RESUMO
Histone H3.3 is frequently mutated in tumors, with the lysine 36 to methionine mutation (K36M) being a hallmark of chondroblastomas. While it is known that H3.3K36M changes the epigenetic landscape, its effects on gene expression dynamics remain unclear. Here, we use a synthetic reporter to measure the effects of H3.3K36M on silencing and epigenetic memory after recruitment of the ZNF10 Krüppel-associated box (KRAB) domain, part of the largest class of human repressors and associated with H3K9me3 deposition. We find that H3.3K36M, which decreases H3K36 methylation and increases histone acetylation, leads to a decrease in epigenetic memory and promoter methylation weeks after KRAB release. We propose a model for establishment and maintenance of epigenetic memory, where the H3K36 methylation pathway is necessary to maintain histone deacetylation and convert H3K9me3 domains into DNA methylation for stable epigenetic memory. Our quantitative model can inform oncogenic mechanisms and guide development of epigenetic editing tools.
Assuntos
Metilação de DNA , Epigênese Genética , Histonas , Mutação , Histonas/metabolismo , Histonas/genética , Humanos , Acetilação , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Lisina/metabolismo , Memória EpigenéticaRESUMO
Hepatocellular carcinoma (HCC) often develops following chronic hepatitis B virus (HBV) infection and responds poorly to immune checkpoint blockade. Here, we examined the antigen specificities of HCC-infiltrating T cells and their relevance to tumor control. Using highly multiplexed peptide-MHC tetramer staining of unexpanded cells from blood, liver, and tumor tissues from 46 HCC patients, we detected 91 different antigen-specific CD8+ T cell populations targeting HBV, neoantigen, tumor-associated, and disease-unrelated antigens. Parallel high-dimensional analysis delineated five distinct antigen-specific tissue-resident memory T (Trm) cell populations. Intratumoral and intrahepatic HBV-specific T cells were enriched for two Trm cell subsets that were PD-1loTOXlo, despite being clonally expanded. High frequencies of intratumoral terminally exhausted T cells were uncommon. Patients with tumor-infiltrating HBV-specific CD8+ Trm cells exhibited longer-term relapse-free survival. Thus, non-terminally exhausted HBV-specific CD8+ Trm cells show hallmarks of active involvement and effective antitumor response, implying that these cells could be harnessed for therapeutic purposes.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/imunologia , Memória Imunológica/imunologia , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Antígenos de Neoplasias/imunologia , Carcinoma Hepatocelular/patologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/prevenção & controle , Receptor de Morte Celular Programada 1/metabolismo , Células Tumorais CultivadasRESUMO
The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna1. These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history2,3. Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri.
Assuntos
Adansonia , Filogenia , Adansonia/classificação , Adansonia/genética , Biodiversidade , Conservação dos Recursos Naturais , Ecologia , Espécies em Perigo de Extinção , Evolução Molecular , Genoma de Planta/genética , Madagáscar , Dinâmica Populacional , Elevação do Nível do MarRESUMO
Mitotic Arrest Deficient 1 (gene name MAD1L1), an essential component of the mitotic spindle assembly checkpoint, is frequently overexpressed in colon cancer, which correlates with poor disease-free survival. MAD1 upregulation induces two phenotypes associated with tumor promotion in tissue culture cells-low rates of chromosomal instability (CIN) and destabilization of the tumor suppressor p53. Using CRISPR/Cas9 gene editing, we generated a novel mouse model by inserting a doxycycline (dox)-inducible promoter and HA tag into the endogenous mouse Mad1l1 gene, enabling inducible expression of HA-MAD1 following exposure to dox in the presence of the reverse tet transactivator (rtTA). A modest 2-fold overexpression of MAD1 in murine colon resulted in decreased p53 expression and increased mitotic defects consistent with CIN. After exposure to the colon-specific inflammatory agent dextran sulfate sodium (DSS), 31% of mice developed colon lesions, including a mucinous adenocarcinoma, while none formed in control animals. Lesion incidence was particularly high in male mice, 57% of which developed at least one hyperplastic polyp, adenoma or adenocarcinoma in the colon. Notably, mice expressing HA-MAD1 also developed lesions in tissues in which DSS is not expected to induce inflammation. These findings demonstrate that MAD1 upregulation is sufficient to promote colon tumorigenesis in the context of inflammation in immune-competent mice.
