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1.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37369639

RESUMO

DNA methylation plays a crucial role in transcriptional regulation. Reduced representation bisulfite sequencing (RRBS) is a technique of increasing use for analyzing genome-wide methylation profiles. Many computational tools such as Metilene, MethylKit, BiSeq and DMRfinder have been developed to use RRBS data for the detection of the differentially methylated regions (DMRs) potentially involved in epigenetic regulations of gene expression. For DMR detection tools, as for countless other medical applications, P-values and their adjustments are among the most standard reporting statistics used to assess the statistical significance of biological findings. However, P-values are coming under increasing criticism relating to their questionable accuracy and relatively high levels of false positive or negative indications. Here, we propose a method to calculate E-values, as likelihood ratios falling into the null hypothesis over the entire parameter space, for DMR detection in RRBS data. We also provide the R package 'metevalue' as a user-friendly interface to implement E-value calculations into various DMR detection tools. To evaluate the performance of E-values, we generated various RRBS benchmarking datasets using our simulator 'RRBSsim' with eight samples in each experimental group. Our comprehensive benchmarking analyses showed that using E-values not only significantly improved accuracy, area under ROC curve and power, over that of P-values or adjusted P-values, but also reduced false discovery rates and type I errors. In applications using real RRBS data of CRL rats and a clinical trial on low-salt diet, the use of E-values detected biologically more relevant DMRs and also improved the negative association between DNA methylation and gene expression.


Assuntos
Metilação de DNA , Animais , Ratos , Análise de Sequência de DNA/métodos , Curva ROC , Ilhas de CpG
2.
Lab Invest ; 104(5): 102036, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38408704

RESUMO

Arterioles are key determinants of the total peripheral vascular resistance, which, in turn, is a key determinant of arterial blood pressure. However, the amount of protein available from one isolated human arteriole may be less than 5 µg, making proteomic analysis challenging. In addition, obtaining human arterioles requires manual dissection of unfrozen clinical specimens. This limits its feasibility, especially for powerful multicenter clinical studies in which clinical specimens need to be shipped overnight to a research laboratory for arteriole isolation. We performed a study to address low-input, test overnight tissue storage and develop a reference human arteriolar proteomic profile. In tandem mass tag proteomics, use of a booster channel consisting of human induced pluripotent stem cell-derived endothelial and vascular smooth muscle cells (1:5 ratio) increased the number of proteins detected in a human arteriole segment with a false discovery rate of <0.01 from 1051 to more than 3000. The correlation coefficient of proteomic profile was similar between replicate arterioles isolated freshly, following cold storage, or before and after the cold storage (1-way analysis of variance; P = .60). We built a human arteriolar proteomic profile consisting of 3832 proteins based on the analysis of 12 arteriole samples from 3 subjects. Of 1945 blood pressure-relevant proteins that we curated, 476 (12.5%) were detected in the arteriolar proteome, which was a significant overrepresentation (χ2 test; P < .05). These findings demonstrate that proteomic analysis is feasible with arterioles isolated from human adipose tissue following cold overnight storage and provide a reference human arteriolar proteome profile highly valuable for studies of arteriole-related traits.


Assuntos
Tecido Adiposo , Proteômica , Humanos , Arteríolas/metabolismo , Proteômica/métodos , Tecido Adiposo/metabolismo , Tecido Adiposo/irrigação sanguínea , Proteoma/metabolismo , Proteoma/análise , Feminino , Masculino , Adulto , Pessoa de Meia-Idade
3.
Arch Gynecol Obstet ; 310(2): 933-942, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38814455

