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1.
Cell ; 165(1): 35-44, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26997480

RESUMO

PD-1 immune checkpoint blockade provides significant clinical benefits for melanoma patients. We analyzed the somatic mutanomes and transcriptomes of pretreatment melanoma biopsies to identify factors that may influence innate sensitivity or resistance to anti-PD-1 therapy. We find that overall high mutational loads associate with improved survival, and tumors from responding patients are enriched for mutations in the DNA repair gene BRCA2. Innately resistant tumors display a transcriptional signature (referred to as the IPRES, or innate anti-PD-1 resistance), indicating concurrent up-expression of genes involved in the regulation of mesenchymal transition, cell adhesion, extracellular matrix remodeling, angiogenesis, and wound healing. Notably, mitogen-activated protein kinase (MAPK)-targeted therapy (MAPK inhibitor) induces similar signatures in melanoma, suggesting that a non-genomic form of MAPK inhibitor resistance mediates cross-resistance to anti-PD-1 therapy. Validation of the IPRES in other independent tumor cohorts defines a transcriptomic subset across distinct types of advanced cancer. These findings suggest that attenuating the biological processes that underlie IPRES may improve anti-PD-1 response in melanoma and other cancer types.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Metástase Neoplásica/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos/efeitos adversos , Proteína BRCA2/genética , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/genética , Metástase Neoplásica/genética , Nivolumabe , Transcriptoma
2.
Cell ; 162(6): 1271-85, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26359985

RESUMO

Clinically acquired resistance to MAPK inhibitor (MAPKi) therapies for melanoma cannot be fully explained by genomic mechanisms and may be accompanied by co-evolution of intra-tumoral immunity. We sought to discover non-genomic mechanisms of acquired resistance and dynamic immune compositions by a comparative, transcriptomic-methylomic analysis of patient-matched melanoma tumors biopsied before therapy and during disease progression. Transcriptomic alterations across resistant tumors were highly recurrent, in contrast to mutations, and were frequently correlated with differential methylation of tumor cell-intrinsic CpG sites. We identified in the tumor cell compartment supra-physiologic c-MET up-expression, infra-physiologic LEF1 down-expression and YAP1 signature enrichment as drivers of acquired resistance. Importantly, high intra-tumoral cytolytic T cell inflammation prior to MAPKi therapy preceded CD8 T cell deficiency/exhaustion and loss of antigen presentation in half of disease-progressive melanomas, suggesting cross-resistance to salvage anti-PD-1/PD-L1 immunotherapy. Thus, melanoma acquires MAPKi resistance with highly dynamic and recurrent non-genomic alterations and co-evolving intra-tumoral immunity.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Linfócitos T CD8-Positivos/imunologia , Metilação de DNA , Perfilação da Expressão Gênica , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Melanoma/imunologia , Fosfoproteínas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Fatores de Transcrição , Proteínas de Sinalização YAP , beta Catenina/metabolismo
4.
Pharmacol Res ; 205: 107232, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38825157

RESUMO

Type 3 resistant starch from Canna edulis (Ce-RS3) is an insoluble dietary fiber which could improve blood lipids in animals, but clinically robust evidence is still lacking. We performed a double-blind randomized controlled trial to assess the effects of Ce-RS3 on lipids in mild hyperlipidemia. One hundred and fifteen patients were included followed the recruitment criteria, and were randomly allocated to receive Ce-RS3 or placebo (native starch from Canna edulis) for 12 weeks (20 g/day). In addition to serum lipids, complete blood counts, serum inflammatory factors, antioxidant indexes, and dietary survey, 16 S rRNA sequencing technique was utilized to analyze the gut microbiota alterations. Targeted quantitative metabolomics (TQM) was used to detect metabolite changes. Compared with the placebo, Ce- RS3 significantly decreased levels of total cholesterol, lowdensity lipoprotein cholesterol, and non-high-density lipoprotein cholesterol, and increased the glutathione peroxidase. Based on the 16 S rRNA sequencing, TQM, the correlation analysis, as well as the Kyoto Encyclopedia of Genes (KEGG) and Genomes and Human Metabolome Database (HMDB) analysis, we found that Ce-RS3 could increase the abundances of genera Faecalibacterium and Agathobacter, while reduce the abundances of genera norank_f_Ruminococcaceae and Christensenellaceae_R-7_ group to regulate phenylalanine metabolism, which could reduce the fatty acid biosynthesis and fatty acid elongation in the mitochondria to lower blood lipids. Conclusively, we firstly confirmed the feasibility of Ce-RS3 for clinical application, which presents a novel, effective therapy for the mild hyperlipidemia. (Chictr. org. cn. Clinical study on anti-mild hyperlipidemia of Canna edulis RS3 resistant starch, ID Number: ChiCTR2200062871).


