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1.
Cell ; 157(4): 979-991, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24813617

RESUMO

The reprogramming of parental methylomes is essential for embryonic development. In mammals, paternal 5-methylcytosines (5mCs) have been proposed to be actively converted to oxidized bases. These paternal oxidized bases and maternal 5mCs are believed to be passively diluted by cell divisions. By generating single-base resolution, allele-specific DNA methylomes from mouse gametes, early embryos, and primordial germ cell (PGC), as well as single-base-resolution maps of oxidized cytosine bases for early embryos, we report the existence of 5hmC and 5fC in both maternal and paternal genomes and find that 5mC or its oxidized derivatives, at the majority of demethylated CpGs, are converted to unmodified cytosines independent of passive dilution from gametes to four-cell embryos. Therefore, we conclude that paternal methylome and at least a significant proportion of maternal methylome go through active demethylation during embryonic development. Additionally, all the known imprinting control regions (ICRs) were classified into germ-line or somatic ICRs.


Assuntos
Metilação de DNA , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Impressão Genômica , 5-Metilcitosina/metabolismo , Animais , Ilhas de CpG , Citosina/análogos & derivados , Citosina/metabolismo , Embrião de Mamíferos/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Regiões Promotoras Genéticas
2.
Nat Rev Genet ; 23(7): 395-410, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35217821

RESUMO

The development of single-cell and spatial transcriptomics methods was instrumental in the conception of the Human Cell Atlas initiative, which aims to generate an integrated map of all cells across the human body. These technology advances are bringing increasing depth and resolution to maps of human organs and tissues, as well as our understanding of individual human cell types. Commonalities as well as tissue-specific features of primary and supportive cell types across human organs are beginning to emerge from these human tissue maps. In this Review, we highlight key biological insights obtained from cross-tissue studies into epithelial, fibroblast, vascular and immune cells based on single-cell gene expression data in humans and contrast it with mechanisms reported in mice.


Assuntos
Análise de Célula Única , Transcriptoma , Animais , Humanos , Camundongos
3.
Nature ; 601(7892): 257-262, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937940

RESUMO

The methanogenic degradation of oil hydrocarbons can proceed through syntrophic partnerships of hydrocarbon-degrading bacteria and methanogenic archaea1-3. However, recent culture-independent studies have suggested that the archaeon 'Candidatus Methanoliparum' alone can combine the degradation of long-chain alkanes with methanogenesis4,5. Here we cultured Ca. Methanoliparum from a subsurface oil reservoir. Molecular analyses revealed that Ca. Methanoliparum contains and overexpresses genes encoding alkyl-coenzyme M reductases and methyl-coenzyme M reductases, the marker genes for archaeal multicarbon alkane and methane metabolism. Incubation experiments with different substrates and mass spectrometric detection of coenzyme-M-bound intermediates confirm that Ca. Methanoliparum thrives not only on a variety of long-chain alkanes, but also on n-alkylcyclohexanes and n-alkylbenzenes with long n-alkyl (C≥13) moieties. By contrast, short-chain alkanes (such as ethane to octane) or aromatics with short alkyl chains (C≤12) were not consumed. The wide distribution of Ca. Methanoliparum4-6 in oil-rich environments indicates that this alkylotrophic methanogen may have a crucial role in the transformation of hydrocarbons into methane.


Assuntos
Euryarchaeota , Hidrocarbonetos , Metano , Alcanos/metabolismo , Biodegradação Ambiental , Euryarchaeota/enzimologia , Euryarchaeota/genética , Hidrocarbonetos/metabolismo , Metano/metabolismo , Oxirredutases/metabolismo , Filogenia
4.
Plant Cell ; 36(8): 2893-2907, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38735686