RESUMO

OBJECTIVE: To explore the association between the concentration of maternal serum biomarkers and the risk of fetal carrying chromosome copy number variants (CNVs). METHODS: Pregnant women identified as high risk in the second-trimester serological triple screening and underwent traditional amniotic fluid karyotype analysis, along with comparative genomic hybridization array (aCGH)/copy number variation sequencing (CNV-seq), were included in the study. We divided the concentration of serum biomarkers, free beta-human chorionic gonadotropin (fß-hCG), alpha fetoprotein (AFP) and unconjugated estriol (uE3), into three levels: abnormally low, normal and abnormally high. The prevalence of abnormally low, normal and abnormally high serum fß-hCG, AFP and uE3 levels in pregnant women with aberrant aCGH/CNV-seq results and normal controls was calculated. RESULTS: Among the 2877 cases with high risk in the second-trimester serological triple screening, there were 98 chromosome abnormalities revealed by karyotype analysis, while 209 abnormalities were detected by aCGH/CNVseq (P<0.001) . The carrying rate of aberrant CNVs increased significantly when the maternal serum uE3 level was less than 0.4 multiple of median (MoM) of corresponding gestational weeks compared to normal controls, while the carrying rate of aberrant CNVs decreased significantly when the maternal serum fß-hCG level was greater than 2.5 MoM compared to normal controls. No significant difference was found in the AFP group. CONCLUSION: Low serum uE3 level (<0.4 MoM) was associated with an increased risk of aberrant CNVs.


Assuntos
Biomarcadores , Gonadotropina Coriônica Humana Subunidade beta , Variações do Número de Cópias de DNA , alfa-Fetoproteínas , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Adulto , Biomarcadores/sangue , Gonadotropina Coriônica Humana Subunidade beta/sangue , alfa-Fetoproteínas/análise , alfa-Fetoproteínas/metabolismo , Segundo Trimestre da Gravidez/sangue , Estriol/sangue , Hibridização Genômica Comparativa , Aberrações Cromossômicas , Cariotipagem , Diagnóstico Pré-Natal/métodos , Testes para Triagem do Soro Materno
4.
Molecules ; 29(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930971

RESUMO

The direct 1,6-nucleophilic difluoromethylation, trifluoromethylation, and difluoroalkylation of para-quinone methides (p-QMs) with Me3SiRf (Rf = CF2H, CF3, CF2CF3, CF2COOEt, and CF2SPh) under mild conditions are described. Although Me3SiCF2H shows lower reactivity than Me3SiCF3, it can react with p-QMs promoted by CsF/18-Crown-6 to give structurally diverse difluoromethyl products in good yields. The products can then be further converted into fluoroalkylated para-quinone methides and α-fluoroalkylated diarylmethanes.

5.
BMC Genomics ; 24(1): 371, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37394518

RESUMO

BACKGROUND: A common feature of single-cell RNA-seq (scRNA-seq) data is that the number of cells in a cell cluster may vary widely, ranging from a few dozen to several thousand. It is not clear whether scRNA-seq data from a small number of cells allow robust identification of differentially expressed genes (DEGs) with various characteristics. RESULTS: We addressed this question by performing scRNA-seq and poly(A)-dependent bulk RNA-seq in comparable aliquots of human induced pluripotent stem cells-derived, purified vascular endothelial and smooth muscle cells. We found that scRNA-seq data needed to have 2,000 or more cells in a cluster to identify the majority of DEGs that would show modest differences in a bulk RNA-seq analysis. On the other hand, clusters with as few as 50-100 cells may be sufficient for identifying the majority of DEGs that would have extremely small p values or transcript abundance greater than a few hundred transcripts per million in a bulk RNA-seq analysis. CONCLUSION: Findings of the current study provide a quantitative reference for designing studies that aim for identifying DEGs for specific cell clusters using scRNA-seq data and for interpreting results of such studies.