Assuntos
Microbioma Gastrointestinal , Hiperlipidemias , Humanos , Microbioma Gastrointestinal/efeitos dos fármacos , Método Duplo-Cego , Masculino , Pessoa de Meia-Idade , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/sangue , Hiperlipidemias/microbiologia , Feminino , Adulto , Lipídeos/sangue , Amido Resistente , Amido , Hipolipemiantes/uso terapêutico , Hipolipemiantes/farmacologia , Idoso
5.
J Assist Reprod Genet ; 41(7): 1893-1906, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38676843

RESUMO

PURPOSE: Male cancer survivors experience confusion about fertility following cancer treatment. The aims of this study were to evaluate survivors' semen quality in different tumor type groups in China and to analyze the current situation and challenges of male cancer patients with sperm cryopreservation. METHODS: This was a multicenter retrospective study of male patients with cancer who underwent sperm cryopreservation in 16 regions of the national sperm banks over an 11-year period from 2010 to 2020. RESULTS: The number of male cancer patients with sperm cryopreservation showed an overall upward trend. The development of male cancer fertility preservation (FP) in the eastern, central, and western regions of Chinese displayed imbalance. There are seven tumor types for sperm preservation in the top incidence ten tumor types, including lymphoma, leukemia, nasopharyngeal carcinoma, sarcoma, thyroid cancer, and brain tumor. Moreover, nasopharyngeal carcinoma is a high incidence rate in China, which is related to high sperm preservation rate, different from other countries. The most percentage of males receiving sperm cryopreservation in the testicular cancers (15-39 years old) of China in 2020 was 5.55%, 1.29% in the lymphoma, and 0.39% in the leukemia. According to the type of cancer, a statistically significant lower pre-sperm density, total sperm output, and post-sperm density was observed in testicular cancers. It is worth noting that the prevalence of azoospermia 22.2% in leukemia patients attribute to urgent treatment before sperm cryopreservation. Disposition of cryopreserved sperm categories included continued storage (47.2%), discarded (9%), death (0.9%), and use (3.7%). CONCLUSION: This study provides the first comprehensive national statistical census and review of fertility preservation in male cancer patients with respect to trends, prevalence, and cancer types. The development of male cancer fertility preservation in China is imbalanced and percentage of males receiving sperm cryopreservation in the adolescent and young adult cancers was low. Sixteen human sperm banks from China analyze current problems and challenges, and then prioritize steps toward the achievement of the FP strategy framework for Healthy China 2030.


Assuntos
Criopreservação , Preservação da Fertilidade , Neoplasias , Preservação do Sêmen , Bancos de Esperma , Humanos , Masculino , Preservação da Fertilidade/métodos , China/epidemiologia , Criopreservação/métodos , Adulto , Preservação do Sêmen/métodos , Neoplasias/epidemiologia , Neoplasias/patologia , Adolescente , Espermatozoides , Estudos Retrospectivos , Análise do Sêmen , Infertilidade Masculina/epidemiologia , Adulto Jovem , População do Leste Asiático
6.
Environ Sci Technol ; 57(35): 13025-13035, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37608438