RESUMO

Increasing grain yield is a major goal of breeders due to the rising global demand for food. We previously reported that the miR397-LACCASE (OsLAC) module regulates brassinosteroid (BR) signaling and grain yield in rice (Oryza sativa). However, the precise roles of laccase enzymes in the BR pathway remain unclear. Here, we report that OsLAC controls grain yield by preventing the turnover of TRANSTHYRETIN-LIKE (OsTTL), a negative regulator of BR signaling. Overexpressing OsTTL decreased BR sensitivity in rice, while loss-of-function of OsTTL led to enhanced BR signaling and increased grain yield. OsLAC directly binds to OsTTL and regulates its phosphorylation-mediated turnover. The phosphorylation site Ser226 of OsTTL is essential for its ubiquitination and degradation. Overexpressing the dephosphorylation-mimic form of OsTTL (OsTTLS226A) resulted in more severe defects than did overexpressing OsTTL. These findings provide insight into the role of an ancient laccase in BR signaling and suggest that the OsLAC-OsTTL module could serve as a target for improving grain yield.


Assuntos
Regulação da Expressão Gênica de Plantas , Lacase , MicroRNAs , Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/enzimologia , Lacase/metabolismo , Lacase/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Fosforilação , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/genética , Grão Comestível/metabolismo , Transdução de Sinais , Plantas Geneticamente Modificadas , Brassinosteroides/metabolismo
5.
Nature ; 591(7850): 431-437, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33505021

RESUMO

Lysosomes have fundamental physiological roles and have previously been implicated in Parkinson's disease1-5. However, how extracellular growth factors communicate with intracellular organelles to control lysosomal function is not well understood. Here we report a lysosomal K+ channel complex that is activated by growth factors and gated by protein kinase B (AKT) that we term lysoKGF. LysoKGF consists of a pore-forming protein TMEM175 and AKT: TMEM175 is opened by conformational changes in, but not the catalytic activity of, AKT. The minor allele at rs34311866, a common variant in TMEM175, is associated with an increased risk of developing Parkinson's disease and reduces channel currents. Reduction in lysoKGF function predisposes neurons to stress-induced damage and accelerates the accumulation of pathological α-synuclein. By contrast, the minor allele at rs3488217-another common variant of TMEM175, which is associated with a decreased risk of developing Parkinson's disease-produces a gain-of-function in lysoKGF during cell starvation, and enables neuronal resistance to damage. Deficiency in TMEM175 leads to a loss of dopaminergic neurons and impairment in motor function in mice, and a TMEM175 loss-of-function variant is nominally associated with accelerated rates of cognitive and motor decline in humans with Parkinson's disease. Together, our studies uncover a pathway by which extracellular growth factors regulate intracellular organelle function, and establish a targetable mechanism by which common variants of TMEM175 confer risk for Parkinson's disease.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Lisossomos/metabolismo , Complexos Multiproteicos/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Canais de Potássio/metabolismo , Potássio/metabolismo , Animais , Biocatálise , Neurônios Dopaminérgicos/metabolismo , Feminino , Mutação com Ganho de Função , Células HEK293 , Humanos , Mutação com Perda de Função , Masculino , Camundongos , Camundongos Knockout , Destreza Motora , Complexos Multiproteicos/química , Complexos Multiproteicos/deficiência , Complexos Multiproteicos/genética , Doença de Parkinson/genética , Canais de Potássio/química , Canais de Potássio/deficiência , Canais de Potássio/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , alfa-Sinucleína/metabolismo
6.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38261339

RESUMO

Various methods have been proposed to reconstruct admixture histories by analyzing the length of ancestral chromosomal tracts, such as estimating the admixture time and number of admixture events. However, available methods do not explicitly consider the complex admixture structure, which characterizes the joining and mixing patterns of different ancestral populations during the admixture process, and instead assume a simplified one-by-one sequential admixture model. In this study, we proposed a novel approach that considers the non-sequential admixture structure to reconstruct admixture histories. Specifically, we introduced a hierarchical admixture model that incorporated four ancestral populations and developed a new method, called HierarchyMix, which uses the length of ancestral tracts and the number of ancestry switches along genomes to reconstruct the four-way admixture history. By automatically selecting the optimal admixture model using the Bayesian information criterion principles, HierarchyMix effectively estimates the corresponding admixture parameters. Simulation studies confirmed the effectiveness and robustness of HierarchyMix. We also applied HierarchyMix to Uyghurs and Kazakhs, enabling us to reconstruct the admixture histories of Central Asians. Our results highlight the importance of considering complex admixture structures and demonstrate that HierarchyMix is a useful tool for analyzing complex admixture events.


