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1.
Nature ; 593(7859): 429-434, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34012082

RESUMO

Gene-editing technologies, which include the CRISPR-Cas nucleases1-3 and CRISPR base editors4,5, have the potential to permanently modify disease-causing genes in patients6. The demonstration of durable editing in target organs of nonhuman primates is a key step before in vivo administration of gene editors to patients in clinical trials. Here we demonstrate that CRISPR base editors that are delivered in vivo using lipid nanoparticles can efficiently and precisely modify disease-related genes in living cynomolgus monkeys (Macaca fascicularis). We observed a near-complete knockdown of PCSK9 in the liver after a single infusion of lipid nanoparticles, with concomitant reductions in blood levels of PCSK9 and low-density lipoprotein cholesterol of approximately 90% and about 60%, respectively; all of these changes remained stable for at least 8 months after a single-dose treatment. In addition to supporting a 'once-and-done' approach to the reduction of low-density lipoprotein cholesterol and the treatment of atherosclerotic cardiovascular disease (the leading cause of death worldwide7), our results provide a proof-of-concept for how CRISPR base editors can be productively applied to make precise single-nucleotide changes in therapeutic target genes in the liver, and potentially in other organs.


Assuntos
Sistemas CRISPR-Cas , LDL-Colesterol/sangue , Edição de Genes , Modelos Animais , Pró-Proteína Convertase 9/genética , Adenina/metabolismo , Animais , Células Cultivadas , Feminino , Hepatócitos/metabolismo , Humanos , Fígado/enzimologia , Mutação com Perda de Função , Macaca fascicularis/sangue , Macaca fascicularis/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Sítio-Dirigida , Pró-Proteína Convertase 9/sangue , Pró-Proteína Convertase 9/metabolismo , Fatores de Tempo
2.
PLoS Pathog ; 20(1): e1011823, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236820

RESUMO

A variety of coordinated host-cell responses are activated as defense mechanisms against pore-forming toxins (PFTs). Bacillus thuringiensis (Bt) is a worldwide used biopesticide whose efficacy and precise application methods limits its use to replace synthetic pesticides in agricultural settings. Here, we analyzed the intestinal defense mechanisms of two lepidopteran insect pests after intoxication with sublethal dose of Bt PFTs to find out potential functional genes. We show that larval intestinal epithelium was initially damaged by the PFTs and that larval survival was observed after intestinal epithelium regeneration. Further analyses showed that the intestinal regeneration caused by Cry9A protein is regulated through c-Jun NH (2) terminal kinase (JNK) and Janus tyrosine kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways. JAK/STAT signaling regulates intestinal regeneration through proliferation and differentiation of intestinal stem cells to defend three different Bt proteins including Cry9A, Cry1F or Vip3A in both insect pests, Chilo suppressalis and Spodoptera frugiperda. Consequently, a nano-biopesticide was designed to improve pesticidal efficacy based on the combination of Stat double stranded RNA (dsRNA)-nanoparticles and Bt strain. This formulation controlled insect pests with better effect suggesting its potential use to reduce the use of synthetic pesticides in agricultural settings for pest control.


Assuntos
Bacillus thuringiensis , Praguicidas , Animais , Bacillus thuringiensis/genética , Janus Quinases/genética , Tirosina , Endotoxinas/genética , Insetos , Spodoptera/genética , Larva , Praguicidas/farmacologia , Regeneração , Proteínas de Bactérias/farmacologia , Proteínas de Bactérias/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas , Controle Biológico de Vetores/métodos
3.
Nucleic Acids Res ; 52(D1): D426-D433, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933852

RESUMO

The DescribePROT database of amino acid-level descriptors of protein structures and functions was substantially expanded since its release in 2020. This expansion includes substantial increase in the size, scope, and quality of the underlying data, the addition of experimental structural information, the inclusion of new data download options, and an upgraded graphical interface. DescribePROT currently covers 19 structural and functional descriptors for proteins in 273 reference proteomes generated by 11 accurate and complementary predictive tools. Users can search our resource in multiple ways, interact with the data using the graphical interface, and download data at various scales including individual proteins, entire proteomes, and whole database. The annotations in DescribePROT are useful for a broad spectrum of studies that include investigations of protein structure and function, development and validation of predictive tools, and to support efforts in understanding molecular underpinnings of diseases and development of therapeutics. DescribePROT can be freely accessed at http://biomine.cs.vcu.edu/servers/DESCRIBEPROT/.


