Study of impacts of two types of cellular aging on the yeast bud morphogenesis.

Understanding the mechanisms of the cellular aging processes is crucial for attempting to extend organismal lifespan and for studying age-related degenerative diseases. Yeast cells divide through budding, providing a classical biological model for studying cellular aging. With their powerful genetics, relatively short cell cycle, and well-established signaling pathways also found in animals, yeast cells offer valuable insights into the aging process. Recent experiments suggested the existence of two aging modes in yeast characterized by nucleolar and mitochondrial declines, respectively. By analyzing experimental data, this study shows that cells evolving into those two aging modes behave differently when they are young. While buds grow linearly in both modes, cells that consistently generate spherical buds throughout their lifespan demonstrate greater efficacy in controlling bud size and growth rate at young ages. A three-dimensional multiscale chemical-mechanical model was developed and used to suggest and test hypothesized impacts of aging on bud morphogenesis. Experimentally calibrated model simulations showed that during the early stage of budding, tubular bud shape in one aging mode could be generated by locally inserting new materials at the bud tip, a process guided by the polarized Cdc42 signal. Furthermore, the aspect ratio of the tubular bud could be stabilized during the late stage as observed in experiments in this work. The model simulation results suggest that the localization of new cell surface material insertion, regulated by chemical signal polarization, could be weakened due to cellular aging in yeast and other cell types, leading to the change and stabilization of the bud aspect ratio.

Role of 8-hydroxyguanine DNA glycosidase 1 deficiency in exacerbating diabetic cardiomyopathy through the regulation of insulin resistance.

Diabetic cardiomyopathy (DCM) is a heart failure syndrome, and is one of the major causes of morbidity and mortality in diabetes. DCM is mainly characterized by ventricular dilation, myocardial hypertrophy, myocardial fibrosis and cardiac dysfunction. Clinical studies have found that insulin resistance is an independent risk factor for DCM. However, its specific mechanism of DCM remains unclear. 8-hydroxyguanine DNA glycosylase 1(OGG1)is involved in DNA base repair and the regulation of inflammatory genes. In this study, we show that OGG1 was associated with the occurrence of DCM. for the first time. The expression of OGG1 was increased in the heart tissue of DCM mice, and OGG1 deficiency aggravated the cardiac dysfunction of DCM mice. Metabolomics show that OGG1 deficiency resulted in obstruction of glycolytic pathway. At the molecular level, OGG1 regulated glucose uptake and insulin resistance by interacting with PPAR-γ in vitro. In order to explore the protective effect of exogenous OGG1 on DCM, OGG1 adeno-associated virus was injected into DCM mice through tail vein in the middle stage of the disease. We found that the overexpression of OGG1 could improve cardiac dysfunction of DCM mice, indicating that OGG1 had a certain therapeutic effect on DCM. These results demonstrate that OGG1 is a new molecular target for the treatment of DCM and has certain clinical significance.

8-Oxoguanine DNA glycosylase protects cells from senescence via the p53-p21 pathway.

Cellular senescence is an important factor leading to pulmonary fibrosis. Deficiency of 8-oxoguanine DNA glycosylase (OGG1) in mice leads to alleviation of bleomycin (BLM)-induced mouse pulmonary fibrosis, and inhibition of the OGG1 enzyme reduces the epithelial mesenchymal transition (EMT) in lung cells. In the present study, we find decreased expression of OGG1 in aged mice and BLM-induced cell senescence. In addition, a decrease in OGG1 expression results in cell senescence, such as increases in the percentage of SA-ß-gal-positive cells, and in the p21 and p-H2AX protein levels in response to BLM in lung cells. Furthermore, OGG1 promotes cell transformation in A549 cells in the presence of BLM. We also find that OGG1 siRNA impedes cell cycle progression and inhibits the levels of telomerase reverse transcriptase (TERT) and LaminB1 in BLM-treated lung cells. The increase in OGG1 expression results in the opposite phenomenon. The mRNA levels of senescence-associated secretory phenotype (SASP) components, including IL-1α, IL-1ß, IL-6, IL-8, CXCL1/CXCL2, and MMP-3, in the absence of OGG1 are obviously increased in A549 cells treated with BLM. Interestingly, we demonstrate that OGG1 binds to p53 to inhibit the activation of p53 and that silencing of p53 reverses the inhibition of OGG1 on senescence in lung cells. Additionally, the augmented cell senescence is shown in vivo in OGG1-deficient mice. Overall, we provide direct evidence in vivo and in vitro that OGG1 plays an important role in protecting tissue cells against aging associated with the p53 pathway.

