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1.
Proteins ; 90(4): 959-972, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34850971

RESUMO

Protein-protein interactions (PPIs) are essential in understanding numerous aspects of protein function. Here, we significantly scaled and modified analyses of the recently developed all-vs-all sequencing (AVA-Seq) approach using a gold-standard human protein interaction set (hsPRS-v2) containing 98 proteins. Binary interaction analyses recovered 20 of 47 (43%) binary PPIs from this positive reference set (PRS), comparing favorably with other methods. However, the increase of 20× in the interaction search space for AVA-Seq analysis in this manuscript resulted in numerous changes to the method required for future use in genome-wide interaction studies. We show that standard sequencing analysis methods must be modified to consider the possible recovery of thousands of positives among millions of tested interactions in a single sequencing run. The PRS data were used to optimize data scaling, auto-activator removal, rank interaction features (such as orientation and unique fragment pairs), and statistical cutoffs. Using these modifications to the method, AVA-Seq recovered >500 known and novel PPIs, including interactions between wild-type fragments of tumor protein p53 and minichromosome maintenance complex proteins 2 and 5 (MCM2 and MCM5) that could be of interest in human disease.


Assuntos
Genoma , Proteínas , Humanos , Proteínas/metabolismo
2.
J Transl Med ; 20(1): 244, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35619151

RESUMO

BACKGROUND: Mutated and non-mutated genes interact to drive cancer growth and metastasis. While research has focused on understanding the impact of mutated genes on cancer biology, understanding non-mutated genes that are essential to tumor development could lead to new therapeutic strategies. The recent advent of high-throughput whole genome sequencing being applied to many different samples has made it possible to calculate if genes are significantly non-mutated in a specific cancer patient cohort. METHODS: We carried out random mutagenesis simulations of the human genome approximating the regions sequenced in the publicly available Cancer Growth Atlas Project for ovarian cancer (TCGA-OV). Simulated mutations were compared to the observed mutations in the TCGA-OV cohort and genes with the largest deviations from simulation were identified. Pathway analysis was performed on the non-mutated genes to better understand their biological function. We then compared gene expression, methylation and copy number distributions of non-mutated and mutated genes in cell lines and patient data from the TCGA-OV project. To directly test if non-mutated genes can affect cell proliferation, we carried out proof-of-concept RNAi silencing experiments of a panel of nine selected non-mutated genes in three ovarian cancer cell lines and one primary ovarian epithelial cell line. RESULTS: We identified a set of genes that were mutated less than expected (non-mutated genes) and mutated more than expected (mutated genes). Pathway analysis revealed that non-mutated genes interact in cancer associated pathways. We found that non-mutated genes are expressed significantly more than mutated genes while also having lower methylation and higher copy number states indicating that they could be functionally important. RNAi silencing of the panel of non-mutated genes resulted in a greater significant reduction of cell viability in the cancer cell lines than in the non-cancer cell line. Finally, as a test case, silencing ANKLE2, a significantly non-mutated gene, affected the morphology, reduced migration, and increased the chemotherapeutic response of SKOV3 cells. CONCLUSION: We show that we can identify significantly non-mutated genes in a large ovarian cancer cohort that are well-expressed in patient and cell line data and whose RNAi-induced silencing reduces viability in three ovarian cancer cell lines. Targeting non-mutated genes that are important for tumor growth and metastasis is a promising approach to expand cancer therapeutic options.


Assuntos
Neoplasias Ovarianas , Sequência de Bases , Carcinoma Epitelial do Ovário/genética , Feminino , Genoma , Humanos , Mutação/genética , Neoplasias Ovarianas/genética
3.
J Transl Med ; 20(1): 526, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371196