Assuntos
Aminoácidos , Proteoma , Proteoma/química , Bases de Dados Factuais
4.
Proc Natl Acad Sci U S A ; 120(18): e2218856120, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37094162

RESUMO

The anomalous metallic state (AMS) emerging from a quantum superconductor-to-metal transition is a subject of great current interest since this exotic quantum state exhibits unconventional transport properties that challenge the core physics principles of Fermi liquid theory. As the AMS concept is historically derived from disordered two-dimensional (2D) systems, related studies have predominately concentrated on 2D materials. The AMS behaviors in three-dimensional (3D) systems have been rarely reported to date, which raises intriguing questions on the fundamental nature of pertinent physics. Here, we report experimental evidence for a 3D AMS in highly compressed titanium metal that exhibits superconductivity with a critical temperature (Tc) reaching near-record 25.1 K among elemental superconductors, offering a favorable material template for exploring 3D AMS. At sufficiently strong magnetic fields, unusual transport behaviors set in over a wide pressure range, showcasing AMS hallmarks of a low-temperature saturation resistance below the Drude value and giant positive magnetoresistance. These findings reveal a 3D AMS in simple elemental systems and, more importantly, provide a fresh platform for probing the decades-long enigmatic underlying physics.

5.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653906

RESUMO

Spatially resolved transcriptomics technologies enable comprehensive measurement of gene expression patterns in the context of intact tissues. However, existing technologies suffer from either low resolution or shallow sequencing depth. Here, we present DIST, a deep learning-based method that imputes the gene expression profiles on unmeasured locations and enhances the gene expression for both original measured spots and imputed spots by self-supervised learning and transfer learning. We evaluate the performance of DIST for imputation, clustering, differential expression analysis and functional enrichment analysis. The results show that DIST can impute the gene expression accurately, enhance the gene expression for low-quality data, help detect more biological meaningful differentially expressed genes and pathways, therefore allow for deeper insights into the biological processes.


Assuntos
Aprendizado Profundo , Transcriptoma , Perfilação da Expressão Gênica/métodos , Análise por Conglomerados
6.
Hepatology ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38377452

RESUMO

BACKGROUND AND AIMS: Protein tyrosine sulfation (PTS) is a common posttranslational modification that regulates a variety of physiological and pathological processes. However, the role of PTS in cancer remains poorly understood. The goal of this study was to determine whether and how PTS plays a role in HCC progression. APPROACH AND RESULTS: By mass spectrometry and bioinformatics analysis, we identified SAV1 as a novel substrate of PTS in HCC. Oxidative stress upregulates the transcription of SLC35B2, a Golgi-resident transporter of sulfate donor 3'-phosphoadenosine 5'-phosphosulfate, leading to increased sulfation of SAV1. Sulfation of SAV1 disrupts the formation of the SAV1-MST1 complex, resulting in a decrease of MST1 phosphorylation and subsequent inactivation of Hippo signaling. These molecular events ultimately foster the growth of HCC cells both in vivo and in vitro. Moreover, SLC35B2 is a novel transcription target gene of the Hippo pathway, constituting a positive feedback loop that facilitates HCC progression under oxidative stress. CONCLUSIONS: Our findings reveal a regulatory mechanism of the SLC35B2/SAV1 sulfation axis in response to oxidative stress, highlighting its potential as a promising therapeutic target for HCC.