Apurinic/apyrimidinic endonuclease 1 regulates palmitic acid-mediated apoptosis in cardiomyocytes via endoplasmic reticulum stress.

Cardiomyocyte apoptosis caused by fat metabolism disorder plays an essential role in the pathogenesis of diabetic cardiomyopathy (DCM). Apurinic/apyrimidinic endonuclease 1 (APE1) has multiple functions, including regulating redox and DNA repair. However, the role of APE1 in the pathogenesis of DCM remains unclear. To investigate the mechanism of APE1 on high-fat induced apoptosis in H9C2 cells, we treated H9C2 cells with palmitic acid (PA) as an apoptosis model caused by hyperlipidemia. We found that PA reduced the viability and increased apoptosis of H9C2 cells by inducing up-regulation of APE1 protein and endoplasmic reticulum (ER) stress. APE1 knockdown enhanced PA-induced apoptosis, and ER stress and overexpression of APE1 demonstrated the opposite effect. Furthermore, APE1 regulated PA-induced apoptosis via ER stress. The APE1 mutant (C65A, lack of redox regulation) loses its protective effect against ER stress and apoptosis. These findings indicate that APE1 protects PA-induced H9C2 cardiomyocyte apoptosis through ER stress via its redox-regulated function. This study provided new insights into the therapy for DCM.

New insights into the degradation and detoxification of methylene blue using heterogeneous-Fenton catalyzed by sustainable siderite.

The huge application of synthetic dyes caused a severe impact in the environment. In the present study, a physico-chemical strategy of heterogeneous-Fenton catalyzed by the natural ferrous ore has been established for toxic chemical degradation, of which the complex and high-expense repetitive pH adjustment procedures were escaping. And this natural heterogeneous catalyst also could be recycled and sustainable for toxic substances treatment involved in synergetic adsorption and oxidation. The siderite, served as an adsorbent and catalyst for the degradation of methylene blue (MB). Siderite exhibited a better adsorption capacity with a saturated adsorption capacity of ∼11.08 mg/g. Batch adsorption experiments have verified that adsorption rate and adsorption equilibrium followed pseudo-second-order rate model and Langmuir isotherm equation, respectively. The combination with H2O2, showed significant enhancement of MB degradation without any pH adjustment. The effect of siderite dosage, H2O2 dosage, MB concentration, initial pH, and reaction temperature on MB degradation was investigated, which also has indicated the excellent catalytic performance of siderite. About 99.71% of MB was degraded in 480 min with initial pH of 7.0, reaction temperature of 25 °C, siderite, and H2O2 dosage of 2.5 g/L and 122.38 mM, respectively. It was found that siderite could be reused and remained high degradation efficiency on MB after 5 times reutilization, which also could demonstrate the sustainable and effective process to degrade organic pollution. The generation of reactive species including ·OH and O2·- have been confirmed based on scavenger test and electron spin resonance (ESR) analysis, which was dominated by heterogeneous reaction. The possible degradation mechanisms of MB have been predicted based on spectrum scanning and GC-MS analysis. Moreover, acute toxicity assessment with marine photobacterium Vibrio fisheri was conducted to investigate the toxicity change in the adsorption/oxidation coupled process. This sustainable heterogeneous-Fenton technology has been verified as a promising and applicable process for toxic organic chemicals removal due to effective mineralization and detoxification assisted with the natural ore mineral through the simple operation and mild condtions.

Knockdown of RABL3 suppresses the proliferation and invasion of oral squamous cell carcinoma through inactivating the FAK/AKT pathway.

