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1.
Cell Mol Biol Lett ; 29(1): 66, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724931

RESUMO

The development of compact CRISPR systems has facilitated delivery but has concurrently reduced gene editing efficiency, thereby limiting the further utilization of CRISPR systems. Enhancing the efficiency of CRISPR systems poses a challenging task and holds significant implications for the advancement of biotechnology. In our work, we report a synthetic dual-antibody system that can stably exist in the intracellular environment, specifically inhibiting the functions of NF-κB and ß-catenin. This not only elevates the transgenic expression of the CRISPR system by suppressing the innate immune response within cells to enhance the gene editing efficiency but also demonstrates a notable tumor inhibitory effect. Based on the specific output expression regulation of CRISPR-CasΦ, we constructed a CRISPR-based gene expression platform, which includes sensor modules for detecting intracellular ß-catenin and NF-κB, as well as an SDA module to enhance overall efficiency. In vitro experiments revealed that the CRISPR-based gene expression platform exhibited superior CDK5 expression inhibition efficiency and specific cytotoxicity towards tumor cells. In vitro experiments, we found that CRISPR-based gene expression platforms can selectively kill bladder cancer cells through T cell-mediated cytotoxicity. Our design holds significant assistant potential of transgene therapy and may offer the capability to treat other diseases requiring transgene therapy.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/terapia , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Edição de Genes/métodos , beta Catenina/metabolismo , beta Catenina/genética , NF-kappa B/metabolismo , NF-kappa B/genética , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética
2.
Mol Biol Rep ; 51(1): 652, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734792

RESUMO

OBJECTIVE: To compare the mRNA expression of placental iron transporters (TfR-1 and FPN), markers of placental vascularization (VEGF and sFLT1) and marker of structural integrity (LMN-A) in term women with and without iron deficiency anemia. MATERIALS AND METHODS: A total of 30 pregnant women were enrolled; 15 cases of iron deficiency anemia (Hb 7-10.9 gm/dL) and 15 gestational age matched healthy controls (Hb ≥ 11 gm/dL). Peripheral venous blood was collected for assessment of hemoglobin levels and serum iron profile. Placental tissue was used for assessing the mRNA expression of TfR-1, FPN, VEGF, sFLT-1 and LMN-A via real time PCR. RESULTS: Placental expression of TfR-1, VEGF and LMN-A was increased in pregnant women with anemia compared to healthy pregnant controls. Placental expression of sFLT-1 was decreased in pregnant women with anemia compared to healthy pregnant controls. There was no change in the placental expression of FPN. CONCLUSION: The increased expression of TfR-1, VEGF and LMN-A in cases of iron deficiency anemia are most likely to be compensatory in nature to help maintain adequate fetal iron delivery. WHAT DOES THIS STUDY ADDS TO THE CLINICAL WORK: Compensatory changes in the placenta aimed at buffering transport of iron to the fetus are seen in pregnant women with anemia compared to healthy pregnant controls.


Assuntos
Anemia Ferropriva , Biomarcadores , Proteínas de Transporte de Cátions , Ferro , Placenta , Receptores da Transferrina , Fator A de Crescimento do Endotélio Vascular , Humanos , Feminino , Gravidez , Placenta/metabolismo , Adulto , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Anemia Ferropriva/genética , Anemia Ferropriva/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Ferro/metabolismo , Biomarcadores/metabolismo , Biomarcadores/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Estudos de Casos e Controles , Antígenos CD/metabolismo , Antígenos CD/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Expressão Gênica/genética
3.
Methods Mol Biol ; 2787: 245-253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656494

RESUMO

To properly assess promoter activity, which is critical for understanding biosynthetic pathways in different plant species, we use agroinfiltration-based transient gene expression assay. We compare the activity of several known promoters in Nicotiana benthamiana with their activity in Cannabis sativa (both hemp and medicinal cannabis), which has attracted much attention in recent years for its industrial, medicinal, and recreational properties. Here we describe an optimized protocol for transient expression in Cannabis combined with a ratiometric GUS reporter system that allows more accurate evaluation of promoter activity and reduces the effects of variable infiltration efficiency.