7.
Plant Physiol ; 195(1): 598-616, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38319742

RESUMO

Chinese bayberry (Morella rubra) is a fruit tree with a remarkable variation in fruit color, ranging from white to dark red as determined by anthocyanin content. In dark red "Biqi" (BQ), red "Dongkui" (DK), pink "Fenhong" (FH), and white "Shuijing" (SJ), we identified an anthocyanin-related MYB transcription factor-encoding gene cluster of four members, i.e. MrMYB1.1, MrMYB1.2, MrMYB1.3, and MrMYB2. Collinear analysis revealed that the MYB tandem cluster may have occurred in a highly conserved region of many eudicot genomes. Two alleles of MrMYB1.1 were observed; MrMYB1.1-1 (MrMYB1.1n) was a full-length allele and homozygous in "BQ", MrMYB1.1-2 (MrMYB1.1d) was a nonfunctional allele with a single base deletion and homozygous in "SJ", and MrMYB1.1n/MrMYB1.1d were heterozygous in "DK" and "FH". In these four cultivars, expression of MrMYB1.1, MrMYB1.2, and MrMYB2 was enhanced during ripening. Both alleles were equally expressed in MrMYB1.1n/MrMYB1.1d heterozygous cultivars as revealed by a cleaved amplified polymorphic sequence marker. Expression of MrMYB1.3 was restricted to some dark red cultivars only. Functional characterization revealed that MrMYB1.1n and MrMYB1.3 can induce anthocyanin accumulation while MrMYB1.1d, MrMYB1.2, and MrMYB2 cannot. DNA-protein interaction assays indicated that MrMYB1.1n and MrMYB1.3 can directly bind to and activate the promoters of anthocyanin-related genes via interaction with a MYC-like basic helix-loop-helix protein MrbHLH1. We concluded that the specific genotype of MrMYB1.1 alleles, as well as the exclusive expression of MrMYB1.3 in some dark red cultivars, contributes to fruit color variation. The study provides insights into the mechanisms for regulation of plant anthocyanin accumulation by MYB tandem clusters.


Assuntos
Frutas , Regulação da Expressão Gênica de Plantas , Família Multigênica , Pigmentação , Proteínas de Plantas , Fatores de Transcrição , Frutas/genética , Frutas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pigmentação/genética , Antocianinas/metabolismo , Filogenia , Alelos , Genes de Plantas , Dados de Sequência Molecular , Sequência de Aminoácidos , Cor
8.
Mol Ther ; 32(10): 3580-3596, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39217416

RESUMO

Programmed death-ligand 1 (PD-L1) on tumor-derived small extracellular vesicles (sEVs) limits therapeutic effectiveness by interacting with the PD-1 receptor on host immune cells. Targeting the secretion of sEV PD-L1 has emerged as a promising strategy to enhance immunotherapy. However, the lack of small-molecule inhibitors poses a challenge for clinical translation. In this study, we developed a target and phenotype dual-driven high-throughput screening strategy that combined virtual screening with nanoflow-based experimental verification. We identified ibuprofen (IBP) as a novel inhibitor that effectively targeted sEV PD-L1 secretion. IBP disrupted the biogenesis and secretion of PD-L1+ sEVs in tumor cells by physically interacting with a critical regulator of sEV biogenesis, hepatocyte growth factor-regulated tyrosine kinase substrate. Notably, the mechanism of action of IBP is distinct from its commonly known targets, cyclooxygenases. Administration of IBP stimulated antitumor immunity and enhanced the efficacy of anti-PD-1 therapy in melanoma and oral squamous cell carcinoma mouse models. To address potential adverse effects, we further developed an IBP gel for topical application, which demonstrated remarkable therapeutic efficacy when combined with anti-PD-1 treatment. The discovery of this specific small inhibitor provides a promising avenue for establishing durable, systemic antitumor immunity.


Assuntos
Antígeno B7-H1 , Vesículas Extracelulares , Ensaios de Triagem em Larga Escala , Ibuprofeno , Imunoterapia , Animais , Camundongos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Humanos , Ensaios de Triagem em Larga Escala/métodos , Ibuprofeno/farmacologia , Imunoterapia/métodos , Linhagem Celular Tumoral , Vesículas Extracelulares/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/terapia , Modelos Animais de Doenças , Sinergismo Farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Mol Cell Cardiol ; 186: 45-56, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979444

RESUMO

Cardiac hypertrophy can develop to end-stage heart failure (HF), which inevitably leading to heart transplantation or death. Preserving cardiac function in cardiomyocytes (CMs) is essential for improving prognosis in hypertrophic cardiomyopathy (HCM) patients. Therefore, understanding transcriptomic heterogeneity of CMs in HCM would be indispensable to aid potential therapeutic targets investigation. We isolated primary CM from HCM patients who had extended septal myectomy, and obtained transcriptomes in 338 human primary CM with single-cell tagged reverse transcription (STRT-seq) approach. Our results revealed that CMs could be categorized into three subsets in nonfailing HCM heart: high energy synthesis cluster, high cellular metabolism cluster and intermediate cluster. The expression of electron transport chain (ETC) was up-regulated in larger-sized CMs from high energy synthesis cluster. Of note, we found the expression of Cytochrome c oxidase subunit 7B (COX7B), a subunit of Complex IV in ETC had trends of positively correlation with CMs size. Further, by assessing COX7B expression in HCM patients, we speculated that COX7B was compensatory up-regulated at early-stage but down-regulated in failing HCM heart. To test the hypothesis that COX7B might participate both in hypertrophy and HF progression, we used adeno associated virus 9 (AAV9) to mediate the expression of Cox7b in pressure overload-induced mice. Mice in vivo data supported that knockdown of Cox7b would accelerate HF and Cox7b overexpression could restore partial cardiac function in hypertrophy. Our result highlights targeting COX7B and preserving energy synthesis in hypertrophic CMs could be a promising translational direction for HF therapeutic strategy.