RESUMO

Exposure to fine particulate matter (PM < 2.5 µm in diameter [PM2.5]) may accelerate human sperm quality decline, although research on this association is limited. Our objective was to investigate the relationship between exposure to the chemical constituents of PM2.5 air pollution and decreased sperm quality and to further explore the exposure-response relationship. We conducted a multicenter population-based cohort study including 78,952 semen samples from 33,234 donors at 6 provincial human sperm banks (covering central, northern, southern, eastern, and southwestern parts of China) between 2014 and 2020. Daily exposure to PM2.5 chemical composition was estimated using a deep learning model integrating a density ground-based measure network at a 1 km resolution. Linear mixed models with subject- and center-specific intercepts were used to quantify the harmful impacts of PM2.5 constituents on semen quality and explore their exposure-response relationships. Per interquartile range (IQR) increase in PM2.5 exposure levels during spermatogenesis was significantly associated with decreased sperm concentration, progressive motility, and total motility. For PM2.5 constituents, per IQR increment in Cl- (ß: -0.02, 95% CI: [-0.03, -0.00]) and NO3- (ß: -0.05, 95% CI: [-0.08, -0.02]) exposure was negatively associated with sperm count, while NH4+ (ß: -0.03, 95% CI: [-0.06, -0.00]) was significantly linked to decreased progressive motility. These results suggest that exposure to PM2.5 chemical constituents may adversely affect human sperm quality, highlighting the urgent need to reduce PM2.5 exposure.


Assuntos
Análise do Sêmen , Sêmen , Masculino , Humanos , Estudos de Coortes , Contagem de Espermatozoides , Material Particulado
7.
Physiol Mol Biol Plants ; 29(6): 783-790, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37520815

RESUMO

Root systems anchor plants to the substrate in addition to transporting water and nutrients, playing a fundamental role in plant survival. The LAZY1 gene mediates gravity signal transduction and participates in root and shoot development and auxin flow in many plants. In this study, a regulator, LsLAZY1, was identified from Leymus secalinus based on previous transcriptome data. The conserved domain and evolutionary relationship were further analyzed comprehensively. The role of LsLAZY1 in root development was investigated by genetic transformation and associated gravity response and phototropism assay. Subcellular localization showed that LsLAZY1 was localized in the nucleus. LsLAZY1 overexpression in Arabidopsis thaliana (Col-0) increased the length of the primary roots (PRs) and the number of lateral roots (LRs) compared to Col-0. Furthermore, 35S:LsLAZY1 transgenic seedlings affected auxin transport and showed a stronger gravitational and phototropic responses. It also promoted auxin accumulation at the root tips. These results indicated that LsLAZY1 affects root development and auxin transport. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01326-4.

8.
Zhonghua Nan Ke Xue ; 29(2): 144-150, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-37847086

RESUMO

OBJECTIVE: To explore the feasibility of Ion Torrent PGM sequencing in detection of Y chromosome microdeletion. METHODS: We enrolled 87 infertility patients with non-obstructive azoospermia (NOA) in this study and analyzed their routine semen parameters, reproductive hormone levels and chromosomal karyotypes. We detected Y chromosome microdeletion in the patients by Ion Torrent PGM sequencing and multiplex PCR, and compared the detection rates between the two methods. RESULTS: Ion Torrent PGM sequencing achieved a significantly higher detection rate of Y chromosome microdeletion than multiplex PCR (49.4% vs 12.6%, P < 0.05). The cases of AZF deletion detected by Ion Torrent PGM sequencing included all those detected by multiplex PCR, and the deletion sites were completely consistent. In addition, 14 male infertility-related gene mutations were detected in 24 of the 87 patients, with a total positive rate of 27.59%. CONCLUSION: Ion Torrent PGM sequencing can significantly improve the detection rate of Y chromosome microdeletion in infertility patients with NOA, detect a variety of male infertility-related gene mutations, and therefore contribute to the diagnosis of azoospermia.


Assuntos
Azoospermia , Infertilidade Masculina , Oligospermia , Humanos , Masculino , Azoospermia/genética , Azoospermia/diagnóstico , Infertilidade Masculina/genética , Deleção Cromossômica , Aberrações dos Cromossomos Sexuais , Cromossomos Humanos Y/genética , Oligospermia/genética
9.
J Cell Physiol ; 237(12): 4477-4486, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36183380