Rab-like 3 (RABL3) is a member of Rab family that is related with several kinds of cancers. However, the functional roles of RABL3 in oral squamous cell carcinoma (OSCC) remain largely unknown. In the current study, we examined the expression levels of RABL3 in OSCC tissues and cell lines. The results showed that RABL3 expression was markedly increased in OSCC tissues and cell lines. Knockdown of RABL3 significantly suppressed the proliferation, migration and invasion of OSCC cells. Overexpression of RABL3 exhibited opposite effects with RABL3 knockdown. In vivo assay demonstrated that knockdown of RABL3 suppressed the tumorigenesis of OSCC. Moreover, RABL3 regulated the activation of focal adhesion kinase (FAK)/protein kinase B (Akt) signaling pathway in OSCC cells. Inhibition of FAK reversed the effects of RABL3 overexpression on cell proliferation, migration and invasion of OSCC cells. In conclusion, these findings demonstrated that RABL3 acted as an oncogene in OSCC, which was attributed to the regulation of FAK/Akt pathway. Thus, RABL3 may be potential therapeutic target for the treatment of OSCC.

Neuroprotective effects of Ginkgolide B in focal cerebral ischemia through selective activation of prostaglandin E2 receptor EP4 and the downstream transactivation of epidermal growth factor receptor.

The present study was undertaken to identify whether prostaglandin E2 receptor is the potential receptor/binding site for Ginkgolide A, Ginkgolide B, Ginkgolide K, and Bilobalide, the four main ingredients of the Ginkgo biloba L., leaves. Using functional assays, we identified EP4, coupled with Gs protein, as a target of Ginkgolide B. In human neuroblastoma SH-SY5Y cells suffered from oxygen-glucose deprivation/reperfusion, Ginkgolide B-activated PKA, Akt, and ERK1/2 as well as Src-mediated transactivation of epidermal growth factor receptor. These resulted in downstream signaling pathways, which enhanced cell survival and inhibited apoptosis. Knockdown of EP4 prevented Ginkgolide B-mediated Src, epidermal growth factor receptor (EGFR), Akt, and ERK1/2 phosphorylation and neuroprotective effects. Moreover, Src inhibitor prevented Ginkgolide B-mediated EGFR transactivation and the downstream Akt and ERK1/2 activation, while the phosphorylation of PKA induced by Ginkgolide B was not affected, indicating Ginkgolide B might transactivate EGFR in a ligand-independent manner. EP4 knockdown in a rat middle cerebral artery occlusion (MCAO) model prevented Ginkgolide B-mediated infarct size reduction and neurological assessment improvement. At the same time, the increased expressions of p-Akt, p-ERK1/2, p-PKA, p-Src, and p-EGFR and the deceased expression of cleaved capases-3 induced by Ginkgolide B in cerebral cortex were blocked due to EP4 knockdown. In conclusion, Ginkgolide B exerts neuroprotective effects in rat MCAO model through the activation of EP4 and the downstream transactivation of EGFR.

[Analysis of clinical features and genetic variants in a child with creatine deficiency syndrome].

OBJECTIVE: To explore the clinical features and genetic basis for a patient diagnosed with creatine deficiency syndrome (CDS). METHODS: The patient was subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing. The level of creatine was determined by using a magnetic resonance spectrum (MRS) method. RESULTS: The patient presented with development delay and poor response to stimuli. No obvious abnormality was found with his muscle tone and strength of his limbs. Borderline EEG was detected. MRI showed abnormal development of the white matter and dysplasia of corpus callosum. Urine organic acid screening has shown increased glycerin-3-phosphate. WES revealed that the patient has carried compound heterozygous variants of the GAMT gene, namely c.412C>T and IVS4-1G>A, which were respectively derived from his mother and father. MRS showed reduced creatine in bilateral basal ganglia. Functional study of the splicing site suggested that the IVS4-1G>A variant has resulted skipping of exon 5 upon splicing. CONCLUSION: The compound variants of the GAMT gene probably underlay the disease in this child. Above finding has enriched the spectrum of GAMT gene variants.

Sirt1 regulates acrosome biogenesis by modulating autophagic flux during spermiogenesis in mice.