Assuntos
Cardiomiopatia Hipertrófica , Insuficiência Cardíaca , Transplante de Coração , Humanos , Animais , Camundongos , Miócitos Cardíacos/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Cardiomiopatia Hipertrófica/metabolismo , Cardiomegalia/genética , Cardiomegalia/metabolismo
10.
Int J Cancer ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39450706

RESUMO

Serum hepatitis B core-related antigen (HBcrAg) is considered a surrogate marker of the amount and activity of intrahepatic covalently closed circular DNA. This study aimed to explore the prognostic value of HBcrAg on patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) after curative hepatectomy undergoing antiviral therapy (AVT). Data of 949 consecutive patients with HBV-related HCC undergoing curative resection between 2010 and 2013 were reviewed. Serum HBcrAg levels were measured at surgery (baseline) for all patients and at the time of 2 years postoperatively (on-treatment) for those without recurrence. Primary endpoint was tumor recurrence. High HBcrAg levels are associated with malignant phenotypes. HBcrAg independently affected both recurrence and overall survival (OS) in patients with negative hepatitis B e antigen (HBeAg-, p = .007 and p = .042, respectively) but not in their positive HBeAg (HBeAg+) counterparts (p = .100 and p = .075, respectively). Patients with high baseline HBcrAg had higher late, but not early recurrence rates than those with low baseline HBcrAg levels, regardless of HBeAg status (HBeAg+: p = .307 for early, p = .001 for late; HBeAg-: p = .937 for early, p < .001 for late). On-treatment HBcrAg independently affected late recurrence in patients stratified by both cirrhosis and HBeAg (p < .001 for all). The predictive power of HBcrAg kinetics for late recurrence was better than that of the baseline and on-treatment HBcrAg. High HBcrAg levels during long-term AVT are associated with late recurrence of HCC after hepatectomy. Combining baseline and on-treatment HBcrAg might be valuable in identifying patients at a high risk of relapse and stratifying surveillance strategies postoperatively.

11.
Oncologist ; 29(4): e487-e497, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37874924

RESUMO

BACKGROUND: The difference in the prognoses between treatment with surgical therapy and continuation of local-plus-systemic therapy following successful down-staging of intermediate-advanced hepatocellular carcinoma (HCC) remains unclear. METHODS: Data of 405 patients with intermediate-advanced HCC treated at 30 hospitals across China from January 2017 to July 2022 were retrospectively reviewed. All patients received local-plus-systemic therapy and were divided into the surgical (n = 100) and nonsurgical groups (n = 305) according to whether they received surgical therapy. The differences between long-term prognoses of the 2 groups were compared. Subgroup analysis was performed in 173 HCC patients who met the criteria for surgical resection following down-staging. RESULTS: Multivariable analysis of all patients showed that surgical therapy, hazard ratio (HR): 0.289, 95% confidence interval, CI, 0.136-0.613) was a protective factor for overall survival (OS), but not for event-free survival (EFS). Multivariable analysis of 173 intermediate-advanced HCC patients who met the criteria for surgical resection after conversion therapy showed that surgical therapy (HR: 0.282, 95% CI, 0.121-0.655) was a protective factor for OS, but not for EFS. Similar results were obtained after propensity score matching. For patients with Barcelona Clinic Liver Cancer stage B (HR: 0.171, 95% CI, 0.039-0.751) and C (HR: 0.269, 95% CI, 0.085-0.854), surgical therapy was also a protective factor for OS. CONCLUSIONS: Overall, for patients with intermediate-advanced HCC who underwent local-plus-systemic therapies, surgical therapy is a protective factor for long-term prognosis and can prolong OS, and for those who met the surgical resection criteria after conversion therapy, surgical therapy is recommended.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Prognóstico , Hepatectomia
12.
Anal Chem ; 96(35): 14125-14132, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-38978161