Assuntos
Cannabis , Regulação da Expressão Gênica de Plantas , Nicotiana , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Cannabis/genética , Cannabis/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Plantas Geneticamente Modificadas/genética , Genes Reporter , Expressão Gênica/genética , Glucuronidase/genética , Glucuronidase/metabolismo
4.
Mol Biol Rep ; 51(1): 524, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630344

RESUMO

BACKGROUND: Pterygium, characterized by the abnormal proliferation of epithelial cells, matrix remodeling, vascularization, and lesion migration, is a prevalent ocular surface disease involving the growth of fibrovascular tissue on the cornea. Despite the unclear underlying causes of pterygium, numerous investigations have indicated the involvement of cell death pathways in the regulation of cell cycle dynamics. Consequently, the objective of this study was to assess the expression levels of necroptosis markers in individuals diagnosed with pterygium, aiming to shed light on the potential role of necroptosis in the pathogenesis of this condition. METHODS: This study aimed to investigate the expression patterns of receptor-interacting serine/threonine kinase 3 (RIPK3) and receptor-interacting serine/threonine kinase 1 (RIPK1) genes in pterygium tissues. 41 patients undergoing pterygium excision surgery were recruited. Resected pterygium samples and normal conjunctival tissues were collected, and RIPK3 and RIPK1 mRNA levels were measured using quantitative real-time PCR. RESULTS: Our findings reveal that the expression of RIPK3 is significantly increased in samples obtained from individuals with pterygium. However, no significant alterations were observed in the expression of RIPK1 in these samples. Results showed significantly higher RIPK3 expression in pterygium tissues compared to controls. Moreover, increased RIPK3 levels correlated negatively with pterygium recurrence rates. CONCLUSIONS: These findings suggest RIPK3 may play a protective role against pterygium recurrence through necroptosis.


Assuntos
Pterígio , Humanos , Túnica Conjuntiva/anormalidades , Expressão Gênica/genética , Pterígio/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Serina
5.
Mol Biol Rep ; 51(1): 594, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38683374

RESUMO

BACKGROUND: Metacaspases comprise a family of cysteine proteases implicated in both cell death and cell differentiation of protists that has been considered a potential drug target for protozoan parasites. However, the biology of metacaspases in Plasmodium vivax - the second most prevalent and most widespread human malaria parasite worldwide, whose occurrence of chemoresistance has been reported in many endemic countries, remains largely unexplored. Therefore, the present study aimed to address, for the first time, the expression pattern of metacaspases in P. vivax parasites. METHODS AND RESULTS: P. vivax blood-stage parasites were obtained from malaria patients in the Brazilian Amazon and the expression of the three putative P. vivax metacaspases (PvMCA1-3) was detected in all isolates by quantitative PCR assay. Of note, the expression levels of each PvMCA varied noticeably across isolates, which presented different frequencies of parasite forms, supporting that PvMCAs may be expressed in a stage-specific manner as previously shown in P. falciparum. CONCLUSION: The detection of metacaspases in P. vivax blood-stage parasites reported herein, allows the inclusion of these proteases as a potential candidate drug target for vivax malaria, while further investigations are still required to evaluate the activity, role and essentiality of metacaspases in P. vivax biology.


Assuntos
Malária Vivax , Plasmodium vivax , Proteínas de Protozoários , Plasmodium vivax/genética , Plasmodium vivax/isolamento & purificação , Brasil , Humanos , Malária Vivax/parasitologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Caspases/genética , Caspases/metabolismo , Expressão Gênica/genética
6.
Mol Metab ; 83: 101923, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521183

RESUMO

OBJECTIVES: We have previously shown that lactate is an essential metabolite for macrophage polarisation during ischemia-induced muscle regeneration. Recent in vitro work has implicated histone lactylation, a direct derivative of lactate, in macrophage polarisation. Here, we explore the in vivo relevance of histone lactylation for macrophage polarisation after muscle injury. METHODS: To evaluate macrophage dynamics during muscle regeneration, we subjected mice to ischemia-induced muscle damage by ligating the femoral artery. Muscle samples were harvested at 1, 2, 4, and 7 days post injury (dpi). CD45+CD11b+F4/80+CD64+ macrophages were isolated and processed for RNA sequencing, Western Blotting, and CUT&Tag-sequencing to investigate gene expression, histone lactylation levels, and histone lactylation genomic localisation and enrichment, respectively. RESULTS: We show that, over time, macrophages in the injured muscle undergo extensive gene expression changes, which are similar in nature and in timing to those seen after other types of muscle-injuries. We find that the macrophage histone lactylome is modified between 2 and 4 dpi, which is a crucial window for macrophage polarisation. Absolute histone lactylation levels increase, and, although subtly, the genomic enrichment of H3K18la changes. Overall, we find that histone lactylation is important at both promoter and enhancer elements. Lastly, H3K18la genomic profile changes from 2 to 4 dpi were predictive for gene expression changes later in time, rather than being a reflection of prior gene expression changes. CONCLUSIONS: Our results suggest that histone lactylation dynamics are functionally important for the function of macrophages during muscle regeneration.


