway, proliferation and migration. Our study implicates the involvement of DEX in this process, and furthers our understanding of the dual role of GCs

    Exploring the Drivers for Changes in Lake Area in a Typical Arid Region during Past Decades

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    Lakes are important surface water bodies, and ongoing climate change is a growing threat to the hydrological cycle and water resource availability of lakes in arid regions. Accurately estimating different drivers’ contributions to lake water volume can enhance our understanding of lake variations in arid regions. In this study, we combined the land surface model and hydrological model, as well as statistical methods, to analyze the spatiotemporal heterogeneity of lake area changes and the factors affecting these changes during the past decades in Bosten Lake, Ulungur Lake, Ebinur Lake, and Sayram Lake, which are located in a typical dry region in China. The study revealed that the average amounts of river inflow, TWVF, lake ice sublimation, lake surface precipitation, and river outflow in the four lakes were 17.41 × 108 m3 yr−1, 6.60 × 108 m3 yr−1, 0.41 × 108 m3 yr−1, 0.98 × 108 m3 yr−1, and 9.12 × 108 m3 yr−1, respectively. We found that river inflow is the dominant factor affecting changes in open lake areas, while lake surface precipitation is the main factor affecting changes in closed lake areas. Our findings suggest that the main factors dominating the variability of lake water volume differ in different phases and lake types

    Bioinformatic identification of candidate biomarkers and related transcription factors in nasopharyngeal carcinoma

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    Abstract Background The incidence of nasopharyngeal carcinoma (NPC) is rare, but a certain amount of mortality remains in NPC patients. Our study aimed to identify candidate genes as biomarkers for NPC screening, diagnosis, and therapy. Methods We investigated two microarray profile datasets GSE64634 and GSE12452 to screen the potential differentially expressed genes (DEGs) in NPC. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of the DEGs were also performed. A protein-protein interaction (PPI) network of DEGs was constructed by STRING and visualized by Cytoscape software. The associated transcriptional factor regulatory network of the DEGs was also constructed. Results A total of 152 DEGs were identified from the GSE64634 and GSE12452 datasets, including 10 upregulated and 142 downregulated genes. Gene functional enrichment analysis indicated that these DEGs were enriched in the cilium movement, antimicrobial humoral response, O-glycan processing, mucosal immune response, carbohydrate transmembrane transporter activity, hormone biosynthetic process, neurotransmitter biosynthetic process, and drug metabolism-cytochrome P450 pathway. Five hub genes (DNALI1, RSPH4A, RSPH9, DNAI2, and ALDH3A1) and one significant module (score = 5.6) were obtained from the PPI network. Key transcriptional factors, such as SPI1, SIN3B, and GATA2, were identified with close interactions with these five hub DEGs from the gene-transcriptional factor network. Conclusions With the integrated bioinformatic analysis, numerous DEGs related to NPC were screened, and the hub DEGs we identified may be potential biomarkers for NPC

    RT-PCR analysis of bovine <i>Lhx8</i> and <i>Lhx8-v1</i> mRNA expression.

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    <p><b>A</b>: Expression of <i>Lhx8</i> and <i>Lhx8-v1</i> mRNA in bovine tissues. Tissues tested include spleen, stomach, brain, muscle, kidney, liver, heart, intestine, adult ovary, adult testis, fetal testis and fetal ovary. <b>B</b>: Expression of <i>Lhx8</i> and <i>Lhx8-v1</i> mRNA in bovine fetal ovaries from different gestation stages. Fetal ovaries from 90, 95, 100, 150, 160, 200, 210, 230 and 250 day fetuses were analyzed. The ages of fetuses were estimated based on crown-rump length. <b>C</b>: Expression of <i>Lhx8</i> and <i>Lhx8-v1</i> mRNA in oocytes and early embryos. Oocytes and embryos samples used in the analysis include GV- and MII-stage oocytes and 2-cell, 4-cell, 8-cell, 16-cell, and morula- and blastocyst-stage embryos. Bovine <i>RPL19</i> gene was used as a control for RNA quality.</p

    Cellular localization of bovine Lhx8 protein analyzed by a GFP reporter assay.

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    <p>HEK293 cells were transfected with GFP reporter constructs expressing either an EGFP-tagged wild type Lhx8 (Lhx8-wt) or Lhx8 mutants with either the monopartite NLS (Lhx8-ΔM-NLS) or the bipartite NLS deleted (Lhx8-ΔB-NLS). Empty pcDNA3-EGFP vector was used as a control. Nuclear DNA was stained with DAPI and cells were analyzed with a fluorescence microscope.</p

    Interaction of Lhx8 with Figla.

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    <p><b>A</b>: Yeast two-hybrid analysis of protein interactions between Lhx8 and Figla or Sohlh1. Right plate: Growth of yeast cells on DDO plate (medium lacking Leucine and tryptophan) showing successful co-transformations. Left plate: growth of yeast cells on selective QDO/X/A plate (Quadruple drop-out medium lacking leucine, tryptophan, adenine and histidine and containing X-gal) indicating protein-protein interactions. <b>B</b>: Co-IP analysis of interaction between Lhx8 and Figla. HEK293 cells were co-transfected with the expression constructs, pcDNA3.1-Lhx8-FLAG and pcDNA3.1-Figla-HA. Cell lysates were immunoprecipitated with anti-Flag antibody followed by Western blot analysis with anti-HA antibody. <b>C</b>: Direct yeast two-hybrid analysis showing LIM domains of Lhx8 are required for interaction with Figla. Right plate: Growth of yeast cells on DDO plate showing successful co-transformations. Left plate: growth of yeast cells on selective QDO/X/A plate indicating protein-protein interactions.</p
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