Assuntos
Perfilação da Expressão Gênica , Células-Tronco Pluripotentes Induzidas , Humanos , Perfilação da Expressão Gênica/métodos , Análise da Expressão Gênica de Célula Única , RNA-Seq , Análise de Célula Única/métodos , Análise de Sequência de RNA/métodos
6.
Mol Ther ; 30(11): 3462-3476, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35965413

RESUMO

MicroRNA miR-29 promotes endothelial function in human arterioles in part by targeting LYPLA1 and increasing nitric oxide production. In addition, miR-29 is a master inhibitor of extracellular matrix gene expression, which may attenuate fibrosis but could also weaken tissue structure. The goal of this study was to test whether miR-29 could be developed as an effective, broad-acting, and safe therapeutic. Substantial accumulation of miR-29b and effective knockdown of Lypla1 in several mouse tissues were achieved using a chitosan-packaged, chemically modified miR-29b mimic (miR-29b-CH-NP) injected systemically at 200 µg/kg body weight. miR-29b-CH-NP, injected once every 3 days, significantly attenuated angiotensin II-induced hypertension. In db/db mice, miR-29b-CH-NP treatment for 12 weeks decreased cardiac and renal fibrosis and urinary albuminuria. In uninephrectomized db/db mice, miR-29b-CH-NP treatment for 20 weeks significantly improved myocardial performance index and attenuated proteinuria. miR-29b-CH-NP did not worsen abdominal aortic aneurysm in ApoE knockout mice treated with angiotensin II. miR-29b-CH-NP caused aortic root fibrotic cap thinning in ApoE knockout mice fed a high-cholesterol and high-fat diet but did not worsen the necrotic zone or mortality. In conclusion, systemic delivery of low-dose miR-29b-CH-NP is an effective therapeutic for several forms of cardiovascular and renal disease in mice.


Assuntos
Quitosana , Complicações do Diabetes , Diabetes Mellitus , Hipertensão , MicroRNAs , Camundongos , Humanos , Animais , Angiotensina II/efeitos adversos , MicroRNAs/genética , MicroRNAs/metabolismo , Camundongos Knockout para ApoE , Modelos Animais de Doenças , Hipertensão/genética , Hipertensão/terapia , Fibrose , Camundongos Endogâmicos , Tioléster Hidrolases
7.
Kidney Int ; 101(4): 766-778, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35114200

RESUMO

Pathological heterogeneity is common in clinical tissue specimens and complicates the interpretation of molecular data obtained from the specimen. As a typical example, a kidney biopsy specimen often contains glomeruli and tubulointerstitial regions with different levels of histological injury, including some that are histologically normal. We reasoned that the molecular profiles of kidney tissue regions with specific histological injury scores could provide new insights into kidney injury progression. Therefore, we developed a strategy to perform small RNA deep sequencing analysis for individually scored glomerular and tubulointerstitial regions in formalin-fixed, paraffin-embedded kidney needle biopsies. This approach was applied to study focal segmental glomerulosclerosis (FSGS), the leading cause of nephrotic syndrome in adults. Large numbers of small RNAs, including microRNAs, 3'-tRFs, 5'-tRFs, and mitochondrial tRFs, were differentially expressed between histologically indistinguishable tissue regions from patients with FSGS and matched healthy controls. A majority of tRFs were upregulated in FSGS. Several small RNAs were differentially expressed between tissue regions with different histological scores in FSGS. Notably, with increasing levels of histological damage, miR-21-5p was upregulated progressively and miR-192-5p was downregulated progressively in glomerular and tubulointerstitial regions, respectively. This study marks the first genome scale molecular profiling conducted in histologically characterized glomerular and tubulointerstitial regions. Thus, substantial molecular changes in histologically normal kidney regions in FSGS might contribute to initiating tissue injury or represent compensatory mechanisms. In addition, several small RNAs might contribute to subsequent progression of glomerular and tubulointerstitial injury, and histologically mapping small RNA profiles may be applied to analyze tissue specimens in any disease.