Sirt1 is a member of the sirtuin family of proteins and has important roles in numerous biological processes. Sirt1-/- mice display an increased frequency of abnormal spermatozoa, but the mechanism of Sirt1 in spermiogenesis remains largely unknown. Here, we report that Sirt1 might be directly involved in spermiogenesis in germ cells but not in steroidogenic cells. Germ cell-specific Sirt1 knockout mice were almost completely infertile; the early mitotic and meiotic progression of germ cells in spermatogenesis were not obviously affected after Sirt1 depletion, but subsequent spermiogenesis was disrupted by a defect in acrosome biogenesis, which resulted in a phenotype similar to that observed in human globozoospermia. In addition, LC3 and Atg7 deacetylation was disrupted in spermatids after knocking out Sirt1, which affected the redistribution of LC3 from the nucleus to the cytoplasm and the activation of autophagy. Furthermore, Sirt1 depletion resulted in the failure of LC3 to be recruited to Golgi apparatus-derived vesicles and in the failure of GOPC and PICK1 to be recruited to nucleus-associated acrosomal vesicles. Taken together, these findings reveal that Sirt1 has a novel physiological function in acrosome biogenesis.

Thyroxine Affects Lipopolysaccharide-Induced Macrophage Differentiation and Myocardial Cell Apoptosis via the NF-κB p65 Pathway Both In Vitro and In Vivo.

BACKGROUND: Numerous studies have demonstrated that the inflammatory response is involved in the progression of lipopolysaccharide- (LPS-) induced myocardial cell apoptosis. Accumulating evidence has shown that thyroxine participates in diseases by downregulating the inflammatory response. This study aimed at investigating whether thyroxine alleviates LPS-induced myocardial cell apoptosis. METHODS: Bone marrow-derived macrophages (Mø) were treated with LPS and thyroxine, and Mø differentiation and Mø-related cytokine expression were measured. The effect of Mø differentiation on mouse cardiomyocyte (MCM) apoptosis was also detected in vitro. In addition, C57BL/6 mice underwent thyroidectomy and were treated with LPS 35 days later; subsequently, Mø differentiation and myocardial cell apoptosis in hearts were analyzed. To determine whether the nuclear factor-kappa B (NF-κB) p65 pathway mediates the effect of thyroxine on Mø differentiation and myocardial cell apoptosis, the specific NF-κB p65 pathway inhibitor JSH-23 was administered to mice that underwent a thyroidectomy. RESULTS: Levothyroxine treatment significantly reduced the activation of the NF-κB p65 pathway, decreased M1 macrophage (Mø1) differentiation and Mø1-related cytokine mRNA levels in LPS-treated Mø, and increased M2 macrophage (Mø2) differentiation and Mø2-related cytokine mRNA expression. The protective effects of levothyroxine on MCM apoptosis mediated by LPS-treated Mø were alleviated by JSH-23. In mice, thyroidectomy aggravated LPS-induced cardiac injury and cardiac dysfunction, further promoted NF-κB p65 activation, and increased cardiac Mø1 expression and myocardial cell apoptosis but decreased cardiac Mø2 expression. JSH-23 treatment significantly ameliorated the thyroidectomy-induced increases in myocardial cell apoptosis and Mø differentiation. CONCLUSIONS: Thyroxine alleviated the Mø1/Mø2 imbalance, reduced the inflammatory response, decreased myocardial cell apoptosis, and protected against cardiac injury and cardiac dysfunction in LPS-treated mice. Thyroxine may be a novel therapeutic strategy to prevent and treat LPS-induced cardiac injury.

[Clinical and genetic features of children with hereditary spherocytosis: an analysis of 4 cases].