Assuntos
Histonas , Isquemia , Macrófagos , Camundongos Endogâmicos C57BL , Músculo Esquelético , Regeneração , Animais , Macrófagos/metabolismo , Camundongos , Histonas/metabolismo , Músculo Esquelético/metabolismo , Isquemia/metabolismo , Masculino , Expressão Gênica/genética
7.
J Biol Chem ; 300(3): 105691, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280429

RESUMO

Liver fibrosis commences with liver injury stimulating transforming growth factor beta (TGFß) activation of hepatic stellate cells (HSCs), causing scarring and irreversible damage. TGFß induces expression of the transcription factor Forkhead box S1 (FOXS1) in hepatocytes and may have a role in the pathogenesis of hepatocellular carcinoma (HCC). To date, no studies have determined how it affects HSCs. We analyzed human livers with cirrhosis, HCC, and a murine fibrosis model and found that FOXS1 expression is significantly higher in fibrotic livers but not in HCC. Next, we treated human LX2 HSC cells with TGFß to activate fibrotic pathways, and FOXS1 mRNA was significantly increased. To study TGFß-FOXS1 signaling, we developed human LX2 FOXS1 CRISPR KO and scrambled control HSCs. To determine differentially expressed gene transcripts controlled by TGFß-FOXS1, we performed RNA-seq in the FOXS1 KO and control cells and over 400 gene responses were attenuated in the FOXS1 KO HSCs with TGFß-activation. To validate the RNA-seq findings, we used our state-of-the-art PamGene PamStation kinase activity technology that measures hundreds of signaling pathways nonselectively in real time. Using our RNA-seq data, kinase activity data, and descriptive measurements, we found that FOXS1 controls pathways mediating TGFß responsiveness, protein translation, and proliferation. Our study is the first to identify that FOXS1 may serve as a biomarker for liver fibrosis and HSC activation, which may help with early detection of hepatic fibrosis or treatment options for end-stage liver disease.


Assuntos
Fatores de Transcrição Forkhead , Expressão Gênica , Células Estreladas do Fígado , Cirrose Hepática , Fator de Crescimento Transformador beta , Animais , Humanos , Camundongos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/diagnóstico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Biomarcadores/metabolismo , Técnicas de Inativação de Genes , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Transdução de Sinais/genética
8.
Nat Aging ; 4(2): 177-184, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38228925

RESUMO

A decline in hematopoietic stem cell (HSC) function is believed to underlie hematological shortcomings with age; however, a comprehensive molecular understanding of these changes is currently lacking. Here we provide evidence that a transcriptional signature reported in several previous studies on HSC aging is linked to stress-induced changes in gene expression rather than aging. Our findings have strong implications for the design and interpretation of HSC aging studies.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Expressão Gênica/genética
9.
Brain Behav Immun ; 116: 229-236, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38070623

RESUMO

Up to 40 % of individuals who sustain traumatic injuries are at risk for posttraumatic stress disorder (PTSD) and the conditional risk for developing PTSD is even higher for Black individuals. Exposure to racial discrimination, including at both interpersonal and structural levels, helps explain this health inequity. Yet, the relationship between racial discrimination and biological processes in the context of traumatic injury has yet to be fully explored. The current study examined whether racial discrimination is associated with a cumulative measure of biological stress, the gene expression profile conserved transcriptional response to adversity (CTRA), in Black trauma survivors. Two-weeks (T1) and six-months (T2) post-injury, Black participants (N = 94) provided a blood specimen and completed assessments of lifetime racial discrimination and PTSD symptoms. Mixed effect linear models evaluated the relationship between change in CTRA gene expression and racial discrimination while adjusting for age, gender, body mass index (BMI), smoking history, heavy alcohol use history, and trauma-related variables (mechanism of injury, lifetime trauma). Results revealed that for individuals exposed to higher levels of lifetime racial discrimination, CTRA significantly increased between T1 and T2. Conversely, CTRA did not increase significantly over time in individuals exposed to lower levels of lifetime racial discrimination. Thus, racial discrimination appeared to lead to a more sensitized biological profile which was further amplified by the effects of a recent traumatic injury. These findings replicate and extend previous research elucidating the processes by which racial discrimination targets biological systems.