Assuntos
Glomerulosclerose Segmentar e Focal , MicroRNAs , Síndrome Nefrótica , Adulto , Feminino , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Rim/patologia , Glomérulos Renais/patologia , Masculino , MicroRNAs/genética , Síndrome Nefrótica/patologia
8.
Curr Oncol Rep ; 23(7): 77, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33937943

RESUMO

PURPOSE OF REVIEW: Cardiovascular toxicity is a leading cause of mortality among cancer survivors and has become increasingly prevalent due to improved cancer survival rates. In this review, we synthesize evidence illustrating how common cancer therapeutic agents, such as anthracyclines, human epidermal growth factors receptors (HER2) monoclonal antibodies, and tyrosine kinase inhibitors (TKIs), have been evaluated in cardiomyocytes (CMs) derived from human-induced pluripotent stem cells (hiPSCs) to understand the underlying mechanisms of cardiovascular toxicity. We place this in the context of precision cardio-oncology, an emerging concept for personalizing the prevention and management of cardiovascular toxicities from cancer therapies, accounting for each individual patient's unique factors. We outline steps that will need to be addressed by multidisciplinary teams of cardiologists and oncologists in partnership with regulators to implement future applications of hiPSCs in precision cardio-oncology. RECENT FINDINGS: Current prevention of cardiovascular toxicity involves routine screenings and management of modifiable risk factors for cancer patients, as well as the initiation of cardioprotective medications. Despite recent advancements in precision cardio-oncology, knowledge gaps remain and limit our ability to appropriately predict with precision which patients will develop cardiovascular toxicity. Investigations using patient-specific CMs facilitate pharmacological discovery, mechanistic toxicity studies, and the identification of cardioprotective pathways. Studies with hiPSCs demonstrate that patients with comorbidities have more frequent adverse responses, compared to their counterparts without cardiac disease. Further studies utilizing hiPSC modeling should be considered, to evaluate the impact and mitigation of known cardiovascular risk factors, including blood pressure, body mass index (BMI), smoking status, diabetes, and physical activity in their role in cardiovascular toxicity after cancer therapy. Future real-world applications will depend on understanding the current use of hiPSC modeling in order for oncologists and cardiologists together to inform their potential to improve our clinical collaborative practice in cardio-oncology. When applying such in vitro characterization, it is hypothesized that a safety score can be assigned to each individual to determine who has a greater probability of developing cardiovascular toxicity. Using hiPSCs to create personalized models and ultimately evaluate the cardiovascular toxicity of individuals' treatments may one day lead to more patient-specific treatment plans in precision cardio-oncology while reducing cardiovascular disease (CVD) morbidity and mortality.


Assuntos
Doenças Cardiovasculares/etiologia , Células-Tronco Pluripotentes Induzidas/citologia , Neoplasias/complicações , Medicina de Precisão , Antraciclinas/toxicidade , Cardiotoxicidade , Doenças Cardiovasculares/prevenção & controle , Diferenciação Celular , Reprogramação Celular , Humanos , Receptor ErbB-2/antagonistas & inibidores , Fatores de Risco
9.
J Am Soc Nephrol ; 31(7): 1539-1554, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32487559

RESUMO

BACKGROUND: Aberrant microRNA (miRNA) expression affects biologic processes and downstream genes that are crucial to CKD initiation or progression. The miRNA miR-204-5p is highly expressed in the kidney but whether miR-204-5p plays any role in the development of chronic renal injury is unknown. METHODS: We used real-time PCR to determine levels of miR-204 in human kidney biopsies and animal models. We generated Mir204 knockout mice and used locked nucleic acid-modified anti-miR to knock down miR-204-5p in mice and rats. We used a number of physiologic, histologic, and molecular techniques to analyze the potential role of miR-204-5p in three models of renal injury. RESULTS: Kidneys of patients with hypertension, hypertensive nephrosclerosis, or diabetic nephropathy exhibited a significant decrease in miR-204-5p compared with controls. Dahl salt-sensitive rats displayed lower levels of renal miR-204-5p compared with partially protected congenic SS.13BN26 rats. Administering anti-miR-204-5p to SS.13BN26 rats exacerbated interlobular artery thickening and renal interstitial fibrosis. In a mouse model of hypertensive renal injury induced by uninephrectomy, angiotensin II, and a high-salt diet, Mir204 gene knockout significantly exacerbated albuminuria, renal interstitial fibrosis, and interlobular artery thickening, despite attenuation of hypertension. In diabetic db/db mice, administering anti-miR-204-5p exacerbated albuminuria and cortical fibrosis without influencing blood glucose levels. In all three models, inhibiting miR-204-5p or deleting Mir204 led to upregulation of protein tyrosine phosphatase SHP2, a target gene of miR-204-5p, and increased phosphorylation of signal transducer and activator of transcription 3, or STAT3, which is an injury-promoting effector of SHP2. CONCLUSIONS: These findings indicate that the highly expressed miR-204-5p plays a prominent role in safeguarding the kidneys against common causes of chronic renal injury.