RESUMO

BACKGROUND: COVID-19 infections could be complicated by acute respiratory distress syndrome (ARDS), increasing mortality risk. We sought to assess the methylome of peripheral blood mononuclear cells in COVID-19 with ARDS. METHODS: We recruited 100 COVID-19 patients with ARDS under mechanical ventilation and 33 non-COVID-19 controls between April and July 2020. COVID-19 patients were followed at four time points for 60 days. DNA methylation and immune cell populations were measured at each time point. A multivariate cox proportional risk regression analysis was conducted to identify predictive signatures according to survival. RESULTS: The comparison of COVID-19 to controls at inclusion revealed the presence of a 14.4% difference in promoter-associated CpGs in genes that control immune-related pathways such as interferon-gamma and interferon-alpha responses. On day 60, 24% of patients died. The inter-comparison of baseline DNA methylation to the last recorded time point in both COVID-19 groups or the intra-comparison between inclusion and the end of follow-up in every group showed that most changes occurred as the disease progressed, mainly in the AIM gene, which is associated with an intensified immune response in those who recovered. The multivariate Cox proportional risk regression analysis showed that higher methylation of the "Apoptotic execution Pathway" genes (ROC1, ZNF789, and H1F0) at inclusion increases mortality risk by over twofold. CONCLUSION: We observed an epigenetic signature of immune-related genes in COVID-19 patients with ARDS. Further, Hypermethylation of the apoptotic execution pathway genes predicts the outcome. TRIAL REGISTRATION: IMRPOVIE study, NCT04473131.


Assuntos
COVID-19 , Síndrome do Desconforto Respiratório , Humanos , COVID-19/complicações , COVID-19/genética , Metilação de DNA/genética , Leucócitos Mononucleares , Respiração Artificial , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/genética , SARS-CoV-2
4.
Cancer Cell Int ; 22(1): 376, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457029

RESUMO

BACKGROUND: Colon cancer is often driven by mutations of the adenomatous polyposis coli (APC) gene, an essential tumor suppressor gene of the Wnt ß-catenin signaling pathway. APC and its cytoplasmic interactions have been well studied. However, various groups have also observed its presence in the nucleus. Identifying novel interactions of APC in the Wnt pathway will provide an opportunity to understand APC's nuclear role better and ultimately identify potential cancer treatment targets. METHODS: We used the all-vs-all sequencing (AVA-Seq) method to interrogate the interactome of protein fragments spanning most of the 60 Wnt ß-catenin pathway proteins. Using protein fragments identified the interacting regions between the proteins with more resolution than a full-length protein approach. Pull-down assays were used to validate a subset of these interactions. RESULTS: 74 known and 703 novel Wnt ß-catenin pathway protein-protein interactions were recovered in this study. There were 8 known and 31 novel APC protein-protein interactions. Novel interactions of APC and nuclear transcription factors TCF7, JUN, FOSL1, and SOX17 were particularly interesting and confirmed in validation assays. CONCLUSION: Based on our findings of novel interactions between APC and transcription factors and previous evidence of APC localizing to the nucleus, we suggest APC may compete and repress CTNNB1. This would occur through APC binding to the transcription factors (JUN, FOSL1, TCF7) to regulate the Wnt signaling pathway including through enhanced marking of CTNNB1 for degradation in the nucleus by APC binding with SOX17. Additional novel Wnt ß-catenin pathway protein-protein interactions from this study could lead researchers to novel drug designs for cancer.

5.
Clin Infect Dis ; 73(7): e1830-e1840, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33315061

RESUMO

BACKGROUND: Risk of reinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unknown. We assessed the risk and incidence rate of documented SARS-CoV-2 reinfection in a cohort of laboratory-confirmed cases in Qatar. METHODS: All SARS-CoV-2 laboratory-confirmed cases with at least 1 polymerase chain reaction-positive swab that was ≥45 days after a first positive swab were individually investigated for evidence of reinfection. Viral genome sequencing of the paired first positive and reinfection viral specimens was conducted to confirm reinfection. RESULTS: Out of 133 266 laboratory-confirmed SARS-CoV-2 cases, 243 persons (0.18%) had at least 1 subsequent positive swab ≥45 days after the first positive swab. Of these, 54 cases (22.2%) had strong or good evidence for reinfection. Median time between the first swab and reinfection swab was 64.5 days (range, 45-129). Twenty-three of the 54 cases (42.6%) were diagnosed at a health facility, suggesting presence of symptoms, while 31 (57.4%) were identified incidentally through random testing campaigns/surveys or contact tracing. Only 1 person was hospitalized at the time of reinfection but was discharged the next day. No deaths were recorded. Viral genome sequencing confirmed 4 reinfections of 12 cases with available genetic evidence. Reinfection risk was estimated at 0.02% (95% confidence interval [CI], .01%-.02%), and reinfection incidence rate was 0.36 (95% CI, .28-.47) per 10 000 person-weeks. CONCLUSIONS: SARS-CoV-2 reinfection can occur but is a rare phenomenon suggestive of protective immunity against reinfection that lasts for at least a few months post primary infection.