RESUMO

Mitochondrial DNA (mtDNA) is a unique genetic material characterized by maternal inheritance. It possesses a circular structure devoid of histone protection and exhibits low cellular abundance, which poses great challenges for its sensitive and selective detection at the living cell level. Herein, we have designed three bis-naphthylimide probes with varying linker lengths (NANn-OH, n = 0, 2, 6), facilitating the formation of distinct twisted or folded molecular conformations in the free state. These probes emit the red fluorescence around 627 nm with different fluorescence quantum yields (ΦNAN0-OH = 0.0016, ΦNAN2-OH = 0.0136, and ΦNAN6-OH = 0.0125). When encountering mtDNA (0.4-3.4 µg/mL), these probes undergo conformational changes depending on the length of the attached C-strand and exhibit a gradually increasing fluorescence signal around 453 nm. The fluorescence intensity increased to 13.5-fold, 1.9-fold, and 8.2-fold, respectively. Notably, the red fluorescence intensities around 627 nm remain constant throughout this process, thus serving as an inherent correction mechanism for proportional fluorescence signal enhancement to improve selectivity and sensitivity. NAN0-OH, NAN2-OH, and NAN6-OH showed good linearity for mtDNA in the range of 0.4-3.4 µg/mL with detection limits of LODNAN0-OH = 1.04 µg/mL, LODNAN2-OH = 1.10 µg/mL, and LODNAN6-OH = 1.15 µg/mL. Cellular experiments reveal that NAN6-OH effectively monitors curcumin-induced mtDNA damage in HepG-2 cells while enabling monitoring of genetic mtDNA damage. We anticipate that this tool holds significant potential for the precise evaluation of maternal genetic defects, thereby enhancing hypersensitive assessment in clinical medicine.


Assuntos
DNA Mitocondrial , Corantes Fluorescentes , Espectrometria de Fluorescência , Humanos , DNA Mitocondrial/genética , Corantes Fluorescentes/química , Fluorescência , Limite de Detecção , Naftalimidas/química
13.
J Gene Med ; 26(5): e3689, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38676365

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive malignancy characterized by a poor prognosis and closely linked to tumor stemness. However, the key molecules that regulate ICC stemness remain elusive. Although Y-box binding protein 1 (YBX1) negatively affects prognosis in various cancers by enhancing stemness and chemoresistance, its effect on stemness and cisplatin sensitivity in ICC remains unclear. METHODS: Three bulk and single-cell RNA-seq datasets were analyzed to investigate YBX1 expression in ICC and its association with stemness. Clinical samples and colony/sphere formation assays validated the role of YBX1 in stemness and sensitivity to cisplatin. AZD5363 and KYA1979K explored the interaction of YBX1 with the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB/AKT) and WNT/ß-catenin pathways. RESULTS: YBX1 was significantly upregulated in ICC, correlated with worse overall survival and shorter postoperative recurrence time, and was higher in chemotherapy-non-responsive ICC tissues. The YBX1-high group exhibited significantly elevated stemness scores, and genes linked to YBX1 upregulation were enriched in multiple stemness-related pathways. Moreover, YBX1 expression is significantly correlated with several stemness-related genes (SOX9, OCT4, CD133, CD44 and EPCAM). Additionally, YBX1 overexpression significantly enhanced the colony- and spheroid-forming abilities of ICC cells, accelerated tumor growth in vivo and reduced their sensitivity to cisplatin. Conversely, the downregulation of YBX1 exerted the opposite effect. The transcriptomic analysis highlighted the link between YBX1 and the PI3K/AKT and WNT/ß-catenin pathways. Further, AZD5363 and KYA1979K were used to clarify that YBX1 promoted ICC stemness through the regulation of the AKT/ß-catenin axis. CONCLUSIONS: YBX1 is upregulated in ICC and promotes stemness and cisplatin insensitivity via the AKT/ß-catenin axis. Our study describes a novel potential therapeutic target for improving ICC prognosis.