Assuntos
Nefropatias Diabéticas/metabolismo , Hipertensão/metabolismo , Rim/metabolismo , Rim/patologia , MicroRNAs/metabolismo , Nefroesclerose/metabolismo , Adulto , Albuminúria/genética , Animais , Artérias/patologia , Pressão Sanguínea/efeitos dos fármacos , Nefropatias Diabéticas/patologia , Feminino , Fibrose , Técnicas de Silenciamento de Genes , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Nefroesclerose/etiologia , Nefroesclerose/patologia , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Cloreto de Sódio na Dieta/administração & dosagem , Regulação para Cima
10.
Genomics ; 112(6): 4567-4576, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32712292

RESUMO

DNA methylation plays a vital role in transcription regulation. Reduced representation bisulfite sequencing (RRBS) is becoming common for analyzing genome-wide methylation profiles at the single nucleotide level. A major goal of RRBS studies is to detect differentially methylated regions (DMRs) between different biological conditions. The previous tools to predict DMRs lack consistency. Here, we simulated RRBS datasets with significant attributes of real sequencing data under a wide range of scenarios, and systematically evaluated seven DMR detection tools in terms of type I error rate, precision/recall (PR), and area under ROC curve (AUC) using different methylation levels, sequencing coverage depth, length of DMRs, read length, and sample sizes. DMRfinder, methylSig, and methylKit were our preferred tools for RRBS data analysis, in terms of their AUC and PR curves. Our comparison highlights the different applicability of DMR detection tools and provides information to guide researchers towards the advancement of sequence-based DMR analysis.


Assuntos
Metilação de DNA , Análise de Sequência de DNA , Software , Humanos , Neoplasias/genética , Sulfitos
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(6): 557-560, 2021 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-34096025

RESUMO

OBJECTIVE: To carry out genetic testing for a Chinese patient with X-linked hypohidrotic ectodermal dysplasia (XLHED) and explore its genotype-phenotype correlation. METHODS: Clinical data of the patient was collected. Peripheral blood samples were taken from the patient, his parents and 100 unrelated healthy controls. Genetic variants were detected by using next-generation sequencing using a skin-disease panel through targeted capture and next generation sequencing. Candidate variant was verified by Sanger sequencing. All literature related to genetic testing of XLHED patients in China was searched in the database, and the genotypes and phenotypes of patients in the literature and the correlation between them were statistically analyzed. RESULTS: A novel splice site variant c.655_689del was detected in the patient but not among his parents and the 100 unrelated healthy controls. So far 61 variants of the EDA gene have been identified among Chinese patients with XLHED, which suggested certain degree of genotype-phenotype correlation. CONCLUSION: A novel c.655_689del variant has been identified in the EDA gene, which has expanded the spectrum of EDA gene variant and facilitated delineation of the genotype-phenotype correlation of XLHED.


Assuntos
Displasia Ectodérmica Anidrótica Tipo 1 , Criança , China , Displasia Ectodérmica Anidrótica Tipo 1/genética , Ectodisplasinas/genética , Testes Genéticos , Genótipo , Humanos , Fenótipo
12.
Kidney Int ; 98(2): 275-277, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32709285

RESUMO

microRNAs play prominent regulatory roles by inducing target mRNA degradation or translational repression. Several studies have highlighted the power of microRNAs as biomarkers and potential mechanistic mediators of human kidney disease. Small RNA deep sequencing libraries can be generated from minute amounts of formalin-fixed paraffin-embedded tissues including specific tissue regions. Such analyses have unique advantages and may complement analyses of fresh kidney specimens to advance tissue functional genomics-based precision medicine for human kidney disease.