RESUMO

Miro1, a mitochondrial Rho GTPase1, is a kind of mitochondrial outer membrane protein involved in the regulation of mitochondrial anterograde transport and its subcellular distribution. Mitochondria influence reproductive processes of mammals in some aspects. Mitochondria are important for oocyte maturation, fertilization and embryonic development. The purpose of this study was to evaluate whether Miro1 regulates mouse oocyte maturation by altering mitochondrial homeostasis. We showed that Miro1 was expressed in mouse oocyte at different maturation stages. Miro1 mainly distributed in the cytoplasm and around the spindle during oocyte maturation. Small interference RNA-mediated Miro1 depletion caused significantly abnormal distribution of mitochondria and endoplasmic reticulum as well as mitochondrial dysfunction, resulting in severely impaired germinal vesicle breakdown (GVBD) of mouse oocytes. For those oocytes which went through GVBD in the Miro1-depleted group, part of them were inhibited in meiotic prophase I stage with abnormal chromosome arrangement and scattered spindle length. Our results suggest that Miro1 is essential for maintaining the maturation potential of mouse oocyte.


Assuntos
Meiose , Mitocôndrias , Oócitos , Proteínas rho de Ligação ao GTP , Animais , Feminino , Camundongos , Gravidez , Homeostase , Mitocôndrias/fisiologia , Oócitos/fisiologia , Oogênese , Proteínas rho de Ligação ao GTP/fisiologia
10.
J Sep Sci ; 45(5): 1051-1058, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34984820

RESUMO

Ephedrae Herba is one of the most commonly used herbal medicines, and it has been shown that most of the clinical efficacy for cold and asthma is exerted by its alkaloidal components. A simple and sensitive high-performance liquid chromatography method was developed using a perfluorooctyl column for the simultaneous determination of five alkaloids (norephedrine, norpseudoephedrine, ephedrine, pseudoephedrine, and methylephedrine) in Ephedrae Herba. The mobile phase comprising acetonitrile and 15 mM ammonium trifluoroacetate was used to elute the targets in isocratic elution mode. The method was validated for linearity (R2  > 0.999), repeatability, intraday and interday precision, recoveries with trueness (93.87-110.99%), limits of detection (5.35-5.76 µg/mL), and limits of quantification (20 µg/mL). The quantitative results revealed that the developed method was precise and accurate. Then it was successfully applied to determine the difference in the contents of three batches of Ephedrae Herba from three pharmaceutical companies.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Efedrina/análise , Pseudoefedrina/análise
11.
J Cell Physiol ; 236(7): 5352-5361, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33586215

RESUMO

In vitro culture of follicles is a promising technology to generate large quantities of mature oocytes and it could offer a novel option of assisted reproductive technologies. Here we described a 2-dimensional follicular serum-free culture system with 3-dimensional effect that can make secondary follicles develop into antral follicles (78.52%), generating developmentally mature oocytes in vitro (66.45%). The oocytes in this serum-free system completed the first meiosis; spindle assembly and chromosome congression in most oocytes matured from follicular culture were normal. However, these oocytes showed significantly lower activation and embryonic development rates, and their ability to produce Ca2+ oscillations was also lower in response to parthenogenetic activation, after which a 2-cell embryonic developmental block occurred. Oocytes matured from follicular culture displayed increased abnormal mitochondrial distribution and increased reactive oxygen species levels when compared to in vivo matured oocytes. These data are important for understanding the reasons for reduced developmental potential of oocytes matured from follicular culture, and for further improving the cultivation system.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos , Folículo Ovariano , Animais , Núcleo Celular , Citoplasma , Feminino , Camundongos , Oócitos/fisiologia
12.
Opt Express ; 28(4): 4587-4593, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121692

RESUMO

This paper presents an InAs/InP quantum dash (QD) C-band passively mode-locked laser (MLL) with a channel spacing of 34.224 GHz. By using this QD-MLL we demonstrate an aggregate 5.376 Tbit/s PAM-4 data transmission capacity both for back-to-back (B2B) and over 25-km of standard single mode fiber (SSMF). This represents the first demonstration of QD-MLL acting as error-free operation at an aggregate data transmission capacity of 5.376 Tbit/s for some filtered individual channels. This finding highlights the viability for InAs/InP QD lasers to be used as a low-cost optical source for data center networks.