Assuntos
Racismo , Transtornos de Estresse Pós-Traumáticos , Humanos , Centros de Traumatologia , População Negra/genética , Transtornos de Estresse Pós-Traumáticos/genética , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Expressão Gênica/genética
10.
Bull Exp Biol Med ; 174(4): 538-543, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36899207

RESUMO

The differentiation potential of individual clones of fibroblast CFU (CFU-F) was studied and the relative expression level of genes was analyzed in the culture of CFU-F from the bone marrow in patients with non-severe and severe forms of aplastic anemia at the onset of the disease. The differentiation potential of CFU-F clones was determined by the relative expression of marker genes using quantitative PCR. In aplastic anemia, the ratio of CFU-F clones with different differentiation potential changes, but the molecular mechanisms of this phenomenon are different in non-severe and severe aplastic anemia. In the culture of CFU-F in non-severe and severe aplastic anemia, the relative expression level of genes associated with the maintenance of the hematopoietic stem cell in the bone marrow niche changes, but the decrease in the expression of immunoregulatory genes occurs in severe form only, which may reflect differences in the pathogenesis of non-severe and severe aplastic anemia.


Assuntos
Anemia Aplástica , Humanos , Anemia Aplástica/genética , Anemia Aplástica/patologia , Medula Óssea/patologia , Células Cultivadas , Células-Tronco Hematopoéticas/patologia , Diferenciação Celular/genética , Gravidade do Paciente , Fibroblastos/patologia , Expressão Gênica/genética , Ensaio de Unidades Formadoras de Colônias
11.
Sleep Breath ; 27(5): 2031-2039, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36917442

RESUMO

PURPOSE: Obstructive sleep apnea (OSA) is characterised by increased systemic inflammation, and is often accompanied with type 2 diabetes mellitus (T2DM) and cardiovascular disease. The aim of this investigation was to evaluate gene expression of resistin, its receptor CAP1 and CD36 as the indicators of the inflammatory changes in PBMCs in relation to the severity of OSA, and the presence of type 2 diabetes mellitus (T2DM) in OSA. METHODS: Severity of OSA was defined by the apnea/hypopnea index (AHI): AHI < 30: mild to moderate OSA (MM-OSA), AHI ≥ 30: severe OSA (S-OSA). Presence of T2DM was captured: OSA with T2DM (OSA + T2DM), OSA without T2DM (OSA-T2DM). PBMC resistin, CAP1, and CD36 mRNA were determined by real-time PCR. RESULTS: Resistin mRNA was significantly upregulated in S-OSA (N = 54) compared to the MM-OSA (N = 52, P = 0.043); CAP1 and CD36 mRNA levels did not differ between the groups (P = 0.302; P = 0.166, respectively). Resistin mRNA was significantly upregulated in OSA + T2DM (N = 29) compared to the OSA-T2DM (N = 77, P = 0.029); CAP1 and CD36 mRNA levels did not differ between the groups (P = 0.662; P = 0.108, respectively). AHI and T2DM were independent predictors of resistin mRNA above the 75th percentile (OR = 3.717 [1.152-11.991]; OR = 3.261 [1.000-10.630], P = 0.042 respectively). CONCLUSION: Resistin gene upregulation in S-OSA indicates its possible contribution to increased inflammation in S-OSA and makes it a possible marker of the disease severity. Resistin gene upregulation in OSA + T2DM suggests that a joint effect of these two comorbidities may have a major contribution to increased inflammation and complications that arise from this state.


Assuntos
Diabetes Mellitus Tipo 2 , Apneia Obstrutiva do Sono , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Leucócitos Mononucleares , Regulação para Cima/genética , Resistina/genética , Inflamação/complicações , Apneia Obstrutiva do Sono/complicações , RNA Mensageiro , Expressão Gênica/genética
12.
J Biol Chem ; 299(2): 102878, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623733