Assuntos
População da Ásia Central , Genética Populacional , Humanos , Teorema de Bayes , População da Ásia Central/genética , Simulação por Computador , Cromossomos/genética , Genética Populacional/métodos
7.
Proc Natl Acad Sci U S A ; 120(8): e2206694120, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36795754

RESUMO

Notch has been implicated in human cancers and is a putative therapeutic target. However, the regulation of Notch activation in the nucleus remains largely uncharacterized. Therefore, characterizing the detailed mechanisms governing Notch degradation will identify attractive strategies for treating Notch-activated cancers. Here, we report that the long noncoding RNA (lncRNA) BREA2 drives breast cancer metastasis by stabilizing the Notch1 intracellular domain (NICD1). Moreover, we reveal WW domain containing E3 ubiquitin protein ligase 2 (WWP2) as an E3 ligase for NICD1 at K1821 and a suppressor of breast cancer metastasis. Mechanistically, BREA2 impairs WWP2-NICD1 complex formation and in turn stabilizes NICD1, leading to Notch signaling activation and lung metastasis. BREA2 loss sensitizes breast cancer cells to inhibition of Notch signaling and suppresses the growth of breast cancer patient-derived xenograft tumors, highlighting its therapeutic potential in breast cancer. Taken together, these results reveal the lncRNA BREA2 as a putative regulator of Notch signaling and an oncogenic player driving breast cancer metastasis.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , RNA Longo não Codificante , Humanos , Feminino , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Neoplasias Pulmonares/genética , Neoplasias da Mama/genética , Receptor Notch1/genética , Receptor Notch1/metabolismo
8.
Trends Genet ; 38(10): 1019-1047, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35811173

RESUMO

Gene regulation by transcriptional enhancers is the dominant mechanism driving cell type- and signal-specific transcriptional diversity in metazoans. However, over four decades since the original discovery, how enhancers operate in the nuclear space remains largely enigmatic. Recent multidisciplinary efforts combining real-time imaging, genome sequencing, and biophysical strategies provide insightful but conflicting models of enhancer-mediated gene control. Here, we review the discovery and progress in enhancer biology, emphasizing the recent findings that acutely activated enhancers assemble regulatory machinery as mesoscale architectural structures with distinct physical properties. These findings help formulate novel models that explain several mysterious features of the assembly of transcriptional enhancers and the mechanisms of spatial control of gene expression.


Assuntos
DNA Viral , Elementos Facilitadores Genéticos , Sequência de Bases , Núcleo Celular/genética , Regulação da Expressão Gênica/genética
9.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36617187

RESUMO

Differential abundance analysis (DAA) is one central statistical task in microbiome data analysis. A robust and powerful DAA tool can help identify highly confident microbial candidates for further biological validation. Current microbiome studies frequently generate correlated samples from different microbiome sampling schemes such as spatial and temporal sampling. In the past decade, a number of DAA tools for correlated microbiome data (DAA-c) have been proposed. Disturbingly, different DAA-c tools could sometimes produce quite discordant results. To recommend the best practice to the field, we performed the first comprehensive evaluation of existing DAA-c tools using real data-based simulations. Overall, the linear model-based methods LinDA, MaAsLin2 and LDM are more robust than methods based on generalized linear models. The LinDA method is the only method that maintains reasonable performance in the presence of strong compositional effects.