13.
Mol Cell ; 46(1): 7-17, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22387026

RESUMO

Histone modifications play important roles in regulating DNA-based biological processes. Of the modified sites, histone H3 lysine 56 (H3K56) is unique in that it lies within the globular core domain near the entry-exit sites of the nucleosomal DNA superhelix and its acetylation state in yeast is a marker for newly synthesized histones in transcription, DNA repair, and DNA replication. We now report the presence of H3K56 monomethylation (H3K56me1) in mammalian cells and find that the histone lysine methytransferase G9a/KMT1C is required for H3K56me1 both in vivo and in vitro. We also find that disruption of G9a or H3K56 impairs DNA replication. Furthermore, H3K56me1 associates with the replication processivity factor PCNA primarily in G1 phase of the cell cycle and, directly, in vitro. These results find H3K56me1 in mammals and indicate a role for H3K56me1 as a chromatin docking site for PCNA prior to its function in DNA replication.


Assuntos
Replicação do DNA/fisiologia , Fase G1/fisiologia , Histonas/metabolismo , Nucleossomos/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Células HEK293 , Células HeLa , Histonas/genética , Humanos , Lisina/genética , Lisina/metabolismo , Metilação , Nucleossomos/genética , Antígeno Nuclear de Célula em Proliferação/genética
14.
Genes Dev ; 26(21): 2443-55, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23124068

RESUMO

Yeast contains heterochromatin at telomeres and the silent mating-type loci (HML/HMR). Genes positioned within the telomeric heterochromatin of Saccharomyces cerevisiae switch stochastically between epigenetically bistable ON and OFF expression states. Important aspects of the mechanism of variegated gene expression, including the chromatin structure of the natural ON state and the mechanism by which it is maintained, are unknown. To address this issue, we developed approaches to select cells in the ON and OFF states. We found by chromatin immunoprecipitation (ChIP) that natural ON telomeres are associated with Rap1 binding and, surprisingly, also contain known characteristics of OFF telomeres, including significant amounts of Sir3 and H4K16 deacetylated nucleosomes. Moreover, we found that H3K79 methylation (H3K79me), H3K4me, and H3K36me, which are depleted from OFF telomeres, are enriched at ON telomeres. We demonstrate in vitro that H3K79me, but not H3K4me or H3K36me, disrupts transcriptional silencing. Importantly, H3K79me does not significantly reduce Sir complex binding in vivo or in vitro. Finally, we show that maintenance of H3K79me at ON telomeres is dependent on transcription. Therefore, although Sir proteins are required for silencing, we propose that epigenetic variegation of telomeric gene expression is due to the bistable enrichment/depletion of H3K79me and not the fluctuation in the amount of Sir protein binding to nucleosomes.


Assuntos
Epigenômica , Regulação Fúngica da Expressão Gênica , Variação Genética , Heterocromatina/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telômero/genética , Meios de Cultura , Metilação de DNA , Citometria de Fluxo , Inativação Gênica , Histonas/metabolismo , Ligação Proteica , Proteínas de Saccharomyces cerevisiae/metabolismo
15.
Opt Express ; 27(24): 35368-35375, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878707

RESUMO

We have developed and experimentally demonstrated a novel monolithic InAs/InP quantum-dash dual-wavelength distributed feedback (QD DW-DFB) C-band laser as a compact optical beat source to generate millimeter-wave (MMW) signals. The device uses a common gain medium in a single cavity structure for simultaneous correlated and stable dual-mode lasing in the 1550-nm wavelength range. A record narrow optical linewidth down to 15.83 kHz and average relative intensity noise (RIN) as low as -158.3 dB/Hz from 10 MHz to 20 GHz are experimentally demonstrated for the two optical modes generated by the laser. As a result, the beat note between these two lasing modes generates spectrally pure MMW signals between 46 GHz and 48 GHz. Such an efficient, coherent, and compact optical source is extremely attractive for applications in MMW systems, such as Radar and fiber-wireless integrated fronthaul for 5G and beyond.