Assuntos
COVID-19 , SARS-CoV-2 , Busca de Comunicante , Humanos , Incidência , Reinfecção
6.
PLoS Med ; 18(12): e1003879, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34914711

RESUMO

BACKGROUND: The epidemiology of the SARS-CoV-2 B.1.1.7 (or Alpha) variant is insufficiently understood. This study's objective was to describe the introduction and expansion of this variant in Qatar and to estimate the efficacy of natural infection against reinfection with this variant. METHODS AND FINDINGS: Reinfections with the B.1.1.7 variant and variants of unknown status were investigated in a national cohort of 158,608 individuals with prior PCR-confirmed infections and a national cohort of 42,848 antibody-positive individuals. Infections with B.1.1.7 and variants of unknown status were also investigated in a national comparator cohort of 132,701 antibody-negative individuals. B.1.1.7 was first identified in Qatar on 25 December 2020. Sudden, large B.1.1.7 epidemic expansion was observed starting on 18 January 2021, triggering the onset of epidemic's second wave, 7 months after the first wave. B.1.1.7 was about 60% more infectious than the original (wild-type) circulating variants. Among persons with a prior PCR-confirmed infection, the efficacy of natural infection against reinfection was estimated to be 97.5% (95% CI: 95.7% to 98.6%) for B.1.1.7 and 92.2% (95% CI: 90.6% to 93.5%) for variants of unknown status. Among antibody-positive persons, the efficacy of natural infection against reinfection was estimated to be 97.0% (95% CI: 92.5% to 98.7%) for B.1.1.7 and 94.2% (95% CI: 91.8% to 96.0%) for variants of unknown status. A main limitation of this study is assessment of reinfections based on documented PCR-confirmed reinfections, but other reinfections could have occurred and gone undocumented. CONCLUSIONS: In this study, we observed that introduction of B.1.1.7 into a naïve population can create a major epidemic wave, but natural immunity in those previously infected was strongly associated with limited incidence of reinfection by B.1.1.7 or other variants.


Assuntos
COVID-19/epidemiologia , COVID-19/virologia , Reinfecção/epidemiologia , Reinfecção/virologia , SARS-CoV-2 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Número Básico de Reprodução , Criança , Feminino , Humanos , Imunidade Inata , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Reação em Cadeia da Polimerase , Catar/epidemiologia , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
7.
Hum Mol Genet ; 28(23): 3970-3981, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625567

RESUMO

The effectiveness of next generation sequencing at solving genetic disease has motivated the rapid adoption of this technology into clinical practice around the world. In this study, we use whole exome sequencing (WES) to assess 48 patients with Mendelian disease from 30 serial families as part of the "Qatar Mendelian Disease pilot program" - a coordinated multi-center effort to build capacity and clinical expertise in genetic medicine in Qatar. By enrolling whole families (parents plus available siblings), we demonstrate significantly improved discriminatory power for candidate variant identification over trios for both de novo and recessive inheritance patterns. For the same index cases, we further demonstrate that even in the absence of families, variant prioritization is improved up to 8-fold when a modest set of population-matched controls is used vs large public databases, stressing the poor representation of Middle Eastern alleles in presently available databases. Our in-house pipeline identified candidate disease variants in 27 of 30 families (90%), 23 of which (85%) harbor novel pathogenic variants in known disease genes, pointing to significant allelic heterogeneity and founder mutations underlying Mendelian disease in the Middle East. For 6 of these families, the clinical presentation was only partially explained by the candidate gene, suggesting phenotypic expansion of known syndromes. Our pilot study demonstrates the utility of WES for Middle Eastern populations, the dramatic improvement in variant prioritization conferred by enrolling population-matched controls and/or enrolling additional unaffected siblings at the point-of-care, and 25 novel disease-causing alleles, relevant to newborn and premarital screening panels in regional populations.