Four children (two boys and two girls), aged from 3 years and 7 months to 5 years, had mild or moderate anemia, mild hepatosplenomegaly, jaundice (mainly an increase in indirect bilirubin), an increase in the percentages of reticulocytes and spherical erythrocytes in peripheral blood smear and an increase in erythrocyte osmotic brittleness. High-throughput sequencing found two novel mutations in the SLC4A1 gene, c.37G>A and c.340T>C, in case 1 and case 2 respectively, and these two mutations were predicted to be pathogenic by Mutation Taster. The Polyphen2 scores of these two mutations were 0.87 and 0.83 respectively, which suggested that these mutations were probably damaging. The SIFT scores of these two mutations were 0.008 and 0.09 respectively, suggesting that these mutations were probably damaging. No abnormality in this gene was found in their parents. Two reported heterozygous mutations in the ANK1 gene, c.830A>G and c.985G>C, were found in case 3 and case 4 respectively. Gene detection was not performed for the parents of case 3. The mother of case 4 was diagnosed with hereditary spherocytosis and had a heterozygous mutation of c.985G>C in the ANK1 gene. All four children were diagnosed with hereditary spherocytosis. Case 3 had a hemoglobin level of <80 g/L and underwent splenectomy at the age of 5 years and 6 months, and regular postoperative reexamination showed a hemoglobin level of >105 g/L. Hereditary spherocytosis is a hereditary hemolytic disease caused by abnormality in erythrocyte membrane protein, and gene detection helps to make a confirmed diagnosis.

Multi-scale computational study of the mechanical regulation of cell mitotic rounding in epithelia.

Mitotic rounding during cell division is critical for preventing daughter cells from inheriting an abnormal number of chromosomes, a condition that occurs frequently in cancer cells. Cells must significantly expand their apical area and transition from a polygonal to circular apical shape to achieve robust mitotic rounding in epithelial tissues, which is where most cancers initiate. However, how cells mechanically regulate robust mitotic rounding within packed tissues is unknown. Here, we analyze mitotic rounding using a newly developed multi-scale subcellular element computational model that is calibrated using experimental data. Novel biologically relevant features of the model include separate representations of the sub-cellular components including the apical membrane and cytoplasm of the cell at the tissue scale level as well as detailed description of cell properties during mitotic rounding. Regression analysis of predictive model simulation results reveals the relative contributions of osmotic pressure, cell-cell adhesion and cortical stiffness to mitotic rounding. Mitotic area expansion is largely driven by regulation of cytoplasmic pressure. Surprisingly, mitotic shape roundness within physiological ranges is most sensitive to variation in cell-cell adhesivity and stiffness. An understanding of how perturbed mechanical properties impact mitotic rounding has important potential implications on, amongst others, how tumors progressively become more genetically unstable due to increased chromosomal aneuploidy and more aggressive.

H2B ubiquitination regulates meiotic recombination by promoting chromatin relaxation.

Meiotic recombination is essential for fertility in most sexually reproducing species, but the molecular mechanisms underlying this process remain poorly understood in mammals. Here, we show that RNF20-mediated H2B ubiquitination is required for meiotic recombination. A germ cell-specific knockout of the H2B ubiquitination E3 ligase RNF20 results in complete male infertility. The Stra8-Rnf20-/- spermatocytes arrest at the pachytene stage because of impaired programmed double-strand break (DSB) repair. Further investigations reveal that the depletion of RNF20 in the germ cells affects chromatin relaxation, thus preventing programmed DSB repair factors from being recruited to proper positions on the chromatin. The gametogenetic defects of the H2B ubiquitination deficient cells could be partially rescued by forced chromatin relaxation. Taken together, our results demonstrate that RNF20/Bre1p-mediated H2B ubiquitination regulates meiotic recombination by promoting chromatin relaxation, and suggest an old drug may provide a new way to treat some oligo- or azoospermia patients with chromatin relaxation disorders.

HIV prevalence among female sex workers in Guigang City, Guangxi, China: an 8-year consecutive cross-sectional study.

BACKGROUND: Female sex workers (FSW) are a population that are at high risk for HIV infection, and their HIV/AIDS knowledge levels and sexual behaviors are of concern. This study describes changes in HIV prevalence and factors associated among female sex workers in Guigang City, Guangxi, one of the highest HIV prevalence areas in China. METHODS: Data were derived from an annual cross-sectional venue-based survey, 2008 to 2015, in the form of sentinel surveillance. The participants were recruited using cluster sampling. FSW aged 16 years and above who completed a questionnaire and HIV testing. Both descriptive and multi-level analyses were used to explore factors associated with changes in HIV prevalence. RESULTS: Seven thousand four hundred ninety-six FSW were recruited in this study. HIV prevalence among FSW in Guigang City fell into two periods, one with an increasing trend (2008-2011) and one with a decline (2012-2015). Differences between these time periods included age, relationship status, HIV knowledge, consistent condom use, lifetime illicit drug use, history of sexually transmitted infection in the past year, HIV testing, receipt of a condom distribution and education program or HIV counseling and testing, and peer education services. CONCLUSIONS: Since 2012, a reduction in HIV prevalence among FSW in Guigang City has been observed. The decline of HIV prevalence was associated with coinciding changes in demographic characteristics of FSW, improvement of HIV knowledge and safer sexual behaviors, and a program that promotes condom use, HIV counseling & testing, and peer education.