RESUMO

Deletion of O-GlcNAc transferase (Ogt) in pancreatic epithelial progenitor cells results in pancreatic hypoplasia at birth, partly due to increased apoptosis during embryonic development. Constitutive loss of Ogt in ß-cells results in increased ER stress and apoptosis, and in the Ogt-deficient pancreas, transcriptomic data previously revealed both tumor suppressor protein p53 and pancreatic duodenal homeobox 1 (Pdx1), key cell survival proteins in the developing pancreas, as upstream regulators of differentially expressed genes. However, the specific roles of these genes in pancreatic hypoplasia are unclear. In this study, we explored the independent roles of p53, ER stress protein CHOP, and Pdx1 in pancreas development and their use in the functional rescue of pancreatic hypoplasia in the context of Ogt loss. Using in vivo genetic manipulation and morphometric analysis, we show that Ogt plays a key regulatory role in pancreas development. Heterozygous, but not homozygous, loss of pancreatic p53 afforded a partial rescue of ß-cell, α-cell, and exocrine cell masses, while whole body loss of CHOP afforded a partial rescue in pancreas weight and a full rescue in exocrine cell mass. However, neither was sufficient to fully mitigate pancreatic hypoplasia at birth in the Ogt-deficient pancreas. Furthermore, overexpression of Pdx1 in the pancreatic epithelium resulted in partial rescues in pancreas weight and ß-cell mass in the Ogt loss background. These findings highlight the requirement of Ogt in pancreas development by targeting multiple proteins such as transcription factor Pdx1 and p53 in the developing pancreas.


Assuntos
Expressão Gênica , Células Secretoras de Glucagon , Pancreatopatias , Proteína Supressora de Tumor p53 , Animais , Camundongos , Células Secretoras de Glucagon/metabolismo , Pâncreas Exócrino/metabolismo , Proteína Supressora de Tumor p53/genética , Expressão Gênica/genética , Pancreatopatias/genética , Pancreatopatias/fisiopatologia
13.
Blood Adv ; 7(6): 893-899, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36240289

RESUMO

We investigated the clinicopathologic features of 5 follicular lymphomas (FLs) that transformed (tFL) morphologically to diffuse large B-cell lymphomas (DLBCLs) and had a primary mediastinal large B-cell lymphoma (PMBL)-like gene expression profile (tFL-PMBLsig-pos). None of the tFL-PMBLsig-pos cases arose in the mediastinum, all cases tested had a germinal center B-cell phenotype, 20% were CD30+, 60% CD23+, 80% MAL+, 20% CD200+, and 0% CD273/PDL2+. Whole-exome sequencing detected alterations in genes associated with both FL/DLBCL (CREBBP, KMT2C, KMT2D, ARID1A, HIST1 members, and TNFRSF14) and PMBL (JAK-STAT pathway genes, B2M, and CD58). Copy number (CN) analysis detected gains/amplification of REL and STAT6 in 60%, gains of SOCS1 in 40%, and gains of chromosome 16, including IL4R, in 40% of the cases. CN gains/amplification of BCL6 and MYC and loss of TNFRSF14 and TNFAIP3 were identified in 20% of the cases. Three of 5 cases lacked a BCL2 rearrangement. Despite having some features that are less common in DLBCL (MAL and CD23 expression and JAK-STAT activation), these tFL-PMBLsig-pos cases lack the most characteristic CN alteration seen in PMBL (9p24.1 gain/amplification). This cohort expands the biologic heterogeneity of tFL, illustrating a subset with gene expression and some genetic features reminiscent of PMBL, with potential treatment implications that include the use of novel targeted therapies.


Assuntos
Linfoma Folicular , Linfoma Difuso de Grandes Células B , Transcriptoma , Humanos , Janus Quinases , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Transdução de Sinais , Fatores de Transcrição STAT , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Linfoma Folicular/patologia , Expressão Gênica/genética , Expressão Gênica/fisiologia
14.
PLoS Genet ; 18(12): e1010535, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36508455

RESUMO

Noise in expression of individual genes gives rise to variations in activity of cellular pathways and generates heterogeneity in cellular phenotypes. Phenotypic heterogeneity has important implications for antibiotic persistence, mutation penetrance, cancer growth and therapy resistance. Specific molecular features such as the presence of the TATA box sequence and the promoter nucleosome occupancy have been associated with noise. However, the relative importance of these features in noise regulation is unclear and how well these features can predict noise has not yet been assessed. Here through an integrated statistical model of gene expression noise in yeast we found that the number of regulating transcription factors (TFs) of a gene was a key predictor of noise, whereas presence of the TATA box and the promoter nucleosome occupancy had poor predictive power. With an increase in the number of regulatory TFs, there was a rise in the number of cooperatively binding TFs. In addition, an increased number of regulatory TFs meant more overlaps in TF binding sites, resulting in competition between TFs for binding to the same region of the promoter. Through modeling of TF binding to promoter and application of stochastic simulations, we demonstrated that competition and cooperation among TFs could increase noise. Thus, our work uncovers a process of noise regulation that arises out of the dynamics of gene regulation and is not dependent on any specific transcription factor or specific promoter sequence.