Assuntos
Sequenciamento do Exoma/métodos , Heterogeneidade Genética , Predisposição Genética para Doença/genética , Feminino , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Linhagem , Fenótipo , Projetos Piloto , Sistemas Automatizados de Assistência Junto ao Leito , Catar
8.
RNA ; 25(12): 1765-1778, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31519742

RESUMO

Circular RNAs (circRNAs) are abundant in eukaryotic transcriptomes and have been linked to various human disorders. However, understanding genetic control of circular RNA expression is in the early stages. Here we present the first integrated analysis of circRNAs and genome sequence variation from lymphoblastoid cell lines of the 1000 Genomes Project. We identified thousands of circRNAs in the RNA-seq data and show their association with local single-nucleotide polymorphic sites, referred to as circQTLs, which influence the circRNA transcript abundance. Strikingly, we found that circQTLs exist independently of eQTLs with most circQTLs having no effect on mRNA expression. Only a fraction of the polymorphic sites are shared and linked to both circRNA and mRNA expression with mostly similar effects on circular and linear RNA. A shared intronic QTL, rs55928920, of HMSD gene drives the circular and linear expression in opposite directions, potentially modulating circRNA levels at the expense of mRNA. Finally, circQTLs and eQTLs are largely independent and exist in separate linkage disequilibrium (LD) blocks with circQTLs highly enriched for functional genomic elements and regulatory regions. This study reveals a previously uncharacterized role of DNA sequence variation in human circular RNA regulation.


Assuntos
Regulação da Expressão Gênica , Variação Genética , RNA Circular , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , RNA Mensageiro/genética , Análise de Sequência de DNA , Transcriptoma
9.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199764

RESUMO

Pre-mRNA splicing is an essential step in gene expression and is catalyzed by two machineries in eukaryotes: the major (U2 type) and minor (U12 type) spliceosomes. While the majority of introns in humans are U2 type, less than 0.4% are U12 type, also known as minor introns (mi-INTs), and require a specialized spliceosome composed of U11, U12, U4atac, U5, and U6atac snRNPs. The high evolutionary conservation and apparent splicing inefficiency of U12 introns have set them apart from their major counterparts and led to speculations on the purpose for their existence. However, recent studies challenged the simple concept of mi-INTs splicing inefficiency due to low abundance of their spliceosome and confirmed their regulatory role in alternative splicing, significantly impacting the expression of their host genes. Additionally, a growing list of minor spliceosome-associated diseases with tissue-specific pathologies affirmed the importance of minor splicing as a key regulatory pathway, which when deregulated could lead to tissue-specific pathologies due to specific alterations in the expression of some minor-intron-containing genes. Consequently, uncovering how mi-INTs splicing is regulated in a tissue-specific manner would allow for better understanding of disease pathogenesis and pave the way for novel therapies, which we highlight in this review.


Assuntos
Doença/genética , Íntrons/genética , Splicing de RNA/genética , Animais , Evolução Molecular , Humanos , Especificidade de Órgãos/genética , Spliceossomos/metabolismo
10.
J Biol Chem ; 294(30): 11549-11558, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31182485

RESUMO

Two-hybrid systems can be used for investigating protein-protein interactions and may provide important information about gene products with unknown function. Despite their success in mapping protein interactions, two-hybrid systems have remained mostly untouched by improvements in next-generation DNA sequencing. The two-hybrid systems rely on one-versus-all methods in which each bait is sequentially screened against an entire library. Here, we developed a screening method that joins both bait and prey as a convergent fusion into one bacterial plasmid vector that can then be amplified and paired-end sequencing by next-generation sequencing (NGS). Our method enables all-versus-all sequencing (AVA-Seq) and utilizes NGS to remove multiple bottlenecks of the two-hybrid system. AVA-Seq allows for high-resolution protein-protein interaction mapping of a small set of proteins and has the potential for lower-resolution mapping of entire proteomes. Features of the system include ORF selection to improve efficiency, high bacterial transformation efficiency, a convergent fusion vector to allow paired-end sequencing of interactors, and the use of protein fragments rather than full-length proteins to better resolve specific protein contact points. We demonstrate the system's strengths and limitations on a set of proteins known to interact in humans and provide a framework for future large-scale projects.


Assuntos
Mapeamento de Interação de Proteínas/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Reprodutibilidade dos Testes , Técnicas do Sistema de Duplo-Híbrido
11.
Hum Mol Genet ; 27(6): 1106-1121, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29325019