16.
Zhonghua Nan Ke Xue ; 25(8): 681-689, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-32227709

RESUMO

OBJECTIVE: To explore the pathways of development and maturation of the testis tissue in mice with spermatogenic dysfunction in vitro. METHODS: Sixty-eight 8-week-old BALB/c male mice were randomly divided into four groups of equal number, normal control, Sertoli cell only syndrome (SCOS), severe hypo-spermatogenesis (H-S1), and mild hypo-spermatogenesis (H-S2), and the models were established in the latter three groups by intraperitoneal injection of busulfan at 40 mg/kg for 4, 6 and 8 weeks, respectively. The testis tissues of the mice were cultured with the agarose gel method in vitro till the 4th week, followed by determination of the expressions of the marker proteins STRA8 at meiotic initiation, SCP3 during meiosis, and TNP1 after meiosis by immunohistochemistry. The development and maturation of the germ cells during the in vitro culture were evaluated, and their apoptosis detected by TUNEL. RESULTS: The more severe the testicular tissue injury, the lower the expression of the STRA8 protein in the SCOS, H-S1 and H-S2 groups as compared with the normal control before in vitro culture on agarose gel (P < 0.05), and the STRA8 expression was significantly upregulated in the former three groups after 4 weeks of culturing (P < 0.05). The expression of SCP3 was the lowest in the SCOS but the highest in the H-S2 group before culturing (P < 0.05), and was not as high as that in the control, though increased after 4 weeks of culturing. TNP1 was positively expressed in all the mice of the control, some individuals of the H-S1 and H-S2 groups (P< 0.05), but not in the SCOS group at 4 weeks. The apoptosis of germ cells was significantly increased in the SCOS but decreased in the H-S groups compared with that in the normal control after 4 weeks of culturing (P< 0.05). CONCLUSIONS: In vitro culture on agarose gel induces the meiosis of the testis tissue in BALB/c mice with spermatogenic dysfunction, and the effect is even better in those with mild spermatogenic dysfunction.


Assuntos
Técnicas de Cultura de Órgãos , Síndrome de Células de Sertoli/fisiopatologia , Espermatogênese , Testículo/fisiopatologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Apoptose , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Masculino , Meiose , Camundongos , Camundongos Endogâmicos BALB C
17.
Mol Cell ; 33(4): 417-27, 2009 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-19250903

RESUMO

Lysine 56 acetylation in the helical core of histone H3 opens yeast chromatin and enables histone gene transcription, DNA replication, and DNA repair and prevents epigenetic silencing. While K56Ac is globally abundant in yeast and flies, its presence has been uncertain in mammals. We show here using mass spectrometry and genome-wide analyses that K56Ac is present in human embryonic stem cells (hESCs), overlapping strongly at active and inactive promoters with the binding of the key regulators of pluripotency, NANOG, SOX2, and OCT4. This includes also the canonical histone gene promoters and those for the hESC-specific microRNAs. K56Ac then relocates to developmental genes upon cellular differentiation. Thus the K56Ac state more accurately reflects the epigenetic differences between hESCs and somatic cells than other active histone marks such as H3 K4 trimethylation and K9 acetylation. These results suggest that K56Ac is involved in the human core transcriptional network of pluripotency.


Assuntos
Células-Tronco Embrionárias/metabolismo , Redes Reguladoras de Genes , Histonas/metabolismo , Lisina/metabolismo , Acetilação , Animais , Imunoprecipitação da Cromatina , Células-Tronco Embrionárias/citologia , Genoma Humano , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Lisina/química , Camundongos , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Processamento de Proteína Pós-Traducional/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
18.
BMC Med Genet ; 17(1): 91, 2016 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-27912749

RESUMO

BACKGROUND: Congenital contractural arachnodactyly (CCA) is an autosomal dominant rare genetic disease, estimated to be less than 1 in 10,000 worldwide. People with this condition often have permanently bent joints (contractures), like bent fingers and toes (camptodactyly). CASE PRESENTATION: In this study, we investigated the genetic aetiology of CCA in a four-generation Chinese family. The blood samples were collected from 22 living members of the family in the Yangquan County, Shanxi Province, China. Of those, eight individuals across 3 generations have CCA. Whole exome sequencing (WES) identified a missense mutation involving a T-to-G transition at position 3229 (c.3229 T > G) in exon 25 of the FBN2 gene, resulting in a Cys 1077 to Gly change (p.C1077G). This previously unreported mutation was found in all 8 affected individuals, but absent in 14 unaffected family members. SIFT/PolyPhen prediction and protein conservation analysis suggest that this novel mutation is pathogenic. Our study extended causative mutation spectrum of FBN2 gene in CCA patients. CONCLUSIONS: This study has identified a novel missense mutation in FBN2 gene (p.C1077G) resulting in CCA in a family of China.