Assuntos
Benchmarking , Microbiota , Microbiota/genética , Modelos Lineares , Bases de Dados Factuais , Metagenômica/métodos
10.
Bioinformatics ; 40(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244568

RESUMO

MOTIVATION: Emerging omics technologies have introduced a two-way grouping structure in multiple testing, as seen in single-cell omics data, where the features can be grouped by either genes or cell types. Traditional multiple testing methods have limited ability to exploit such two-way grouping structure, leading to potential power loss. RESULTS: We propose a new 2D Group Benjamini-Hochberg (2dGBH) procedure to harness the two-way grouping structure in omics data, extending the traditional one-way adaptive GBH procedure. Using both simulated and real datasets, we show that 2dGBH effectively controls the false discovery rate across biologically relevant settings, and it is more powerful than the BH or q-value procedure and more robust than the one-way adaptive GBH procedure. AVAILABILITY AND IMPLEMENTATION: 2dGBH is available as an R package at: https://github.com/chloelulu/tdGBH. The analysis code and data are available at: https://github.com/chloelulu/tdGBH-paper.


Assuntos
Genoma , Genômica , Projetos de Pesquisa
11.
PLoS Pathog ; 19(5): e1011374, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37146060

RESUMO

Aedes albopictus shows a rapid global expansion and dramatic vectorial capacity for various arboviruses, thus posing a severe threat to global health. Although many noncoding RNAs have been confirmed to play functional roles in various biological processes in Ae. albopictus, the roles of circRNA remain a mystery. In the present study, we first performed high-throughput circRNA sequencing in Ae. albopictus. Then, we identified a cysteine desulfurase (CsdA) superfamily gene-originated circRNA, named aal-circRNA-407, which was the third most abundant circRNA in adult females and displayed a fat body highly expressed manifestation and blood feeding-dependent onset. SiRNA-mediated knockdown of circRNA-407 resulted in a decrease in the number of developing follicles and a reduction in follicle size post blood meal. Furthermore, we demonstrated that circRNA-407 can act as a sponge of aal-miR-9a-5p to promote the expression of its target gene Foxl and eventually regulate ovarian development. Our study is the first to report a functional circRNA in mosquitoes, expanding our current understanding of important biological roles in mosquitoes and providing an alternative genetic strategy for mosquito control.


Assuntos
Aedes , Arbovírus , MicroRNAs , Animais , Feminino , Arbovírus/genética , Aedes/genética , RNA Circular/genética , Mosquitos Vetores/genética , MicroRNAs/genética
12.
PLoS Pathog ; 19(11): e1011754, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38032898

RESUMO

Dermal fibroblasts (dFBs) defend against deep bacterial skin infections by differentiating into preadipocytes (pAds) that produce the antimicrobial peptide cathelicidin; this differentiation is known as the dermal reactive adipogenesis response. However, the role of dFBs in fungal infection remains unknown. Here, we found that cathelicidin-producing pAds were present in high numbers in skin lesions from patients with cutaneous Candida granulomas. Second, we showed that dermal Candida albicans (C. albicans) infection in mice robustly triggered the dermal reactive adipogenesis response and induced cathelicidin expression, and inhibition of adipogenesis with pharmacological inhibitors of peroxisome proliferator-activated receptor γ (PPARγ) impaired skin resistance to C. albicans. In vitro, C. albicans products induced cathelicidin expression in pAds, and differentiating pAds markedly suppressed the growth of C. albicans by producing cathelicidin. Finally, we showed that C. albicans induced an antimicrobial response in pAds through the FGFR-MEK-ERK pathway. Together, our data reveal a previously unknown role of dFBs in the defense against skin infection caused by C. albicans.


Assuntos
Candida albicans , Candidíase , Humanos , Camundongos , Animais , Candida albicans/metabolismo , Catelicidinas , Sistema de Sinalização das MAP Quinases , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos
13.
Plant Physiol ; 195(2): 1586-1600, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38478430