Assuntos
Nefropatias , MicroRNAs , Formaldeído , Humanos , Nefropatias/genética , MicroRNAs/genética , Inclusão em Parafina , Fixação de Tecidos
14.
RNA Biol ; 17(8): 1081-1091, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32597311

RESUMO

Transfer RNA-derived fragments (tRFs) are a new class of small non-coding RNAs whose biological roles in cancers are not well understood. Emerging evidence suggests that tRFs are involved in gene regulation at multiple levels. In this study, we constructed an integrative database, OncotRF (http://bioinformatics.zju.edu.cn/OncotRF), for in silico exploration of tRF functions, and identification of diagnostic and prognostic biomarkers in cancers. The database contains an analysis pipeline for tRF identification and characterization, analysis results of 11,211 small RNA sequencing samples and 8,776 RNA sequencing samples, and clinicopathologic annotation data from The Cancer Genome Atlas (TCGA). The results include: tRF identification and quantification across 33 cancers, abnormally expressed tRFs and genes, tRF-gene correlations, tRF-gene networks, survival analyses, and tRF-related functional enrichment analyses. Users are also able to identify differentially expressed tRFs, predict their functions, and assess the relevance of the tRF expression levels to the clinical outcome according to user-defined groups. Additionally, an online Kaplan-Meier plotter is available in OncotRF for plotting survival curves according to user-defined groups. OncotRF will be a valuable online database and functional annotation tool for researchers studying the roles, functions, and mechanisms of tRFs in human cancers.


Assuntos
Biologia Computacional/métodos , Neoplasias/genética , RNA de Transferência/genética , RNA não Traduzido/genética , Software , Biomarcadores , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Humanos , Navegador
16.
J Biol Chem ; 293(36): 14080-14088, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30006350

RESUMO

Targeting mRNAs via seed region pairing is the canonical mechanism by which microRNAs (miRNAs) regulate cellular functions and disease processes. Emerging evidence suggests miRNAs might also act through other mechanisms. miRNA isomers that contain identical seed region sequences, such as miR-29a and miR-29b, provide naturally occurring, informative models for identifying those miRNA effects that are independent of seed region pairing. miR-29a and miR-29b are both expressed in HeLa cells, and miR-29b has been reported to localize to the nucleus in early mitosis because of unique nucleotide sequences on its 3' end. Here, we sought to better understand the mechanism of miR-29b nuclear localization and its function in cell division. We hypothesized that its nuclear localization may be facilitated by protein-miRNA interactions unique to miR-29b. Specific blockade of miR-29b resulted in striking nuclear irregularities not observed following miR-29a blockade. We also observed that miR-29b, but not miR-29a, is enriched in the nucleus and perinuclear clusters during mitosis. Targeted proteomic analysis of affinity-purified samples identified several proteins interacting with synthetic oligonucleotides mimicking miR-29b, but these proteins did not interact with miR-29a. One of these proteins, ADP/ATP translocase 2 (ANT2), known to be involved in mitotic spindle formation, colocalized with miR-29b in perinuclear clusters independently of Argonaute 2. Of note, ANT2 knockdown resulted in nuclear irregularities similar to those observed following miR-29b blockade and prevented nuclear uptake of endogenous miR-29b. Our findings reveal that miR-29 regulates nuclear morphology during mitosis and that this critical function is unique to the miR-29b isoform.