Assuntos
Proteínas de Ciclo Celular , Neoplasias do Colo , Inflamação , Animais , Feminino , Humanos , Masculino , Camundongos , Carcinogênese , Proteínas de Ciclo Celular/metabolismo , Instabilidade Cromossômica , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Sistemas CRISPR-Cas , Sulfato de Dextrana , Regulação Neoplásica da Expressão Gênica , Inflamação/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para CimaRESUMO
Insects represent the most diverse animal group, yet previous phylogenetic analyses based on morphological and molecular data have failed to agree on the evolutionary relationships of early insects and their six-legged relatives (together constituting the clade Hexapoda). In particular, the phylogenetic positions of the three early-diverging hexapod lineages-the coneheads (Protura), springtails (Collembola), and two-pronged bristletails (Diplura)-have been debated for over a century, with alternative topologies implying drastically different scenarios of the evolution of the insect body plan and hexapod terrestrialization. We addressed this issue by sampling all hexapod orders and experimenting with a broad range of across-site compositional heterogeneous models designed to tackle ancient divergences. Our analyses support Protura as the earliest-diverging hexapod lineage ("Protura-sister") and Collembola as a sister group to Diplura, a clade corresponding to the original composition of Entognatha, and characterized by the shared possession of internal muscles in the antennal flagellum. The previously recognized 'Elliplura' hypothesis is recovered only under the site-homogeneous substitution models with partial supermatrices. Our cross-validation analysis shows that the site-heterogeneous CAT-GTR model, which recovers "Protura-sister," fits significantly better than homogeneous models. Furthermore, the morphologically unusual Protura are also supported as the earliest-diverging hexapod lineage by other lines of evidence, such as mitogenomes, comparative embryology, and sperm morphology, which produced results similar to those in this study. Our backbone phylogeny of hexapods will facilitate the exploration of the underpinnings of hexapod terrestrialization and megadiversity.
Assuntos
Insetos , Filogenia , Animais , Insetos/classificação , Insetos/genética , Insetos/anatomia & histologia , Evolução Biológica , Artrópodes/classificação , Artrópodes/genética , Artrópodes/anatomia & histologiaRESUMO
In recent years, the advent of spatial transcriptomics (ST) technology has unlocked unprecedented opportunities for delving into the complexities of gene expression patterns within intricate biological systems. Despite its transformative potential, the prohibitive cost of ST technology remains a significant barrier to its widespread adoption in large-scale studies. An alternative, more cost-effective strategy involves employing artificial intelligence to predict gene expression levels using readily accessible whole-slide images stained with Hematoxylin and Eosin (H&E). However, existing methods have yet to fully capitalize on multimodal information provided by H&E images and ST data with spatial location. In this paper, we propose mclSTExp, a multimodal contrastive learning with Transformer and Densenet-121 encoder for Spatial Transcriptomics Expression prediction. We conceptualize each spot as a "word", integrating its intrinsic features with spatial context through the self-attention mechanism of a Transformer encoder. This integration is further enriched by incorporating image features via contrastive learning, thereby enhancing the predictive capability of our model. We conducted an extensive evaluation of highly variable genes in two breast cancer datasets and a skin squamous cell carcinoma dataset, and the results demonstrate that mclSTExp exhibits superior performance in predicting spatial gene expression. Moreover, mclSTExp has shown promise in interpreting cancer-specific overexpressed genes, elucidating immune-related genes, and identifying specialized spatial domains annotated by pathologists. Our source code is available at https://github.com/shizhiceng/mclSTExp.
Assuntos
Perfilação da Expressão Gênica , Humanos , Perfilação da Expressão Gênica/métodos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Biologia Computacional/métodos , Transcriptoma , Feminino , Aprendizado de Máquina , Regulação Neoplásica da Expressão GênicaRESUMO
Prostate cancer (PCa) is the most prevalent cancer affecting American men. Castration-resistant prostate cancer (CRPC) can emerge during hormone therapy for PCa, manifesting with elevated serum prostate-specific antigen levels, continued disease progression, and/or metastasis to the new sites, resulting in a poor prognosis. A subset of CRPC patients shows a neuroendocrine (NE) phenotype, signifying reduced or no reliance on androgen receptor signaling and a particularly unfavorable prognosis. In this study, we incorporated computational approaches based on both gene expression profiles and protein-protein interaction networks. We identified 500 potential marker genes, which are significantly enriched in cell cycle and neuronal processes. The top 40 candidates, collectively named CDHu40, demonstrated superior performance in distinguishing NE PCa (NEPC) and non-NEPC samples based on gene expression profiles. CDHu40 outperformed most of the other published marker sets, excelling particularly at the prognostic level. Notably, some marker genes in CDHu40, absent in the other marker sets, have been reported to be associated with NEPC in the literature, such as DDC, FOLH1, BEX1, MAST1, and CACNA1A. Importantly, elevated CDHu40 scores derived from our predictive model showed a robust correlation with unfavorable survival outcomes in patients, indicating the potential of the CDHu40 score as a promising indicator for predicting the survival prognosis of those patients with the NE phenotype. Motif enrichment analysis on the top candidates suggests that REST and E2F6 may serve as key regulators in the NEPC progression.
