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Hydroquinone (HQ), one of the phenolic metabolites of benzene, is widely recognized as an important participant in benzene-induced hematotoxicity. However, there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn't been fully understood yet. In this study, we treated K562 cells with 40 μmol/L HQ for 72 h, examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring (PRM), and performed bioinformatics analysis to identify interaction networks. One hundred and eighty-seven upregulated differentially expressed proteins (DEPs) and 279 downregulated DEPs were identified in HQ-exposed K562 cells, which were involved in neutrophil-mediated immunity, blood microparticle, and other GO terms, as well as the lysosome, metabolic, cell cycle, and cellular senescence-related pathways. Focusing on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways, we constructed the network of protein interactions and determined 6 DEPs (STAT1, STAT3, CASP3, KIT, STAT5B, and VEGFA) as main hub proteins with the most interactions, among which STATs made a central impact and may be potential biomarkers of HQ-induced hematotoxicity. Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification. [ABSTRACT FROM AUTHOR]

Abstract Background SnoRNAs represent an excellent model for studying the structural and functional evolution of small non-coding RNAs involved in the post-transcriptional modification machinery for rRNAs and snRNAs in eukaryotic cells. Identification of snoRNAs from Neurospora crassa, an important model organism playing key roles in the development of modern genetics, biochemistry and molecular biology will provide insights into the evolution of snoRNA genes in the fungus kingdom. Results Fifty five box C/D snoRNAs were identified and predicted to guide 71 2'-O-methylated sites including four sites on snRNAs and three sites on tRNAs. Additionally, twenty box H/ACA snoRNAs, which potentially guide 17 pseudouridylations on rRNAs, were also identified. Although not exhaustive, the study provides the first comprehensive list of two major families of snoRNAs from the filamentous fungus N. crassa. The independently transcribed strategy dominates in the expression of box H/ACA snoRNA genes, whereas most of the box C/D snoRNA genes are intron-encoded. This shows that different genomic organizations and expression modes have been adopted by the two major classes of snoRNA genes in N. crassa . Remarkably, five gene clusters represent an outstanding organization of box C/D snoRNA genes, which are well conserved among yeasts and multicellular fungi, implying their functional importance for the fungus cells. Interestingly, alternative splicing events were found in the expression of two polycistronic snoRNA gene hosts that resemble the UHG-like genes in mammals. Phylogenetic analysis further revealed that the extensive separation and recombination of two functional elements of snoRNA genes has occurred during fungus evolution. Conclusion This is the first genome-wide analysis of the filamentous fungus N. crassa snoRNAs that aids in understanding the differences between unicellular fungi and multicellular fungi. As compared with two yeasts, a more complex pattern of methylation guided by box C/D snoRNAs in multicellular fungus than in unicellular yeasts was revealed, indicating the high diversity of post-transcriptional modification guided by snoRNAs in the fungus kingdom.

ABSTRACT Benzene-induced erythropoietic depression has been proposed to be due to the production of toxic metabolites. Presently, the cytotoxicities of benzene metabolites, including phenol, catechol, hydroquinone, and 1,2,4-benzenetriol, to erythroid progenitor-like K562 cells were investigated. After exposure to these metabolites, K562 cells showed significant inhibition of viability and apoptotic characteristics. Each metabolite caused a significant increase in activities of caspase-3, -8, and -9, and pretreatment with caspase-3, -8, and -9 inhibitors significantly inhibited benzene metabolites-induced phosphatidylserine exposure. These metabolites also elevated expression of Fas and FasL on the cell surface. After exposure to benzene metabolites, K562 cells showed an increase in reactive oxygen species level, and pretreatment with N-acetyl- l-cysteine significantly protected against the cytotoxicity of each metabolite. Interestingly, the control K562 cells and the phenol-exposed cells aggregated together, but the cells exposed to other metabolites were scattered. Further analysis showed that hydroquione, catechol, and 1,2,4-benzenetriol induced a decrease in the cell surface sialic acid levels and an increase in the cell surface sialidase activity, but phenol did not cause any changes in sialic acid levels and sialidase activity. Consistently, an increase in expression level of sialidase Neu3 mRNA and a decrease in mRNA level of sialyltransferase ST3GAL3 gene were detected in hydroquione-, catechol-, or 1,2,4-benzenetriol-treated cells, but no change in mRNA levels of two genes were found in phenol-treated cells. In conclusion, these benzene metabolites could induce apoptosis of K562 cells mainly through caspase-8-dependent pathway and ROS production, and sialic acid metabolism might play a role in the apoptotic process. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1437-1451, 2014. [ABSTRACT FROM AUTHOR]