Assuntos
Expressão Gênica , Fatores de Transcrição , Sítios de Ligação/genética , Expressão Gênica/genética , Expressão Gênica/fisiologia , Nucleossomos/metabolismo , Ligação Proteica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
J Mol Evol ; 90(5): 389-399, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36029325

RESUMO

High-elevation adaptation provides an excellent system for examining adaptive evolution, and adaptive variations may manifest at gene expression or any other phenotypic levels. We examined gene expression profiles of Asiatic toads (Bufo gargarizans) along an elevational gradient from both wild and common-garden acclimated populations. Asiatic toads originated from high altitudes have distinctive gene expression patterns. We identified 18 fixed differentially expressed genes (DEGs), which are different in both wild and acclimated samples, and 1217 plastic DEGs, which are different among wild samples. The expression levels of most genes were linearly correlated with altitude gradient and down-regulated in high-altitude populations. Expression variations of several genes associated with metabolic process are fixed, and we also identified a co-expression module that is significantly different between acclimated populations and has functions related to DNA repair. The differential expression of the vast majority genes, however, are due to phenotypic plasticity, revealing the highly plastic nature of gene expression variations. Expression modification of some specific genes related to metabolism and response to UV radiation play crucial role in adaptation to high altitude for Asiatic toads. Common-garden experiments are essential for evaluating adaptive evolution of natural populations.


Assuntos
Bufonidae , Raios Ultravioleta , Altitude , Animais , Bufonidae/genética , Expressão Gênica/genética , Plásticos
16.
Arq. ciências saúde UNIPAR ; 26(2): 159-174, maio-ago. 2022.
Artigo em Português | LILACS | ID: biblio-1372969

RESUMO

A obesidade é definida pelo excesso de gordura corporal acumulada no tecido adiposo quando o indivíduo atinge valores de IMC igual ou superior a 30 Kg/m2. Constitui um dos principais fatores de risco para várias doenças não transmissíveis (DNTs) como por exemplo, diabetes mellitus tipo 2 (DM2), doenças cardiovasculares, hipertensão arterial, acidente vascular cerebral e até mesmo o câncer. Embora a obesidade esteja diretamente relacionada com o consumo calórico excessivo em relação ao gasto energético diário, sua etiologia pode estar associada aos baixos níveis de atividade física, às alterações neuroendócrinas e aos fatores genéticos. Considerando o componente genético, esta pode ser classificada como sindrômicas e estar associada às alterações cromossômicas estruturais ou numéricas, ou como não sindrômica, quando relacionada, principalmente, com os polimorfismos de nucleotídeos simples (SNPs) em alelos que atuam como herança monogênica, ou ainda com a interação vários genes (poligênica multifatorial). Apesar de existirem muitas etiologias diferentes, normalmente a obesidade é tratada a partir da mesma abordagem, desconsiderando a fisiologia que a desencadeou. Dessa forma, o objetivo do presente trabalho foi abordar a obesidade genética não sindrômica por meio a) da descrição breve de perspectiva histórica sobre seu entendimento; b) da exposição dos principais mecanismos moleculares envolvidos com o controle de peso; c) da compilação dos principais genes e SNPs relacionados; d) da definição dos principais genes; e e) da abordagem das principais perspectivas de intervenção.


Obesity is defined as excess body fat accumulated in the adipose tissue when the individual reaches BMI values equal to or greater than 30 kg/m2. It is one of the main risk factors for several non-communicable diseases (NCDs), such as Type 2 Diabetes mellitus (T2D), cardiovascular diseases, high blood pressure, stroke and even cancer. Although obesity is directly related to excessive calorie intake in relation to daily energy expenditure, its etiology may be associated with low levels of physical activity, neuroendocrine changes, and genetic factors. Considering the genetic component, it can be classified as syndromic and be associated with chromosomal or numerical changes, or as non-syndromic and being related mainly to single nucleotide polymorphisms (SNPs) in alleles that act as monogenic inheritance, or with an interaction of several genes (multifactorial polygenic). Although there are many different etiologies, obesity is usually treated using the same approach, disregarding the physiology that triggered it. Thus, the aim of this study was to address non-syndromic genetic obesity through a) a brief description of a historical perspective on its understanding; b) the exposure of the main molecular mechanisms involved in weight control, c) the compilation of the key genes and related SNPs, d) the definition of the key genes and e) the approach of the main intervention representations.