Assuntos
Biomarcadores Tumorais , Humanos , Masculino , Biomarcadores Tumorais/genética , Prognóstico , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Mapas de Interação de Proteínas , Perfilação da Expressão Gênica , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Biologia Computacional/métodos , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/metabolismoRESUMO
Chromosome segregation during mitosis is highly regulated to ensure production of genetically identical progeny. Recurrent mitotic errors cause chromosomal instability (CIN), a hallmark of tumors. The E6 and E7 oncoproteins of high-risk human papillomavirus (HPV), which causes cervical, anal, and head and neck cancers (HNC), cause mitotic defects consistent with CIN in models of anogenital cancers, but this has not been studied in the context of HNC. Here, we show that HPV16 induces a specific type of CIN in patient HNC tumors, patient-derived xenografts, and cell lines, which is due to defects in chromosome congression. These defects are specifically induced by the HPV16 oncogene E6 rather than E7. We show that HPV16 E6 expression causes degradation of the mitotic kinesin CENP-E, whose depletion produces chromosomes that are chronically misaligned near spindle poles (polar chromosomes) and fail to congress. Though the canonical oncogenic role of E6 is the degradation of the tumor suppressor p53, CENP-E degradation and polar chromosomes occur independently of p53. Instead, E6 directs CENP-E degradation in a proteasome-dependent manner via the E6-associated ubiquitin protein ligase E6AP/UBE3A. This study reveals a mechanism by which HPV induces CIN, which may impact HPV-mediated tumor initiation, progression, and therapeutic response.
Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Instabilidade Cromossômica , Cromossomos/metabolismo , Papillomavirus Humano 16/genética , Cinesinas/genética , Cinesinas/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Significant knowledge gaps exist regarding the responses of cells, tissues, and organs to organismal death. Examining the survival mechanisms influenced by metabolism and environment, this research has the potential to transform regenerative medicine, redefine legal death, and provide insights into life's physiological limits, paralleling inquiries in embryogenesis.
Assuntos
Morte , Humanos , AnimaisRESUMO
C1 inhibitor (C1INH) is a multifunctional serine protease inhibitor that functions as a major negative regulator of several biological pathways, including the contact pathway of blood coagulation. In humans, congenital C1INH deficiency results in a rare episodic bradykinin-mediated swelling disorder called hereditary angioedema (HAE). Patients with C1INH deficiency-associated HAE (C1INH-HAE) have increased circulating markers of activation of coagulation. Furthermore, we recently reported that patients with C1INH-HAE had a moderate but significant increased risk of venous thromboembolism. To further investigate the impact of C1INH deficiency on activation of coagulation and thrombosis, we conducted studies using patient samples and mouse models. Plasmas from patients with C1INH-HAE had significantly increased contact pathway-mediated thrombin generation. C1INH-deficient mice, which have been used as a model of C1INH-HAE, had significantly increased baseline circulating levels of prothrombin fragment 1+2 and thrombin-antithrombin complexes. In addition, whole blood from C1INH-deficient mice supported significantly increased contact pathway-mediated thrombin generation. Importantly, C1INH-deficient mice exhibited significantly enhanced venous, but not arterial, thrombus formation. Furthermore, purified human C1INH normalized contact pathway-mediated thrombin generation and venous thrombosis in C1INH-deficient mice. These findings highlight a key role for endogenous C1INH as a negative regulator of contact pathway-mediated coagulation in humans and mice. Further, this work identifies endogenous C1INH as an important negative regulator of venous thrombus formation in mice, complementing the phenotype associated with C1INH-HAE.