Assuntos
Transporte Ativo do Núcleo Celular , MicroRNAs/fisiologia , Translocador 2 do Nucleotídeo Adenina/análise , Divisão Celular , Forma do Núcleo Celular , Células HeLa , Humanos , Isomerismo , MicroRNAs/metabolismo , Mitose , Proteômica
17.
BMC Dev Biol ; 19(1): 16, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286885

RESUMO

BACKGROUND: The Tet protein family (Tet1, Tet2, and Tet3) regulate DNA methylation through conversion of 5-methylcytosine to 5-hydroxymethylcytosine which can ultimately result in DNA demethylation and play a critical role during early mammalian development and pluripotency. While multiple groups have generated knockouts combining loss of different Tet proteins in murine embryonic stem cells (ESCs), differences in genetic background and approaches has made it difficult to directly compare results and discern the direct mechanism by which Tet proteins regulate the transcriptome. To address this concern, we utilized genomic editing in an isogenic pluripotent background which permitted a quantitative, flow-cytometry based measurement of pluripotency in combination with genome-wide assessment of gene expression and DNA methylation changes. Our ultimate goal was to generate a resource of large-scale datasets to permit hypothesis-generating experiments. RESULTS: We demonstrate a quantitative disparity in the differentiation ability among Tet protein deletions, with Tet2 single knockout exhibiting the most severe defect, while loss of Tet1 alone or combinations of Tet genes showed a quantitatively intermediate phenotype. Using a combination of transcriptomic and epigenomic approaches we demonstrate an increase in DNA hypermethylation and a divergence of transcriptional profiles in pluripotency among Tet deletions, with loss of Tet2 having the most profound effect in undifferentiated ESCs. CONCLUSIONS: We conclude that loss of Tet2 has the most dramatic effect both on the phenotype of ESCs and the transcriptome compared to other genotypes. While loss of Tet proteins increased DNA hypermethylation, especially in gene promoters, these changes in DNA methylation did not correlate with gene expression changes. Thus, while loss of different Tet proteins alters DNA methylation, this change does not appear to be directly responsible for transcriptome changes. Thus, loss of Tet proteins likely regulates the transcriptome epigenetically both through altering 5mC but also through additional mechanisms. Nonetheless, the transcriptome changes in pluripotent Tet2-/- ESCs compared to wild-type implies that the disparities in differentiation can be partially attributed to baseline alterations in gene expression.


Assuntos
Metilação de DNA/genética , Proteínas de Ligação a DNA/genética , Células-Tronco Embrionárias/citologia , Proteínas Proto-Oncogênicas/genética , Animais , Sistemas CRISPR-Cas/genética , Diferenciação Celular/genética , Dioxigenases , Edição de Genes , Regulação da Expressão Gênica no Desenvolvimento/genética , Camundongos , Camundongos Knockout
18.
Bioinformatics ; 34(16): 2715-2723, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29579198

RESUMO

Motivation: The rapid development of next-generation sequencing technology provides an opportunity to study genome-wide DNA methylation at single-base resolution. However, depletion of unmethylated cytosines brings challenges for aligning bisulfite-converted sequencing reads to a large reference. Software tools for aligning methylation reads have not yet been comprehensively evaluated, especially for the widely used reduced representation bisulfite sequencing (RRBS) that involves enrichment for CpG islands (CGIs). Results: We specially developed a simulator, RRBSsim, for benchmarking analysis of RRBS data. We performed extensive comparison of seven mapping algorithms for methylation analysis in both real and simulated RRBS data. Eighteen lung tumors and matched adjacent tissues were sequenced by the RRBS protocols. Our empirical evaluation found that methylation results were less consistent between software tools for CpG sites with low sequencing depth, medium methylation level, on CGI shores or gene body. These observations were further confirmed by simulations that indicated software tools generally had lower recall of detecting these vulnerable CpG sites and lower precision of estimating methylation levels in these CpG sites. Among the software tools tested, bwa-meth and BS-Seeker2 (bowtie2) are currently our preferred aligners for RRBS data in terms of recall, precision and speed. Existing aligners cannot efficiently handle moderately methylated CpG sites and those CpG sites on CGI shores or gene body. Interpretation of methylation results from these vulnerable CpG sites should be treated with caution. Our study reveals several important features inherent in methylation data, and RRBSsim provides guidance to advance sequence-based methylation data analysis and methodological development. Availability and implementation: RRBSsim is a simulator for benchmarking analysis of RRBS data and its source code is available at https://github.com/xwBio/RRBSsim or https://github.com/xwBio/Docker-RRBSsim. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Metilação de DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos , Software , Algoritmos , Ilhas de CpG , Epigenômica/métodos , Humanos , Sulfitos
19.
J Am Soc Nephrol ; 29(10): 2518-2528, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30049682