RESUMO

Leaf angle is a major trait of ideal architecture, which is considered to influence rice (Oryza sativa) cultivation and grain yield. Although a few mutants with altered rice leaf inclination angles have been reported, the underlying molecular mechanism remains unclear. In this study, we showed that a WRKY transcription factor gene, OsWRKY72, was highly expressed in the leaf sheath and lamina joint. Phenotypic analyses showed that oswrky72 mutants had smaller leaf angles than the wild type, while OsWRKY72 overexpression lines exhibited an increased leaf angle. This observation suggests that OsWRKY72 functions as a positive regulator, promoting the enlargement of the leaf angle. Our bioinformatics analysis identified LAZY1 as the downstream gene of OsWRKY72. Electrophoretic mobility shift assays and dual-luciferase analysis revealed that OsWRKY72 directly inhibited LAZY1 by binding to its promoter. Moreover, knocking out OsWRKY72 enhanced shoot gravitropism, which contrasted with the phenotype of lazy1 plants. These results imply that OsWRKY72 regulates the leaf angle through gravitropism by reducing the expression of LAZY1. In addition, OsWRKY72 could directly regulate the expression of other leaf angle-related genes such as FLOWERING LOCUS T-LIKE 12 (OsFTL12) and WALL-ASSOCIATED KINASE 11 (OsWAK11). Our study indicates that OsWRKY72 contributes positively to the expansion of the leaf angle by interfering with shoot gravitropism in rice.


Assuntos
Regulação da Expressão Gênica de Plantas , Gravitropismo , Oryza , Folhas de Planta , Proteínas de Plantas , Brotos de Planta , Fatores de Transcrição , Oryza/genética , Oryza/fisiologia , Oryza/crescimento & desenvolvimento , Gravitropismo/genética , Gravitropismo/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Regiões Promotoras Genéticas/genética , Fenótipo
14.
Exp Cell Res ; : 114187, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39069152

RESUMO

BACKGROUND: Inflammation in the myocardium plays a critical role in cardiac remodeling and the pathophysiology of heart failure (HF). Previous studies have shown that mitochondrial DNA (mtDNA) can exist in different topological forms. However, the specific influence of the ratio of supercoiled/relaxed mtDNA on the inflammatory response in cardiomyocytes remains poorly understood. The aim of this study was to elucidate the differential effects of different mtDNA types on cardiomyocyte inflammation through regulation of ZBP1. MATERIALS AND METHODS: A mouse model of HF was established by transverse aortic constriction (TAC) or doxorubicin (Doxo) induction. Histopathological changes were assessed by HE staining. ELISA was used to measure cytokine levels (IL-1ß and IL-6). Southern blot analysis was performed to examine the different topology of mtDNA. Pearson correlation analysis was used to determine the correlation between the ratio of supercoiled/relaxed mtDNA and inflammatory cytokines. Reverse transcription quantitative PCR (RT-qPCR) was used to measure the mRNA expression levels of cytokines (IL-1ß, IL-6) and Dloop, as an mtDNA marker. RESULTS: The ratio of supercoiled to relaxed mtDNA was significantly increased in the myocardium of Doxo-induced mice, whereas no significant changes were observed in TAC-induced mice. The levels of IL-1ß and IL-6 were positively correlated with the cytoplasmic mtDNA supercoiled/relaxed circle ratio. Different mtDNA topology has different effects on inflammatory pathways. Low supercoiled mtDNA primarily activates the NF-κB (Ser536) pathway via ZBP1, whereas high supercoiled mtDNA significantly affects the STAT1 and STAT2 pathways. The RIPK3-NF-κB pathway, as a downstream target of ZBP1, mediates the inflammatory response induced by low supercoiled mtDNA. Knockdown of TLR9 enhances the expression of ZBP1, p-NF-κB, and RIPK3 in cardiomyocytes treated with low supercoiled mtDNA, indicating the involvement of TLR9 in the anti-inflammatory role of ZBP1 in low supercoiled mtDNA-induced inflammation. CONCLUSION: Different ratios of supercoiled to relaxed mtDNA influence the inflammatory response of cardiomyocytes and contribute to HF through the involvement of ZBP1. ZBP1, together with its downstream inflammatory mechanisms, mediates the inflammatory response induced by a low ratio of supercoiled mtDNA.