Assuntos
Humanos , Masculino , Feminino , Peso Corporal/genética , Epigenômica , Genes/genética , Obesidade/genética , Índice de Massa Corporal , Expressão Gênica/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 4 de Melanocortina/genética , Melanocortinas/genética , Receptores para Leptina/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Hipotálamo/fisiopatologia , Obesidade/fisiopatologia
17.
Int J Cancer ; 151(5): 770-782, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35583991

RESUMO

Acute myeloid leukemia (AML) results from aberrant hematopoietic processes and these changes are frequently initiated by chromosomal translocations. One particular subtype, AML with translocation t(7;12)(q36;p13), is found in children diagnosed before 2 years of age. The mechanisms for leukemogenesis induced by t(7;12) is not understood, in part because of the lack of efficient methods to reconstruct the leukemia-associated genetic aberration with correct genomic architecture and regulatory elements. We therefore created induced pluripotent stem cell (iPSC) lines that carry the translocation t(7;12) using CRISPR/Cas9. These t(7;12) iPSC showed propensity to differentiate into all three germ layers, confirming retained stem cell properties. The potential for differentiation into hematopoietic stem and progenitor cells (HSPC) was shown by expression of CD34, CD43 and CD45. Compared with the parental iPSC line, a significant decrease in cells expressing CD235a and CD41a was seen in the t(7;12) iPSC-derived HSPC (iHSPC), suggesting a block in differentiation. Moreover, colony formation assay showed an accumulation of cells at the erythroid and myeloid progenitor stages. Gene expression analysis revealed significant down-regulation of genes associated with megakaryocyte differentiation and up-regulation of genes associated with myeloid pathways but also genes typically seen in AML cases with t(7;12). Thus, this iPSC t(7;12) leukemia model of the t(7;12) AML subtype constitutes a valuable tool for further studies of the mechanisms for leukemia development and to find new treatment options.


Assuntos
Diferenciação Celular , Proteínas de Homeodomínio , Células-Tronco Pluripotentes Induzidas , Leucemia Mieloide Aguda , Células Progenitoras de Megacariócitos e Eritrócitos , Fatores de Transcrição , Diferenciação Celular/genética , Criança , Expressão Gênica/genética , Expressão Gênica/fisiologia , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/fisiologia , Proteínas de Homeodomínio/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucemia Mieloide Aguda/genética , Células Progenitoras de Megacariócitos e Eritrócitos/fisiologia , Megacariócitos/fisiologia , Fatores de Transcrição/genética , Translocação Genética
18.
BMC Cancer ; 22(1): 242, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248011

RESUMO

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)-positive tumors are defined by protein overexpression (3+) or gene amplification using immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH), respectively. HER2-positive tumors have historically included both IHC(3+) and IHC(2+, equivocal)/FISH(+) tumors and received the same treatment. Differences in biology between these two tumor types, however, are poorly understood. Considering anti-HER2 drugs bind directly to HER2 protein on the cell surface, we hypothesized anti-HER2 therapies would be less effective in IHC(2+)/FISH(+) tumors than in IHC(3+) tumors, leading to differences in patient outcomes. METHODS: A total of 447 patients with HER2-positive invasive carcinoma who underwent curative surgery were retrospectively investigated. HER2 status was assessed in surgical specimens, except in patients who received neo-adjuvant chemotherapy, where biopsy specimens were employed. RESULTS: Age, tumor size, lymph node status and ER status were independent factors relating to disease-free-survival, but no difference was observed between IHC(3+) and IHC(2+)/FISH(+) tumors. Kaplan-Meier analysis found patient outcomes did not differ, even after stratifying into those that did (n = 314), or did not (n = 129), receive chemotherapy with anti-HER2 drugs. In 134 patients who received NAC, pathological complete response rates in IHC(3+) and IHC(2+)/FISH(+) tumors were 45% and 21%, respectively. Survival after developing metastasis was significantly shorter in the IHC(2+)/FISH(+) group. CONCLUSIONS: The prognosis of patients with IHC(2+)/FISH(+) tumors did not differ from IHC(3+) tumors. However, the significance of HER2 protein overexpression in relation to treatment response remains unclear and warrants further investigations.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , Amplificação de Genes/genética , Expressão Gênica/genética , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Carcinoma/mortalidade , Carcinoma/terapia , Quimioterapia Adjuvante , Feminino , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
19.
Sci Rep ; 12(1): 3122, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210438