RESUMO

Epigenetic regulation of cellular function provides a mechanism for rapid organismal adaptation to changes in health, lifestyle and environment. Associations of cytosine-guanine di-nucleotide (CpG) methylation with clinical endpoints that overlap with metabolic phenotypes suggest a regulatory role for these CpG sites in the body's response to disease or environmental stress. We previously identified 20 CpG sites in an epigenome-wide association study (EWAS) with metabolomics that were also associated in recent EWASs with diabetes-, obesity-, and smoking-related endpoints. To elucidate the molecular pathways that connect these potentially regulatory CpG sites to the associated disease or lifestyle factors, we conducted a multi-omics association study including 2474 mass-spectrometry-based metabolites in plasma, urine and saliva, 225 NMR-based lipid and metabolite measures in blood, 1124 blood-circulating proteins using aptamer technology, 113 plasma protein N-glycans and 60 IgG-glyans, using 359 samples from the multi-ethnic Qatar Metabolomics Study on Diabetes (QMDiab). We report 138 multi-omics associations at these CpG sites, including diabetes biomarkers at the diabetes-associated TXNIP locus, and smoking-specific metabolites and proteins at multiple smoking-associated loci, including AHRR. Mendelian randomization suggests a causal effect of metabolite levels on methylation of obesity-associated CpG sites, i.e. of glycerophospholipid PC(O-36: 5), glycine and a very low-density lipoprotein (VLDL-A) on the methylation of the obesity-associated CpG loci DHCR24, MYO5C and CPT1A, respectively. Taken together, our study suggests that multi-omics-associated CpG methylation can provide functional read-outs for the underlying regulatory response mechanisms to disease or environmental insults.


Assuntos
Ilhas de CpG , Metilação de DNA , Transtornos do Metabolismo de Glucose/genética , Obesidade/genética , Fumar Tabaco/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Transporte/genética , Biologia Computacional/métodos , Epigênese Genética , Feminino , Estudos de Associação Genética/métodos , Genoma Humano , Estudo de Associação Genômica Ampla/métodos , Humanos , Lipídeos/sangue , Masculino , Metaboloma , Proteínas Repressoras/genética
12.
Reprod Biomed Online ; 41(4): 579-583, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32819839

RESUMO

RESEARCH QUESTION: Long non-coding RNA (lncRNA) do not show protein translation but do have gene regulatory functions in several disease states. Studies have shown that lncRNA differ in overweight women with polycystic ovary syndrome (PCOS), increased insulin resistance and hyperandrogenaemia. The objective of this study was to determine the lncRNA in serum in age- and weight-matched non-obese women with and without PCOS. METHODS: In this prospective pilot cohort study, lncRNA were measured in serum in 13 non-obese women with PCOS and 10 control women undergoing IVF. RESULTS: There was no difference between groups in terms of age, body mass index or insulin resistance. Women with PCOS showed a higher free androgen index (FAI; P = 0.03) and anti-Müllerian hormone (AMH) concentration (P = 0.001). A total of 29 lncRNA (P ≤ 0.05) differed between PCOS groups. lncRNA AC095350.1 correlated with age (r = 0.79, P = 0.04), but no correlation was seen between the significantly different lncRNA and FAI or AMH values. Functional pathway assessment using the Ingenuity Pathway Assessment tool showed no relationships for the lncRNA. CONCLUSION: lncRNA in serum differed between non-obese women with PCOS and the control group, and the pattern of expression differed from that reported in obese women with PCOS from the same ethnic population; however, it but did not correlate with androgen or insulin resistance.


Assuntos
Índice de Massa Corporal , Hiperandrogenismo/metabolismo , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/metabolismo , RNA Longo não Codificante/metabolismo , Adulto , Glicemia , Estudos de Casos e Controles , Feminino , Humanos , Hiperandrogenismo/sangue , Hiperandrogenismo/genética , Insulina/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/genética , Estudos Prospectivos , RNA Longo não Codificante/genética , Testosterona/sangue
13.
BMC Genomics ; 20(1): 498, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208317

RESUMO

BACKGROUND: The date palm is one of the oldest cultivated fruit trees. The tree can withstand high temperatures and low water and the fruit can be stored dry offering nutrition across the year. The first region of cultivation is believed to be near modern day Iraq, however, where and if the date palm was domesticated is still a topic of debate. Recent studies of chloroplast and genomic DNA revealed two major subpopulations of cultivars centered in both the Eastern range of date palm cultivation including Arabian Peninsula, Iraq and parts of South Asia, and the Western range, including North Africa. RESULTS: To better understand the origins of date palm cultivation we sequenced and analyzed over 200 mitochondrial and chloroplast genomes from a geographically diverse set of date palms. Here we show that, based on mitochondrial and chloroplast genome-wide genotyping data, the most common cultivated date palms contain 4 haplotypes that appear associated with geographical region of cultivar origin. CONCLUSIONS: These data suggest at least 3 and possibly 4 original maternal contributions to the current date palm population and doubles the original number. One new haplotype was found mainly in Tunisia, Algeria and Egypt and the second in Iraq, Iran and Oman. We propose that earliest date palm cultivation occurred independently in at least 3 distinct locations. This discovery will further inform understanding of the history and origins of cultivated date palm.