15.
Drug Resist Updat ; 74: 101078, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503142

RESUMO

AIMS: Human epidermal growth factor receptor 2 (HER2) is an oncogenic receptor tyrosine kinase amplified in approximately 20% of breast cancer (BC). HER2-targeted therapies are the linchpin of treating HER2-positive BC. However, drug resistance is common, and the main resistance mechanism is unknown. We tested the hypothesis that drug resistance results mainly from inadequate or lack of inhibition of HER2 and its family member epidermal growth factor receptor (EGFR). METHODS: We used clinically relevant cell and tumor models to assess the impact of targeted degradation of HER2 and EGFR on trastuzumab resistance. Trastuzumab is the most common clinically used HER2 inhibitor. Targeted degradation of HER2 and EGFR was achieved using recombinant human protein PEPDG278D, which binds to the extracellular domains of the receptors. siRNA knockdown was used to assess the relative importance of EGFR and HER2 in trastuzumab resistance. RESULTS: Both HER2 and EGFR are overexpressed in all trastuzumab-resistant HER2-positive BC cell and tumor models and that all trastuzumab-resistant models are highly vulnerable to targeted degradation of HER2 and EGFR. Degradation of HER2 and EGFR induced by PEPDG278D causes extensive inhibition of oncogenic signaling in trastuzumab-resistant HER2-positive BC cells. This is accompanied by strong growth inhibition of cultured cells, orthotopic patient-derived xenografts, and metastatic lesions in the brain and lung of trastuzumab-resistant HER2-positive BC. siRNA knockdown indicates that eliminating both HER2 and EGFR is necessary to maximize therapeutic outcome. CONCLUSIONS: This study unravels the therapeutic vulnerability of trastuzumab-resistant HER2-positive BC and shows that an agent that targets the degradation of both HER2 and EGFR is highly effective in overcoming drug resistance in this disease. The findings provide new insights and innovations for advancing treatment of drug-resistant HER2-positive breast cancer that remains an unmet problem.


Assuntos
Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Receptor ErbB-2 , Transdução de Sinais , Trastuzumab , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Animais , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Proteólise/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
16.
PLoS Genet ; 18(8): e1010323, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35972957

RESUMO

A growing body of theoretical and experimental evidence suggests that intramolecular epistasis is a major determinant of rates and patterns of protein evolution and imposes a substantial constraint on the evolution of novel protein functions. Here, we examine the role of intramolecular epistasis in the recurrent evolution of resistance to cardiotonic steroids (CTS) across tetrapods, which occurs via specific amino acid substitutions to the α-subunit family of Na,K-ATPases (ATP1A). After identifying a series of recurrent substitutions at two key sites of ATP1A that are predicted to confer CTS resistance in diverse tetrapods, we then performed protein engineering experiments to test the functional consequences of introducing these substitutions onto divergent species backgrounds. In line with previous results, we find that substitutions at these sites can have substantial background-dependent effects on CTS resistance. Globally, however, these substitutions also have pleiotropic effects that are consistent with additive rather than background-dependent effects. Moreover, the magnitude of a substitution's effect on activity does not depend on the overall extent of ATP1A sequence divergence between species. Our results suggest that epistatic constraints on the evolution of CTS-resistant forms of Na,K-ATPase likely depend on a small number of sites, with little dependence on overall levels of protein divergence. We propose that dependence on a limited number sites may account for the observation of convergent CTS resistance substitutions observed among taxa with highly divergent Na,K-ATPases (See S1 Text for Spanish translation).


Assuntos
ATPase Trocadora de Sódio-Potássio , Toxinas Biológicas , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/genética
17.
Nano Lett ; 24(30): 9311-9321, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39023921

RESUMO

The doping of perovskites with mixed cations and mixed halides is an effective strategy to optimize phase stability. In this study, we introduce a cubic black phase perovskite CsyFA(1-y)Pb(BrxI(1-x))3 artificial synapse, using phase engineering by adjusting the cesium-bromide content. Low-bromine mixed perovskites are suitable to improve the electric pulse excitation sensitivity and stability of the device. Specifically, the low-bromine and low-cesium mixed perovskite (x = 0.15, y = 0.22) annealed at 373 K allows the device to maintain logic response even after 1000 mechanical flex/flat cycles. The device also shows good thermal stability up to temperatures of 333 K. We have demonstrated reflex-arc behavior with MCMHP synaptic units, capable of making sensory warnings at high frequency. This compositionally engineered, dual-mixed perovskite synaptic device provides significant potential for perceptual soft neurorobotic systems and prostheses.