Degradation of the Separase-cleaved Rec8, a Meiotic Cohesin Subunit, by the N-end Rule Pathway.

The Ate1 arginyltransferase (R-transferase) is a component of the N-end rule pathway, which recognizes proteins containing N-terminal degradation signals called N-degrons, polyubiquitylates these proteins, and thereby causes their degradation by the proteasome. Ate1 arginylates N-terminal Asp, Glu, or (oxidized) Cys. The resulting N-terminal Arg is recognized by ubiquitin ligases of the N-end rule pathway. In the yeastSaccharomyces cerevisiae, the separase-mediated cleavage of the Scc1/Rad21/Mcd1 cohesin subunit generates a C-terminal fragment that bears N-terminal Arg and is destroyed by the N-end rule pathway without a requirement for arginylation. In contrast, the separase-mediated cleavage of Rec8, the mammalian meiotic cohesin subunit, yields a fragment bearing N-terminal Glu, a substrate of the Ate1 R-transferase. Here we constructed and used a germ cell-confinedAte1(-/-)mouse strain to analyze the separase-generated C-terminal fragment of Rec8. We show that this fragment is a short-lived N-end rule substrate, that its degradation requires N-terminal arginylation, and that maleAte1(-/-)mice are nearly infertile, due to massive apoptotic death ofAte1(-/-)spermatocytes during the metaphase of meiosis I. These effects ofAte1ablation are inferred to be caused, at least in part, by the failure to destroy the C-terminal fragment of Rec8 in the absence of N-terminal arginylation.

The histone codes for meiosis.

Meiosis is a specialized process that produces haploid gametes from diploid cells by a single round of DNA replication followed by two successive cell divisions. It contains many special events, such as programmed DNA double-strand break (DSB) formation, homologous recombination, crossover formation and resolution. These events are associated with dynamically regulated chromosomal structures, the dynamic transcriptional regulation and chromatin remodeling are mainly modulated by histone modifications, termed 'histone codes'. The purpose of this review is to summarize the histone codes that are required for meiosis during spermatogenesis and oogenesis, involving meiosis resumption, meiotic asymmetric division and other cellular processes. We not only systematically review the functional roles of histone codes in meiosis but also discuss future trends and perspectives in this field.

[Effect of high-fat diet on expression of transient receptor potential vanilloid 1 in respiratory tract and dorsal root ganglion of mice].

OBJECTIVE: To investigate the effect of high-fat diet on the expression of transient receptor potential vanilloid 1 (TRPV1) in the respiratory system and the dorsal root ganglion (DRG) of mice, as well as its effect on the excitability of sensory neurons. METHODS: A total of 20 C57BL/6 mice were randomly divided into normal-diet (ND) group and high-fat diet (HFD) group, with 10 mice in each group. The mice were given corresponding diets and body weights were monitored. After 7 weeks of feeding, lung tissue, bronchial tissue, and DRG at thoracic segments 3-4 were collected and immunohistochemical staining was performed. A patch clamp was used to measure the number of action potentials and TRPV1 current intensity in the DRG. RESULTS: After 7 weeks of feeding, the HFD group had significantly greater mean weight gain than the ND group (6.4±2.6 g vs 2.3±0.5 g; P<0.001). The HFD group had significantly higher expression of TRPV1 in the bronchus, pulmonary alveoli, and DRG than the ND group (P<0.05). Compared with the ND group, the HFD group had significant increases in the TRPV1 current intensity and number of action potentials in the DRG (P<0.05). CONCLUSIONS: High-fat diet induces a significant increase in body weight and leads to high expression of TRPV1 and high excitability in the respiratory system and the peripheral sensory neurons. This suggests that TRPV1 may be an important factor in the physiopathological mechanisms of bronchial hyperresponsiveness.