Assuntos
Organelas/genética , Phoeniceae/genética , Sequenciamento Completo do Genoma , Sequência de Bases , Haplótipos/genética , Phoeniceae/classificação
14.
Genome Res ; 26(2): 151-62, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26728717

RESUMO

An open question in the history of human migration is the identity of the earliest Eurasian populations that have left contemporary descendants. The Arabian Peninsula was the initial site of the out-of-Africa migrations that occurred between 125,000 and 60,000 yr ago, leading to the hypothesis that the first Eurasian populations were established on the Peninsula and that contemporary indigenous Arabs are direct descendants of these ancient peoples. To assess this hypothesis, we sequenced the entire genomes of 104 unrelated natives of the Arabian Peninsula at high coverage, including 56 of indigenous Arab ancestry. The indigenous Arab genomes defined a cluster distinct from other ancestral groups, and these genomes showed clear hallmarks of an ancient out-of-Africa bottleneck. Similar to other Middle Eastern populations, the indigenous Arabs had higher levels of Neanderthal admixture compared to Africans but had lower levels than Europeans and Asians. These levels of Neanderthal admixture are consistent with an early divergence of Arab ancestors after the out-of-Africa bottleneck but before the major Neanderthal admixture events in Europe and other regions of Eurasia. When compared to worldwide populations sampled in the 1000 Genomes Project, although the indigenous Arabs had a signal of admixture with Europeans, they clustered in a basal, outgroup position to all 1000 Genomes non-Africans when considering pairwise similarity across the entire genome. These results place indigenous Arabs as the most distant relatives of all other contemporary non-Africans and identify these people as direct descendants of the first Eurasian populations established by the out-of-Africa migrations.


Assuntos
Árabes/genética , População Negra/genética , Migração Humana , Homem de Neandertal/genética , População Branca/genética , Animais , Análise por Conglomerados , DNA Mitocondrial/genética , Frequência do Gene , Humanos , Hibridização Genética , Cadeias de Markov , Modelos Genéticos , Filogenia , Análise de Componente Principal , Catar , Análise de Sequência de DNA
15.
Clin Endocrinol (Oxf) ; 91(6): 793-797, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31482638

RESUMO

Long noncoding RNAs (lncRNAs) are RNA transcripts over 200 nucleotides long that are not translated into protein; however, there is increasing evidence of their regulatory functions. To date, there are few studies measuring lncRNA in control women or women with polycystic ovary syndrome (PCOS). OBJECTIVE: To determine lncRNA differences between PCOS and control women. DESIGN: Cross sectional study. PATIENTS: Twenty four anovulatory women with all three diagnostic features of PCOS compared to 24 control women in the follicular phase of their menstrual cycle from a PCOS biobank. RESULTS: Women with PCOS were age and weight matched compared to the control women but were significantly insulin resistant and hyperandrogenemic (P < .01). Eight lncRNA (P < .05) were detected that differed between PCOS and control women, but only MIRLET7BHG correlated with body mass index (r = .66, P < .05). No lncRNA correlated with antimullerian hormone (AMH) levels, insulin resistance (HOMA-IR) or the free androgen index (FAI). Ingenuity pathway assessment (IPA) did not identify any functional pathways for the lncRNAs. CONCLUSION: LncRNAs differ between anovulatory PCOS and control women in the follicular phase of the menstrual cycle. It is unclear if this is due to inherent differences between PCOS and control women or due to changes in lncRNA that are menstrual cycle dependent. However, their IPA did not identify linked pathways, likely because few functions are as yet assigned to these lncRNAs.