Assuntos
Colangiocarcinoma , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Proteína 1 de Ligação a Y-Box , beta Catenina , Animais , Feminino , Humanos , Masculino , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , beta Catenina/metabolismo , beta Catenina/genética , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Colangiocarcinoma/mortalidade , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína 1 de Ligação a Y-Box/metabolismo , Proteína 1 de Ligação a Y-Box/genética
14.
Genome Res ; 31(10): 1753-1766, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34035047

RESUMO

Recent developments of single-cell RNA-seq (scRNA-seq) technologies have led to enormous biological discoveries. As the scale of scRNA-seq studies increases, a major challenge in analysis is batch effects, which are inevitable in studies involving human tissues. Most existing methods remove batch effects in a low-dimensional embedding space. Although useful for clustering, batch effects are still present in the gene expression space, leaving downstream gene-level analysis susceptible to batch effects. Recent studies have shown that batch effect correction in the gene expression space is much harder than in the embedding space. Methods such as Seurat 3.0 rely on the mutual nearest neighbor (MNN) approach to remove batch effects in gene expression, but MNN can only analyze two batches at a time, and it becomes computationally infeasible when the number of batches is large. Here, we present CarDEC, a joint deep learning model that simultaneously clusters and denoises scRNA-seq data while correcting batch effects both in the embedding and the gene expression space. Comprehensive evaluations spanning different species and tissues showed that CarDEC outperforms Scanorama, DCA + Combat, scVI, and MNN. With CarDEC denoising, non-highly variable genes offer as much signal for clustering as the highly variable genes (HVGs), suggesting that CarDEC substantially boosted information content in scRNA-seq. We also showed that trajectory analysis using CarDEC's denoised and batch-corrected expression as input revealed marker genes and transcription factors that are otherwise obscured in the presence of batch effects. CarDEC is computationally fast, making it a desirable tool for large-scale scRNA-seq studies.


Assuntos
Aprendizado Profundo , Transcriptoma , Algoritmos , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos
15.
Small ; : e2407216, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39473292

RESUMO

The electrochemical nitrate reduction reaction (NO3RR), which converts harmful nitrates into valuable ammonia (NH3) with zero carbon emission, is one of the most promising alternatives to the Haber-Bosch process. However, the NO3RR process is complex and involves multiple proton-coupled electron transfers that generate intermediates or byproducts, such as NO2 -, resulting in low ammonia yields and faradaic efficiency (FE). Herein, by constructing a FeCu bimetallic catalyst (FeCu-NC), the hydrogenation position of *NO3 is switched at the FeCu dual-atom site, preventing the desorption of *NO2 intermediate. Furthermore, electron transfer from Cu to Fe sites mimics the electron flow direction in natural nitrite reductase enzymes and accelerates the reduction of *NO2 to NH3, achieving efficient conversion of NO3 - to NH3. A 24-hour electrocatalytic experiment with FeCu-NC demonstrates negligible NO2 - formation throughout the NO3RR process, with an ammonia production rate of 6.13 mg h-1 mgcat -1 and an impressive FE of 95%, which are remarkably superior in comparison to most of the NO3RR electrocatalysts. This work opens new avenues for the fundamental understanding of catalytic mechanisms and the development of next-generation catalysts for sustainable ammonia production.

16.
Plant Biotechnol J ; 22(6): 1468-1490, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38169146

RESUMO

Variation in anthocyanin biosynthesis in pear fruit provides genetic germplasm resources for breeding, while dwarfing is an important agronomic trait, which is beneficial to reduce the management costs and allow for the implementation of high-density cultivation. Here, we combined bulked segregant analysis (BSA), quantitative trait loci (QTL), and structural variation (SV) analysis to identify a 14-bp deletion which caused a frame shift mutation and resulted in the premature translation termination of a B-box (BBX) family of zinc transcription factor, PyBBX24, and its allelic variation termed PyBBX24ΔN14. PyBBX24ΔN14 overexpression promotes anthocyanin biosynthesis in pear, strawberry, Arabidopsis, tobacco, and tomato, while that of PyBBX24 did not. PyBBX24ΔN14 directly activates the transcription of PyUFGT and PyMYB10 through interaction with PyHY5. Moreover, stable overexpression of PyBBX24ΔN14 exhibits a dwarfing phenotype in Arabidopsis, tobacco, and tomato plants. PyBBX24ΔN14 can activate the expression of PyGA2ox8 via directly binding to its promoter, thereby deactivating bioactive GAs and reducing the plant height. However, the nuclear localization signal (NLS) and Valine-Proline (VP) motifs in the C-terminus of PyBBX24 reverse these effects. Interestingly, mutations leading to premature termination of PyBBX24 were also identified in red sports of un-related European pear varieties. We conclude that mutations in PyBBX24 gene link both an increase in pigmentation and a decrease in plant height.