[Clinical features and pathogenic gene detection of Diamond-Blackfan anemia].

OBJECTIVE: To investigate the clinical features of Diamond-Blackfan anemia (DBA) and related pathogenic genes. METHODS: A retrospective analysis was performed for the clinical data of two children with DBA, and related literature was reviewed. RESULTS: The two children with DBA (2-3 months old) manifested with severe normochromic normocytic anemia, decreased reticulocyte count, and increased serum iron and serum ferritin. Normal white blood cell and platelet counts were noted in the two patients. Bone marrow examination showed a decreased percentage of erythrocytes and rare normoblasts in the two patients. Gene screening showed a reported pathogenic heterozygous mutation in RPS19 gene, c.212G>A (p. Gly71Glu), in one patient, and there were no mutations in his parents. In the other patient, gene screening showed a heterozygous mutation in RPL5 gene, c.740T>C (p. I247L), which had not been reported in literature, and there were no mutations in her parents. A bioinformatic analysis showed that this might be a pathogenic mutation. CONCLUSIONS: The onset age of DBA is early infancy in most children, with a manifestation of erythroid deficiency. RPS19 and RPL5 gene mutations are common causes of this disease. Molecular detection helps with the early diagnosis of DBA.

Heixuedian (heix), a potential melanotic tumor suppressor gene, exhibits specific spatial and temporal expression pattern during Drosophila hematopoiesis.

The Drosophila heixuedian (heix) is the ortholog of human UBIAD1 gene (a.k.a TERE1). The protein product of UBIAD1/heix has multiple enzymatic activities, including the vitamin K2 and the non-mitochondrial CoQ10 biosynthesis. However, the expression pattern of UBIAD1/Heix during metazoan development has not been systematically studied. In this paper, we found that loss of function of heix resulted in pathological changes of larval hematopoietic system, including lymph gland hypertrophy, hemocyte overproliferation and aberrant differentiation, and melanin mass formation. Overexpression of heix cDNA under the tubulin Gal4 driver rescued the above hematopoietic defects. Interestingly, Heix was specifically expressed in plasmatocyte/macrophage lineage in srp driven EGFP positive cells on the head mesoderm during embryogenesis, while it was highly expressed in crystal cells in the primary lobes of the third instar larval lymph gland. Using qRT-PCR analysis, loss of function of heix caused aberrant activation of multiple hemocyte proliferation-related as well as immune-related pathways, including JAK/STAT pathway, Ras/MAPK pathway, IMD pathway and Toll pathway. These data suggested that heix is a potential melanotic tumor suppressor gene and plays a pivotal role in both hemocytes proliferation and differentiation in Drosophila.

Nontargeted Screening Method for Illegal Additives Based on Ultrahigh-Performance Liquid Chromatography-High-Resolution Mass Spectrometry.

Identification of illegal additives in complex matrixes is important in the food safety field. In this study a nontargeted screening strategy was developed to find illegal additives based on ultrahigh-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS). First, an analytical method for possible illegal additives in complex matrixes was established including fast sample pretreatment, accurate UHPLC separation, and HRMS detection. Second, efficient data processing and differential analysis workflow were suggested and applied to find potential risk compounds. Third, structure elucidation of risk compounds was performed by (1) searching online databases [Metlin and the Human Metabolome Database (HMDB)] and an in-house database which was established at the above-defined conditions of UHPLC-HRMS analysis and contains information on retention time, mass spectra (MS), and tandem mass spectra (MS/MS) of 475 illegal additives, (2) analyzing fragment ions, and (3) referring to fragmentation rules. Fish was taken as an example to show the usefulness of the nontargeted screening strategy, and six additives were found in suspected fish samples. Quantitative analysis was further carried out to determine the contents of these compounds. The satisfactory application of this strategy in fish samples means that it can also be used in the screening of illegal additives in other kinds of food samples.