Assuntos
Ciclo Menstrual/fisiologia , Síndrome do Ovário Policístico/genética , RNA Longo não Codificante/genética , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Ciclo Menstrual/genética , Adulto Jovem
16.
BMC Cancer ; 19(1): 565, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31185953

RESUMO

BACKGROUND: Circular RNAs (circRNAs) that form through non-canonical backsplicing events of pre-mRNA transcripts are evolutionarily conserved and abundantly expressed across species. However, the functional relevance of circRNAs remains a topic of debate. METHODS: We identified one of the highly expressed circRNA (circANKRD12) in cancer cell lines and characterized it validated it by Sanger sequencing, Real-Time PCR. siRNA mediated silencing of the circular junction of circANKRD12 was followed by RNA Seq analysis of circANKRD12 silenced cells and control cells to identify the differentially regulated genes. A series of cell biology and molecular biology techniques (MTS assay, Migration analysis, 3D organotypic models, Real-Time PCR, Cell cycle analysis, Western blot analysis, and Seahorse Oxygen Consumption Rate analysis) were performed to elucidate the function, and underlying mechanisms involved in circANKRD12 silenced breast and ovarian cancer cells. RESULTS: In this study, we identified and characterized a circular RNA derived from Exon 2 and Exon 8 of the ANKRD12 gene, termed here as circANKRD12. We show that this circRNA is abundantly expressed in breast and ovarian cancers. The circANKRD12 is RNase R resistant and predominantly localized in the cytoplasm in contrast to its source mRNA. We confirmed the expression of this circRNA across a variety of cancer cell lines and provided evidence for its functional relevance through downstream regulation of several tumor invasion genes. Silencing of circANKRD12 induces a strong phenotypic change by significantly regulating cell cycle, increasing invasion and migration and altering the metabolism in cancer cells. These results reveal the functional significance of circANKRD12 and provide evidence of a regulatory role for this circRNA in cancer progression. CONCLUSIONS: Our study demonstrates the functional relevance of circANKRD12 in various cancer cell types and, based on its expression pattern, has the potential to become a new clinical biomarker.


Assuntos
Inativação Gênica , Invasividade Neoplásica/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Circular/genética , Biomarcadores Tumorais/genética , Mama/citologia , Neoplasias da Mama/patologia , Movimento Celular , Ciclina D1/metabolismo , Éxons/genética , Pontos de Checagem da Fase G1 do Ciclo Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Pulmão/citologia , Neoplasias Pulmonares/patologia , Células MCF-7 , Fenótipo , RNA Interferente Pequeno/genética , Transfecção
17.
PLoS Genet ; 12(1): e1005755, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26735499

RESUMO

Identifying genes where a variant allele is preferentially expressed in tumors could lead to a better understanding of cancer biology and optimization of targeted therapy. However, tumor sample heterogeneity complicates standard approaches for detecting preferential allele expression. We therefore developed a novel approach combining genome and transcriptome sequencing data from the same sample that corrects for sample heterogeneity and identifies significant preferentially expressed alleles. We applied this analysis to epithelial ovarian cancer samples consisting of matched primary ovary and peritoneum and lymph node metastasis. We find that preferentially expressed variant alleles include germline and somatic variants, are shared at a relatively high frequency between patients, and are in gene networks known to be involved in cancer processes. Analysis at a patient level identifies patient-specific preferentially expressed alleles in genes that are targets for known drugs. Analysis at a site level identifies patterns of site specific preferential allele expression with similar pathways being impacted in the primary and metastasis sites. We conclude that genes with preferentially expressed variant alleles can act as cancer drivers and that targeting those genes could lead to new therapeutic strategies.


Assuntos
Redes Reguladoras de Genes , Proteínas de Neoplasias/biossíntese , Neoplasias Ovarianas/genética , Transcriptoma , Alelos , Desequilíbrio Alélico/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células Germinativas , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Proteínas de Neoplasias/genética , Neoplasias Ovarianas/patologia
18.
Int J Mol Sci ; 20(14)2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31336560