Assuntos
Proteínas de Plantas , Pyrus , Alelos , Antocianinas/metabolismo , Frutas/genética , Frutas/metabolismo , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Nicotiana/genética , Nicotiana/metabolismo , Fenótipo , Pigmentação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Pyrus/genética , Pyrus/metabolismo , Pyrus/crescimento & desenvolvimento , Locos de Características Quantitativas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Brief Bioinform ; 23(4)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35821114

RESUMO

Developments of single-cell RNA sequencing (scRNA-seq) technologies have enabled biological discoveries at the single-cell resolution with high throughput. However, large scRNA-seq datasets always suffer from massive technical noises, including batch effects and dropouts, and the dropout is often shown to be batch-dependent. Most existing methods only address one of the problems, and we show that the popularly used methods failed in trading off batch effect correction and dropout imputation. Here, inspired by the idea of causal inference, we propose a novel propensity score matching method for scRNA-seq data (scPSM) by borrowing information and taking the weighted average from similar cells in the deep sequenced batch, which simultaneously removes the batch effect, imputes dropout and denoises data in the entire gene expression space. The proposed method is testified on two simulation datasets and a variety of real scRNA-seq datasets, and the results show that scPSM is superior to other state-of-the-art methods. First, scPSM improves clustering accuracy and mixes cells of the same type, suggesting its ability to keep cell type separation while correcting for batch. Besides, using the scPSM-integrated data as input yields results free of batch effects or dropouts in the differential expression analysis. Moreover, scPSM not only achieves ideal denoising but also preserves real biological structure for downstream gene-based analyses. Furthermore, scPSM is robust to hyperparameters and small datasets with a few cells but enormous genes. Comprehensive evaluations demonstrate that scPSM jointly provides desirable batch effect correction, imputation and denoising for recovering the biologically meaningful expression in scRNA-seq data.


Assuntos
Perfilação da Expressão Gênica , Análise de Célula Única , Análise por Conglomerados , Pontuação de Propensão , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Software
18.
Plant Cell Environ ; 47(12): 4833-4848, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39101482

RESUMO

Peach varieties that differ in red coloration due to varied anthocyanin accumulation result from transcriptional regulation by PpMYB10s, a group of specific R2R3 MYBs. Here we investigated the mechanisms driving a lack of anthocyanin in yellow-skinned 'Jinxiu' peach peel, as well as accumulation induced by UV irradiance. It was found that PpMYB10.1, PpMYB10.2 and PpMYB10.3 were positive regulators of anthocyanin accumulation, but the stimulation by PpMYB10.2 was weak. Low expression of PpMYB10.1 causes natural anthocyanin deficiency in 'Jinxiu' peel. However, the promoter sequences of PpMYB10.1 were identical in 'Jinxiu' and a naturally red-coloured peach 'Hujingmilu'. Therefore, potential negative regulator(s) upstream of PpMYB10.1 were explored. A novel R2R3-MYB repressor termed PpMYB80 was identified through comparative transcriptomic analysis and then functionally confirmed via transiently overexpressing and silencing in peach fruit, as well as transformation in tobacco. PpMYB80 directly binds to the promoter of PpMYB10.1 and inhibits its expression, but does not affect PpMYB10.3. In UV-exposed 'Jinxiu' fruit, expression of PpMYB10.3 was upregulated, while PpMYB10.1 remained low and PpMYB80 enhanced, which results in accumulation of anthocyanin in peel. This study revealed a transcriptional cascade involving PpMYB activators and repressors in regulating basal and UV-induced anthocyanin accumulation in peach peel.


Assuntos
Antocianinas , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Prunus persica , Raios Ultravioleta , Antocianinas/metabolismo , Prunus persica/genética , Prunus persica/metabolismo , Prunus persica/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Frutas/metabolismo , Frutas/genética , Frutas/efeitos da radiação , Regiões Promotoras Genéticas/genética , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/efeitos da radiação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Plantas Geneticamente Modificadas
19.
BMC Cancer ; 24(1): 1106, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237882