RESUMO

Diffuse lower-grade gliomas (LGG) represent the highly heterogeneous and infiltrative neoplasms in the central nervous system (CNS). Replication factor C 2 (RFC2) is a subunit of the RFC complex that modulates DNA replication and repair. However, the prognosis value of RFC2 and its association with the immune signature of tumor microenvironment (TME) in LGG remains unknown. Based on Oncomine, TCGA, GTEx, TIMER, GEPIA, and HPA databases, we evaluated RFC2 expression levels and its clinical prognostic value in LGG and other cancers. Then we analyzed the correlations between RFC2 expression and tumor mutation burden (TMB), tumor microsatellite instability (MSI), and mismatch repair (MMR) genes across cancers. And CIBERSORT and ESTIMATE algorithms were conducted to estimate the association of RFC2 with immune cell infiltration of LGG. Additionally, we performed the functional enrichment analyses of RFC2 in LGG. Then functional experiments were employed to further validate the oncogenic role of RFC2 in LGG. Our results showed that RFC2 was widely highly expressed in most types of cancer. And its expression was closely related to the clinicopathological features and prognosis in LGG and other cancer types. RFC2 levels were also correlated with TMB and MSI across various cancers. Furthermore, RFC2 was positively associated with the infiltration levels of immune cells and immune checkpoint genes in LGG. Additionally, in vitro experiments revealed that RFC2 played an oncogenic role in LGG progression. In conclusion, our findings revealed that RFC2 could serve as a reliable biomarker to predict the prognosis and immune signature for LGG.


Assuntos
Glioma/imunologia , Proteína de Replicação C/metabolismo , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/patologia , China , Biologia Computacional , Bases de Dados Genéticas , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Glioma/patologia , Humanos , Linfócitos do Interstício Tumoral/imunologia , Instabilidade de Microssatélites , Prognóstico , Proteína de Replicação C/genética , Transcriptoma/genética , Microambiente Tumoral/genética
20.
Sci Rep ; 12(1): 2890, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190586

RESUMO

Malignant melanoma is the main cause of death in patients with skin cancer. Overexpression of Proteolipid protein 2 (PLP2) increased tumor metastasis and the knockdown of PLP2 inhibited the growth and metastasis of melanoma cells. In the present work, we studied the antitumor activity of peptide Rb4 derived from protein PLP2. In vitro, Rb4 induced F-actin polymerization, prevented F-actin depolymerization and increased the ER-derived cytosolic calcium. Such effects were associated with necrosis of murine melanoma B16F10-Nex2 cells and with inhibition of the viability of human cancer cell lines. Loss of plasma membrane integrity, dilation of mitochondria, cytoplasm vacuolation and absence of chromatin condensation characterized tumor cell necrosis. Cleavage of PARP-1 and inhibition of RIP1 expression were also observed. In vivo, peptide Rb4 reduced the lung metastasis of tumor cells and delayed the subcutaneous melanoma growth in a syngeneic model. Rb4 induced the expression of two DAMPs molecules, HMGB1 and calreticulin, in B16F10-Nex2. Our results suggest that peptide Rb4 acts directly on tumor cells inducing the expression of DAMPs, which trigger the immunoprotective effect in vivo against melanoma cells. We suggest that peptide Rb4 is a promising compound to be developed as an anticancer drug.


Assuntos
Morte Celular/genética , Expressão Gênica/genética , Expressão Gênica/fisiologia , Proteínas com Domínio MARVEL/genética , Proteínas com Domínio MARVEL/farmacologia , Melanoma/genética , Melanoma/patologia , Poli(ADP-Ribose) Polimerase-1/fisiologia , Proteolipídeos/genética , Proteolipídeos/farmacologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Animais , Antineoplásicos , Calreticulina/genética , Calreticulina/metabolismo , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Humanos , Proteínas com Domínio MARVEL/metabolismo , Proteínas com Domínio MARVEL/fisiologia , Camundongos , Necrose , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Peptídeos , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteolipídeos/metabolismo , Proteolipídeos/fisiologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
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