ALBERT

Description: Background: Stored, soluble histones in eggs are essential for early development, in particular during the maternally controlled early cell cycles in the absence of transcription. Histone post-translational modifications (PTMs) direct and regulate chromatin-templated transactions, so understanding the nature and function of pre-deposition maternal histones is essential to deciphering mechanisms of regulation of development, chromatin assembly, and transcription. Little is known about histone H2A pre-deposition modifications nor known about the transitions that occur upon the onset of zygotic control of the cell cycle and transcription at the mid-blastula transition (MBT). Results: We isolated histones from staged Xenopus laevis oocytes, eggs, embryos, and assembled pronuclei to identify changes in histone H2A modifications prior to deposition and in chromatin. Soluble and chromatin-bound histones from eggs and embryos demonstrated distinct patterns of maternal and zygotic H2A PTMs, with significant pre-deposition quantities of S1ph and R3me1, and R3me2s. We observed the first functional distinction between H2A and H4 S1 phosphorylation, as we showed that H2A and H2A.X-F (also known as H2A.X.3) serine 1 (S1) is phosphorylated concomitant with germinal vesicle breakdown (GVBD) while H4 serine 1 phosphorylation occurs post-MBT. In egg extract H2A/H4 S1 phosphorylation is independent of the cell cycle, chromatin assembly, and DNA replication. H2AS1ph is highly enriched on blastula chromatin during repression of zygotic gene expression while H4S1ph is correlated with the beginning of maternal gene expression and the lengthening of the cell cycle, consistent with distinct biological roles for H2A and H4 S1 phosphorylation. We isolated soluble H2A and H2A.X-F from the egg and chromatin-bound in pronuclei and analyzed them by mass spectrometry analysis to quantitatively determine abundances of S1ph and R3 methylation. We show that H2A and H4 S1ph, R3me1 and R3me2s are enriched on nucleosomes containing both active and repressive histone PTMs in human A549 cells and Xenopus embryos. Conclusions: Significantly, we demonstrated that H2A phosphorylation and H4 arginine methylation form a new class of bona fide pre-deposition modifications in the vertebrate embryo. We show that S1ph and R3me containing chromatin domains are not correlated with H3 regulatory PTMs, suggesting a unique role for phosphorylation and arginine methylation.

Description: Background: Reduced beta2-glycoprotein I (beta2-GPI) is a free thiol-containing form of beta2-GPI that displays a powerful effect in protecting endothelial cells from oxidative stress-induced cell death. The present study aims to investigate the effect of beta2-GPI or reduced beta2-GPI on ox-LDL-induced foam cell formation and on cell apoptosis and to determine the possible mechanisms. Methods: The RAW264.7 macrophage cell line was selected as the experimental material. Oil red O staining and cholesterol measurement were used to detect cholesterol accumulation qualitatively and quantitatively, respectively. Flow cytometry was used to detect cell apoptosis. Real-time quantitative PCR was used to detect the mRNA expression of the main proteins that are associated with the transport of cholesterol, such as CD36, SRB1, ABCA1 and ABCG1. Western blot analysis was used to detect the protein expression of certain apoptosis-related proteins, such as caspase-9, caspase-3, p38 MAPK/p-p38 MAPK and JNK/p-JNK. Results: Beta2-GPI or reduced beta2-GPI decreased ox-LDL-induced cholesterol accumulation (96.45 +/- 8.51 mug/mg protein vs. 114.35 +/- 10.38 mug/mg protein, p 〈 0.05;74.44 +/- 5.27 mug/mg protein vs. 114.35 +/- 10.38 mug/mg protein, p 〈 0.01) and cell apoptosis (30.00 +/- 5.10% vs. 38.70 +/- 7.76%, p 〈 0.05; 20.66 +/- 2.50% vs. 38.70 +/- 7.76%, p 〈 0.01), and there are significant differences between beta2-GPI and reduced beta2-GPI (p 〈 0.05). Reduced beta2-GPI decreased the ox-LDL-induced expression of CD36 mRNA and ABCA1 mRNA (p 〈 0.05), as well as CD36, cleaved caspase-9, cleaved caspase-3, p-p38 MAPK and p-JNK proteins (p 〈 0.05 or p 〈 0.01). Beta2-GPI did not significantly decrease the expression of ABCA1 mRNA and the p-p38 MAPK protein. Conclusions: Both beta2-GPI and reduced beta2-GPI inhibit ox-LDL-induced foam cell formation and cell apoptosis, and the latter exhibits a stronger inhibition effect. Both of these glycoproteins reduce the lipid intake of macrophages by downregulating CD36 as well as protein expression. Reduced beta2-GPI inhibits cell apoptosis by reducing the ox-LDL-induced phosphorylation of p38 MAPK and JNK, and the amount of cleaved caspase-3 and caspase-9. Beta2-GPI does not inhibit the ox-LDL-induced phosphorylation of p38 MAPK.

Description: Author Correction: Pressure-Induced Crystallization and Phase Transformation of Para -xylene Author Correction: Pressure-Induced Crystallization and Phase Transformation of 〈i〉Para〈/i〉-xylene, Published online: 14 June 2018; doi:10.1038/s41598-018-26714-9 Author Correction: Pressure-Induced Crystallization and Phase Transformation of Para -xylene

Description: Investigation of mortuary ritual is an important method to reconstruct many aspects of past societies. Due to the lack of relevant analytical work, little evidence related to organic materials in a burial can be found in China. Here we report materials collected from a burial during the excavation of the Shengedaliang site. The recovered materials were analyzed using Raman spectroscopy and plant analysis: flotation, pollen and phytolith analysis. The red pigments found scattered over the human remains were identified as cinnabar. Extracted phytoliths associated with the burial are mainly leaves from the Boraginaceae family. This is the first time that a covering of leaves have been identified with a burial in Neolithic China. The presence of “special” leaves fossil may indicate a type of “plant worship” and the identification of an important plant used in traditional Chinese medicine. The finding of the two materials allows us to better identify indicators of funerary ritual and its relationship to social inequality.