RESUMO

BACKGROUND: This study aims to investigate preoperative prognostic factors available for intrahepatic cholangiocarcinoma (ICC) patients and propose a new preoperative prognostic scoring system for ICC that combines CA19-9 and neutrophil/lymphocyte ratio (NLR). METHODS: In this retrospective analysis, 1728 patients diagnosed with ICC and undergoing curative liver resections were studied. This study employed univariate and multivariate Cox regression to find factors affecting recurrence and overall survival (OS), and furthermore assessed how preoperative models influenced tumor traits and postoperative recurrence. RESULTS: The results of the multivariate Cox regression analysis indicated that two preoperative variables, NLR and Ca19-9, were independent risk factors affecting postoperative recurrence and OS in ICC patients. Based on this data, assigning a score of 0 (NLR ≤ 2.4 and Ca19-9 ≤ 37U/ml) or 1 (NLR > 2.4 and Ca19-9 > 37U/ml) to these two factors, a preoperative prognostic score was derived. According to the scoring model, patients were divided into three groups: 0 points (low-risk group), 1 point (intermediate-risk group), and 2 points (high-risk group). The 5-year recurrence and OS rates for the three groups were 56.6%, 68.2%, 77.8%, and 56.8%, 40.6%, 27.6%, respectively, with all P values < 0.001. Furthermore, high-risk group patients were more prone to early recurrence (early recurrence rates for high-, intermediate-, and low-risk groups were 56.8%, 51.5%, and 37.1%, respectively, P < 0.001) and extrahepatic metastasis (extrahepatic metastasis rates for high-, intermediate-, and low-risk groups were 31.7%, 26.4%, and 15.4%, respectively, P < 0.001). In terms of tumor characteristics, high-risk group patients had larger tumor diameters and were more likely to experience microvascular invasion, lymph node metastasis, and perineural invasion. CONCLUSIONS: The predictive capacity of postoperative recurrence and OS rates in ICC patients is effectively captured by the preoperative scoring system incorporating NLR and CA19-9 levels.


Assuntos
Neoplasias dos Ductos Biliares , Antígeno CA-19-9 , Colangiocarcinoma , Hepatectomia , Linfócitos , Recidiva Local de Neoplasia , Neutrófilos , Humanos , Colangiocarcinoma/cirurgia , Colangiocarcinoma/sangue , Colangiocarcinoma/patologia , Colangiocarcinoma/mortalidade , Masculino , Feminino , Neutrófilos/patologia , Pessoa de Meia-Idade , Prognóstico , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/mortalidade , Estudos Retrospectivos , Linfócitos/patologia , Antígeno CA-19-9/sangue , Idoso , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Adulto , Período Pré-Operatório , Contagem de Linfócitos , Fatores de Risco
20.
BMC Cancer ; 24(1): 358, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509498

RESUMO

BACKGROUND: The prognostic significance of tumor burden score (TBS) in relation to carcinoembryonic antigen (CEA) has not been investigated among patients undergoing hepatectomy for intrahepatic cholangiocarcinoma (ICC). This study aimed to develop and validate a simplified model, a combination of TBS and CEA (CTC grade), for predicting the long-term outcomes of postoperative ICC patients. METHODS: Patients who underwent curative - intent resection of ICC between 2011 and 2019 were identified from a large multi - institutional database. The impact of TBS, CEA, and the CTC grade on overall survival (OS) and recurrence - free survival (RFS) was evaluated in both the derivation and validation cohorts. The receiver operating characteristic curve was utilized for assessing the predictive accuracy of the model. Subgroup analyses were performed across 8th TNM stage system stratified by CTC grade to assess the discriminatory capacity within the same TNM stage. RESULTS: A total of 812 patients were included in the derivation cohort and 266 patients in the validation cohort. Survival varied based on CEA (low: 36.7% vs. high: 9.0%) and TBS (low: 40.3% vs. high: 17.6%) in relation to 5 - year survival (both p < 0.001). As expected, patients with low CTC grade (i.e., low TBS/low CEA) were associated with the best OS as well as RFS, while high CTC grade (i.e., high TBS/high CEA) correlated to the worst outcomes. The model exhibited well performance in both the derivation cohort (area under the curve of 0.694) and the validation cohort (0.664). The predictive efficacy of the CTC grade system remains consistently stable across TNM stages I and III/IV. CONCLUSION: The CTC grade, a composite parameter derived from the combination of TBS and CEA levels, served as an easy - to - use tool and performed well in stratifying patients with ICC relative to OS and RFS.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Hepatectomia , Antígeno Carcinoembrionário , Carga Tumoral , Colangiocarcinoma/patologia , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Estudos Retrospectivos
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