RNA interference is a gene silencing phenomenon mediated by short double-stranded RNAs, which has become a widely used research technology for reverse genetics. In order to make students understand the technology better, the students were required to select target genes, to design small interfering RNAs (siRNAs) and primers, and then to test the effect of gene silencing mediated by siRNAs. Taking the fifth group in 2018 as an example, Mus musculus acyl-CoA synthetase long-chain family member 1 (Acsl1) was selected as the target gene, two pairs of siRNAs targeting Acsl1 mRNA were designed and transfected into 3T3-L1 by electroporation, then the total RNAs were extracted and synthesized to cDNA, and the expression levels of mRNAs were finally tested by relative quantitative PCR. The results showed that both pairs of siRNAs had more than 60% silencing effects. In the past three years, about 83% of the students completed all the experiments successfully and screened out at least a pair of effective siRNA. This teaching practice for undergraduates enhances students' understanding of RNA interference principle and technology, and exercises students' lab experience and scientific research ability.

Aim: To report the visual outcomes and refractive status in premature infants with and without retinopathy of prematurity (ROP) who were or not treated., Methods: The clinical records of all premature infants with or without ROP and with or without treatment between 2007 and 2017 were retrospectively reviewed. Basic demographic data, serial changes in ROP incidence, treatment and outcomes, and the refractive states were analyzed. Correlations among myopia and astigmatism progression, birth weight, gestational age, and treatment methods were also analyzed., Results: A total of 562 screened premature infants (all Chinese, 1124 eyes), were recruited with a 378:184 male-to-female ratio. Birth weight did not directly influence ROP incidence. The overall ROP incidence was 16.55% (93/562 cases). The incidences in boys and girls were 16.14% (33/378 cases) and 17.39% (32/184 cases), respectively, and this difference was not significant. However, all infants with serious ROP (stage IV and V) were male. Myopia combined with astigmatism was common in premature infants with and without ROP (30.99%, 172/555 cases), and myopic refraction (including myopia and myopia combined with astigmatism) was more common in premature infants with ROP (48.84%, 42/86 cases). In the >8.00 diopter group, there were significantly more ROP infants than without ROP. Myopic refraction (including myopia and myopia combined with astigmatism) was most common in infants with ROP after treatment (63.63%, 7/11 cases)., Conclusion: The refractive state is different between premature infants and mature infants. Those treated for ROP had a higher chance of developing myopia, astigmatism, and higher diopter.