RESUMO

BACKGROUND: In spite of extensive study, the mechanisms for salt sensitivity of BP in humans and rodent models remain poorly understood. Several microRNAs (miRNAs) have been associated with hypertension, but few have been shown to contribute to its development. METHODS: We examined miRNA expression profiles in human kidney biopsy samples and rat models using small RNA deep sequencing. To inhibit an miRNA specifically in the kidney in conscious, freely moving rats, we placed indwelling catheters to allow both renal interstitial administration of a specific anti-miR and measurement of BP. A rat with heterozygous disruption of the gene encoding endothelial nitric oxide synthase (eNOS) was developed. We used bioinformatic analysis to evaluate the relationship between 283 BP-associated human single-nucleotide polymorphisms (SNPs) and 1870 human miRNA precursors, as well as other molecular and cellular methods. RESULTS: Compared with salt-insensitive SS.13BN26 rats, Dahl salt-sensitive (SS) rats showed an upregulation of miR-214-3p, encoded by a gene in the SS.13BN26 congenic region. Kidney-specific inhibition of miR-214-3p significantly attenuated salt-induced hypertension and albuminuria in SS rats. miR-214-3p directly targeted eNOS. The effect of miR-214-3p inhibition on hypertension and albuminuria was abrogated in SS rats with heterozygous loss of eNOS. Human kidney biopsy specimens from patients with hypertension or hypertensive nephrosclerosis showed upregulation of miR-214-3p; the gene encoding miR-214-3p was one of several differentially expressed miRNA genes located in proximity to human BP-associated SNPs. CONCLUSIONS: Renal miR-214-3p plays a functional and potentially genetic role in the development of hypertension, which might be mediated in part by targeting eNOS.


Assuntos
Hipertensão/etiologia , Rim/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Adulto , Animais , Pressão Sanguínea/genética , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , Pessoa de Meia-Idade , Nefroesclerose/genética , Nefroesclerose/metabolismo , Óxido Nítrico Sintase Tipo III/deficiência , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo de Nucleotídeo Único , Ratos , Ratos Endogâmicos Dahl , Ratos Transgênicos , Transcriptoma , Regulação para Cima
20.
Physiol Genomics ; 50(4): 237-243, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29373082

RESUMO

Big data are a major driver in the development of precision medicine. Efficient analysis methods are needed to transform big data into clinically-actionable knowledge. To accomplish this, many researchers are turning toward machine learning (ML), an approach of artificial intelligence (AI) that utilizes modern algorithms to give computers the ability to learn. Much of the effort to advance ML for precision medicine has been focused on the development and implementation of algorithms and the generation of ever larger quantities of genomic sequence data and electronic health records. However, relevance and accuracy of the data are as important as quantity of data in the advancement of ML for precision medicine. For common diseases, physiological genomic readouts in disease-applicable tissues may be an effective surrogate to measure the effect of genetic and environmental factors and their interactions that underlie disease development and progression. Disease-applicable tissue may be difficult to obtain, but there are important exceptions such as kidney needle biopsy specimens. As AI continues to advance, new analytical approaches, including those that go beyond data correlation, need to be developed and ethical issues of AI need to be addressed. Physiological genomic readouts in disease-relevant tissues, combined with advanced AI, can be a powerful approach for precision medicine for common diseases.


Assuntos
Inteligência Artificial , Genômica/métodos , Medicina de Precisão/métodos , Algoritmos , Humanos , Aprendizado de Máquina
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