Assuntos
Aracnodactilia/genética , Povo Asiático/genética , Contratura/genética , Fibrilina-2/genética , Alelos , Sequência de Aminoácidos , Animais , Aracnodactilia/diagnóstico , Sequência de Bases , China , Contratura/diagnóstico , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Análise Mutacional de DNA , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Linhagem , Alinhamento de Sequência
19.
Proc Natl Acad Sci U S A ; 110(28): 11493-8, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23798425

RESUMO

The presence of acetylated histone H3K56 (H3K56ac) in human ES cells (ESCs) correlates positively with the binding of Nanog, Sox2, and Oct4 (NSO) transcription factors at their target gene promoters. However, the function of H3K56ac there has been unclear. We now report that Oct4 interacts with H3K56ac in mouse ESC nuclear extracts and that perturbing H3K56 acetylation decreases Oct4-H3 binding. This interaction is likely to be direct because it can be recapitulated in vitro in an H3K56ac-dependent manner and is functionally important because H3K56ac combines with NSO factors in chromatin immunoprecipitation sequencing to mark the regions associated with pluripotency better than NSO alone. Moreover, reducing H3K56ac by short hairpin Asf1a decreases expression of pluripotency-related markers and increases expression of differentiation-related ones. Therefore, our data suggest that H3K56ac plays a central role in binding to Oct4 to promote the pluripotency of ESCs.


Assuntos
Células-Tronco Embrionárias/citologia , Histonas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Acetilação , Animais , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Camundongos , Ligação Proteica
20.
BMC Pregnancy Childbirth ; 15: 343, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26694165

RESUMO

BACKGROUND: Few studies on cluster-based synthetic effects of multiple risk factors for birth defects have been reported. The present study aimed to identify maternal exposure clusters, explore the association between clusters of risk factors and birth defects, and further screen women with high risk for birth defects among expectant mothers. METHODS: Data were drawn from a large-scale, retrospective epidemiological survey of birth defects from 2006 to 2008 in six counties of Shanxi Province, China, using a three-level stratified random cluster sampling technique. Overall risk factors were extracted using eight synthetic variables summed and examined as a total risk factor score: maternal delivery age, genetic factors, medical history, nutrition and folic acid deficiency, maternal illness in pregnancy, drug use in pregnancy, environmental risk factors in pregnancy, and unhealthy maternal lifestyle in pregnancy. Latent class cluster analysis was used to identify maternal exposure clusters based on these synthetic variables. Adjusted odds ratios (AOR) were used to explore associations between clusters and birth defects, after adjusting for confounding variables using logistic regression. RESULTS: Three latent maternal exposure clusters were identified: a high-risk (6.15%), a moderate-risk (22.39%), and a low-risk (71.46%) cluster. The prevalence of birth defects was 14.08%, 0.85%, and 0.52% for the high-, middle- and low-risk clusters respectively. After adjusting for maternal demographic variables, women in the high-risk cluster were nearly 31 times (AOR: 30.61, 95% CI: [24.87, 37.67]) more likely to have an infant with birth defects than low-risk women. CONCLUSIONS: A high-risk group of mothers in an area with a high risk for birth defects were screened in our study. Targeted interventions should be conducted with women of reproductive age to improve neonatal birth outcomes in areas with a high risk of birth defects.


Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/etiologia , Deficiência de Ácido Fólico , Idade Materna , Exposição Materna , Complicações na Gravidez , Adulto , China , Análise por Conglomerados , Feminino , Humanos , Lactente , Estilo de Vida , Modelos Logísticos , Programas de Rastreamento , Razão de Chances , Gravidez , Estudos Retrospectivos , Fatores de Risco
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