In this study, Embryogenic and non-embryogenic calli were separately obtained by cultivation of leaf segments on MS medium containing and not containing 2,4-D 0.2 mg/L. The calli were transferred to an 2,4-D-free MS medium containing different concentrations of (45)Ca(2+) and EGTA cultured, and microscopic examination of tissue sliced, gamma-ray energy spectrum analysis, ELISA and two-dimensional polyacrylamide-gel electrophoresis were used to study the relation between changes in Ca(2+) concentration and protein composition changes during somatic embryogenesis. The results showed that: (1) Calli of dedifferentiation were obtained by cultivating in the inductive medium (MS+2,4-D 0.2 mg/L) and then transferred to the 2,4-D-free (MS) differentiation medium. After cultivating, the large number of embryogenic cells divided and somatic embryogenic calli (EC) were formed; embryogenic cell differentiation and somatic embryo ware not formed when the dedifferentiation calli, which were cultivated in the inductive medium without 2,4-D, ware transferred to the cultivating of differentiation, so calli were called non-embryogenic calli (NEC). (2) SE frequency of EC was rised with exogenous Ca(2+) concentration was going up, and adding peak value (70.5% to 74.5%) when Ca(2+)concentration was from 0.8 to 1.6 mmol/L, then SE frequency was dropped markedly with Ca(2+) concentration was farther increasing. Formation of meristematic cell aggregates of NEC was also enhanced when exogenous Ca(2+) concentration was from 0.8 to 1.6 mmol/L. (3) After adding EGTA, which was Ca(2+) antagonist, SE frequency was dropped markedly, and SE frequency was fallen along with increased of EGTA concentration. When EGTA concentration went up to 1.2 micromol/L, SE frequency dropped to 5%, and the formation of meristematic cell aggregates on NEC was inhibited. (4) When 2 microCi (45)Ca(2+)/mL was added, the uptake of (45)Ca(2+) by EC and NEC was different, two uptake peaks of (45)Ca(2+)appeared in EC at the embryogenic cell differentiation of stage, and the uptake of (45)Ca(2+) of EC was 4-5 times higher than that of NEC, and the uptake frequency of (45)Ca(2+) improved from 54.1% to 74.5%. The uptake of (45)Ca(2+) by NEC during development not only was lower than that by EC but also there were no such marked peak as those with EC. (5) The CaM content examined by ELISA was increased markedly at multi-cellular embryo and globular embryoid stage of EC. After adding Ca(2+), the CaM content increased significantly, the CaM content of EC was 2-3 times that of NEC. (6) The IEF/SDS-PAGE results showed that the numbers and amount of protein components were widely different between the two kinds of callus with different morphogenesis patterns, the number of proteins of EC had more components than those of NEC. The largest differences protein species presented with Ca(2+) ware added, the more proteins presented on the range of molecular weight was from 43 kD to 66 kD and pI values was from 4.0 to 7.0.

In order to research the function mechanism of the 2,4-D during the development of plant somatic embryogenesis, we studied its function mechanism and relationship with the space-time distributing of Ca2+ content and ATPase activity on somatic embryogenesis of Lycium barbarum L. The possible effects on 2,4-dichlorophenoxyacetic acid (2,4-D) induced somatic embryogenesis and changes of Ca2+ and ATPase active at different development period of somatic embryogenesis. The result showed: The 2,4-D was a key hormone for induced embryonic state of Lycium barbarum L. The embryonic callus and non-embryonic callus was separately obtained in the medium that contains the auxin 2,4-D and lack 2,4-D. In the present study, we have observed the Ca2+ was more abundant in the further intercellular matrix and on the cell wall at the multi-cellular stage, and Ca2+ was concentrated in the plasma membrane and vacuoles membrane during embryonic cell differentiate and division, to the globular embryo, more Ca2+ was seen in the nucleus. Afterward, it was also observed to be distributed in the thicken cell wall and intercellular matrix. At the same process, the variations of ATPase activity and Ca2+ were highly similar, ATPase activity was mainly located on the plasma membrane in early embryogenic cells. With further development, it was also observed to be distributed in endoplasm, nucleus and vacuoles, with the thickening of embryogenic cell wall, ATPase activity was found in the thickened region and the intercellular space. However, the variations of ATPase activity and Ca2+ have not clearly observed variety dynamics at the nonembryogenic callus, and with further vacuolation of nonembryogenic cell, Ca2+ content and ATPase activity gradually drop. It was indicated there was a closely relationship between the dynamics of Ca2+ and ATPase activity in somatic embryogenesis by 2,4-D induced. And the space-time distribution of Ca2+ and ATPase activity play a key role on signal transmission and the regulation of relevant gene expression.