18.
Nano Lett ; 24(15): 4336-4345, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567915

RESUMO

This study demonstrates the conceptual design and fabrication of a vertically integrated monolithic (VIM) neuromorphic device. The device comprises an n-type SnO2 nanowire bottom channel connected by a shared gate to a p-type P3HT nanowire top channel. This architecture establishes two distinct neural pathways with different response behaviors. The device generates excitatory and inhibitory postsynaptic currents, mimicking the corelease mechanism of bilingual synapses. To enhance the signal processing efficiency, we employed a bipolar spike encoding strategy to convert fluctuating sensory signals to spike trains containing positive and negative pulses. Utilizing the neuromorphic platform for synaptic processing, physiological signals featuring bidirectional fluctuations, including electrocardiogram and breathing signals, can be classified with an accuracy of over 90%. The VIM device holds considerable promise as a solution for developing highly integrated neuromorphic hardware for healthcare and edge intelligence applications.


Assuntos
Nanofios , Sinapses
19.
J Cell Mol Med ; 28(10): e18317, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38801409

RESUMO

Euphorbiae Humifusae Herba (EHH) is a pivotal therapeutic agent with diverse pharmacological effects. However, a substantial gap exists in understanding its pharmacological properties and anti-tumour mechanisms. This study aimed to address this gap by exploring EHH's pharmacological properties, identifying NSCLC therapy-associated protein targets, and elucidating how EHH induces mitochondrial disruption in NSCLC cells, offering insights into novel NSCLC treatment strategies. String database was utilized to explore protein-protein interactions. Subsequently, single-cell analysis and multi-omics further unveiled the impact of EHH-targeted genes on the immune microenvironment of NSCLC, as well as their influence on immunotherapeutic responses. Finally, both in vivo and in vitro experiments elucidated the anti-tumour mechanisms of EHH, specifically through the assessment of mitochondrial ROS levels and alterations in mitochondrial membrane potential. EHH exerts its influence through engagement with a cluster of 10 genes, including the apoptotic gene CASP3. This regulatory impact on the immune milieu within NSCLC holds promise as an indicator for predicting responses to immunotherapy. Besides, EHH demonstrated the capability to induce mitochondrial ROS generation and perturbations in mitochondrial membrane potential in NSCLC cells, ultimately leading to mitochondrial dysfunction and consequent apoptosis of tumour cells. EHH induces mitochondrial disruption in NSCLC cells, leading to cell apoptosis to inhibit the progress of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Mitocôndrias , Análise de Célula Única , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Camundongos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral , Apoptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Medicamentos de Ervas Chinesas/farmacologia , Multiômica
20.
Ecol Lett ; 27(1): e14330, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866881

RESUMO

The associations of arbuscular mycorrhizal (AM) or ectomycorrhiza (EcM) fungi with plants have sequentially evolved and significantly contributed to enhancing plant nutrition. Nonetheless, how evolutionary and ecological forces drive nutrient acquisition strategies of AM and EcM woody plants remains poorly understood. Our global analysis of woody species revealed that, over divergence time, AM woody plants evolved faster nitrogen mineralization rates without changes in nitrogen resorption. However, EcM woody plants exhibited an increase in nitrogen mineralization but a decrease in nitrogen resorption, indicating a shift towards a more inorganic nutrient economy. Despite this alteration, when evaluating present-day woody species, AM woody plants still display faster nitrogen mineralization and lower nitrogen resorption than EcM woody plants. This inorganic nutrient economy allows AM woody plants to thrive in warm environments with a faster litter decomposition rate. Our findings indicate that the global pattern of nutrient acquisition strategies in mycorrhizal plants is shaped by the interplay between phylogeny and climate.


Assuntos
Micorrizas , Raízes de Plantas/microbiologia , Nitrogênio , Plantas , Nutrientes , Solo , Simbiose
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