RESUMO

Transcriptome profiling of 3D models compared to 2D models in various cancer cell lines shows differential expression of TGF-ß-mediated and cell adhesion pathways. Presence of TGF-ß in these cell lines shows an increased invasion potential which is specific to cell type. In the present study, we identified exogenous addition of TGF-ß can induce Epithelial to Mesenchymal Transition (EMT) in a few cancer cell lines. RNA sequencing and real time PCR were carried out in different ovarian cancer cell lines to identify molecular profiling and metabolic profiling. Since EMT induction by TGF-ß is cell-type specific, we decided to select two promising ovarian cancer cell lines as model systems to study EMT. TGF-ß modulation in EMT and cancer invasion were successfully depicted in both 2D and 3D models of SKOV3 and CAOV3 cell lines. Functional evaluation in 3D and 2D models demonstrates that the addition of the exogenous TGF-ß can induce EMT and invasion in cancer cells by turning them into aggressive phenotypes. TGF-ß receptor kinase I inhibitor (LY364947) can revert the TGF-ß effect in these cells. In a nutshell, TGF-ß can induce EMT and migration, increase aggressiveness, increase cell survival, alter cell characteristics, remodel the Extracellular Matrix (ECM) and increase cell metabolism favorable for tumor invasion and metastasis. We concluded that transcriptomic and phenotypic effect of TGF-ß and its inhibitor is cell-type specific and not cancer specific.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Inibidores de Proteínas Quinases/farmacologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Matriz Extracelular , Feminino , Humanos , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
19.
Genet Med ; 20(11): 1365-1373, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29790874

RESUMO

PURPOSE: Nonobstructive azoospermia (NOA) affects 1% of the male population; however, despite state-of-the-art clinical assessment, for most patients the cause is unknown. We capitalized on an analysis of multiplex families in the Middle East to identify highly penetrant genetic causes. METHODS: We used whole-exome sequencing (WES) in 8 consanguineous families and combined newly discovered genes with previously reported ones to create a NOA gene panel, which was used to identify additional variants in 75 unrelated idiopathic NOA subjects and 74 fertile controls. RESULTS: In five of eight families, we identified rare deleterious recessive variants in CCDC155, NANOS2, SPO11, TEX14, and WNK3 segregating with disease. These genes, which are novel to human NOA, have remarkable testis-specific expression, and murine functional evidence supports roles for them in spermatogenesis. Among 75 unrelated NOA subjects, we identified 4 (~5.3%) with additional recessive variants in these newly discovered genes and 6 with deleterious variants in previously reported NOA genes, yielding an overall genetic etiology for 13.3% subjects versus 0 fertile controls (p = 0.001). CONCLUSION: NOA affects millions of men, many of whom remain idiopathic despite extensive laboratory evaluation. The genetic etiology for a substantial fraction of these patients (>50% familial and >10% sporadic) may be discovered by WES at the point of care.


Assuntos
Azoospermia/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Infertilidade Masculina/genética , Adulto , Azoospermia/epidemiologia , Azoospermia/fisiopatologia , Proteínas de Ciclo Celular/genética , Consanguinidade , Endodesoxirribonucleases/genética , Humanos , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/fisiopatologia , Masculino , Oriente Médio , Mutação , Proteínas Nucleares/genética , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas de Ligação a RNA/genética , Espermatogênese/genética , Fatores de Transcrição/genética , Sequenciamento do Exoma
20.
Ann Neurol ; 81(1): 68-78, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27863452

RESUMO

OBJECTIVE: Exome sequences account for only 2% of the genome and may overlook mutations causing disease. To obtain a more complete view, whole genome sequencing (WGS) was analyzed in a large consanguineous family in which members displayed autosomal recessively inherited cerebellar ataxia manifesting before 2 years of age. METHODS: WGS from blood-derived genomic DNA was used for homozygosity mapping and a rare variant search. RNA from isolated blood leukocytes was used for quantitative polymerase chain reaction (PCR), RNA sequencing, and comparison of the transcriptomes of affected and unaffected family members. RESULTS: WGS revealed a point mutation in noncoding RNA RNU12 that was associated with early onset cerebellar ataxia. The U12-dependent minor spliceosome edits 879 known transcripts. Reverse transcriptase PCR demonstrated minor intron retention in all of 9 randomly selected RNAs from this group, and RNAseq showed splicing disruption specific to all U12-type introns detected in blood monocytes from affected individuals. Moreover, 144 minor intron-containing RNAs were differentially expressed, including transcripts for 3 genes previously associated with cerebellar neurodegeneration. INTERPRETATION: Interference with particular spliceosome components, including small nuclear RNAs, cause reproducible uniquely distributed phenotypic and transcript-specific effects, making this an important category of disease-associated mutation. Our approach to differential expression analysis of minor intron-containing genes is applicable to other diseases involving altered transcriptome processing. ANN NEUROL 2017;81:68-78.


Assuntos
Predisposição Genética para Doença/genética , RNA Nuclear Pequeno/genética , RNA não Traduzido/genética , Degenerações Espinocerebelares/genética , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Mutação Puntual , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de RNA , Adulto Jovem
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