Assuntos
Angioedemas Hereditários , Trombose , Trombose Venosa , Humanos , Animais , Camundongos , Angioedemas Hereditários/genética , Trombina , Proteína Inibidora do Complemento C1/genética , Coagulação Sanguínea , Trombose/etiologia , Trombose Venosa/etiologiaRESUMO
Acute myeloid leukemia (AML) is an aggressive blood cancer with poor prognosis. FMS-like tyrosine kinase receptor-3 (FLT3) is one of the major oncogenic receptor tyrosine kinases aberrantly activated in AML. Although protein tyrosine phosphatase PRL2 is highly expressed in some subtypes of AML compared with normal human hematopoietic stem and progenitor cells, the mechanisms by which PRL2 promotes leukemogenesis are largely unknown. We discovered that genetic and pharmacological inhibition of PRL2 significantly reduce the burden of FLT3-internal tandem duplications-driven leukemia and extend the survival of leukemic mice. Furthermore, we found that PRL2 enhances oncogenic FLT3 signaling in leukemia cells, promoting their proliferation and survival. Mechanistically, PRL2 dephosphorylates the E3 ubiquitin ligase CBL at tyrosine 371 and attenuates CBL-mediated ubiquitination and degradation of FLT3, leading to enhanced FLT3 signaling in leukemia cells. Thus, our study reveals that PRL2 enhances oncogenic FLT3 signaling in leukemia cells through dephosphorylation of CBL and will likely establish PRL2 as a novel druggable target for AML.
Assuntos
Leucemia Mieloide Aguda , Ubiquitina-Proteína Ligases , Humanos , Animais , Camundongos , Ubiquitina-Proteína Ligases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Transdução de Sinais/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas Proto-Oncogênicas c-cbl/genética , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , MutaçãoRESUMO
Targeting cardiac remodeling is regarded as a key therapeutic strategy for heart failure. Kielin/chordin-like protein (KCP) is a secretory protein with 18 cysteine-rich domains and associated with kidney and liver fibrosis. However, the relationship between KCP and cardiac remodeling remains unclear. Here, we aimed to investigate the role of KCP in cardiac remodeling induced by pressure overload and explore its potential mechanisms. Left ventricular (LV) KCP expression was measured with real-time quantitative PCR, western blotting, and immunofluorescence staining in pressure overload-induced cardiac remodeling in mice. Cardiac function and remodeling were evaluated in wide-type (WT) mice and KCP knockout (KO) mice by echocardiography, which were further confirmed by histological analysis with hematoxylin and eosin and Masson staining. RNA sequence was performed with LV tissue from WT and KO mice to identify differentially expressed genes and related signaling pathways. Primary cardiac fibroblasts (CFs) were used to validate the regulatory role and potential mechanisms of KCP during fibrosis. KCP was down-regulated in the progression of cardiac remodeling induced by pressure overload, and was mainly expressed in fibroblasts. KCP deficiency significantly aggravated pressure overload-induced cardiac dysfunction and remodeling. RNA sequence revealed that the role of KCP deficiency in cardiac remodeling was associated with cell division, cell cycle, and P53 signaling pathway, while cyclin B1 (CCNB1) was the most significantly up-regulated gene. Further investigation in vivo and in vitro suggested that KCP deficiency promoted the proliferation of CFs via P53/P21/CCNB1 pathway. Taken together, these results suggested that KCP deficiency aggravates cardiac dysfunction and remodeling induced by pressure overload via P53/P21/CCNB1 signaling in mice.
Assuntos
Glicoproteínas , Insuficiência Cardíaca , Peptídeos e Proteínas de Sinalização Intercelular , Deficiência de Proteína , Animais , Camundongos , Proteína Supressora de Tumor p53/genética , Ciclina B1 , Remodelação Ventricular , Transdução de SinaisRESUMO
Taxane-induced peripheral neuropathy (TIPN) is a devastating survivorship issue for many cancer patients. In addition to its impact on quality of life, this toxicity may lead to dose reductions or treatment discontinuation, adversely impacting survival outcomes and leading to health disparities in African Americans (AA). Our lab has previously identified deleterious mutations in SET-Binding Factor 2 (SBF2) that significantly associated with severe TIPN in AA patients. Here, we demonstrate the impact of SBF2 on taxane-induced neuronal damage using an ex vivo model of SBF2 knockdown of induced pluripotent stem cell-derived sensory neurons. Knockdown of SBF2 exacerbated paclitaxel changes to cell viability and neurite outgrowth while attenuating paclitaxel-induced sodium current inhibition. Our studies identified paclitaxel-induced expression changes specific to mature sensory neurons and revealed candidate genes involved in the exacerbation of paclitaxel-induced phenotypes accompanying SBF2 knockdown. Overall, these findings provide ex vivo support for the impact of SBF2 on the development of TIPN and shed light on the potential pathways involved.
Assuntos
Paclitaxel/efeitos adversos , Doenças do Sistema Nervoso Periférico/genética , Polimorfismo de Nucleotídeo Único , Proteínas Tirosina Fosfatases não Receptoras/genética , Células Receptoras Sensoriais/citologia , Negro ou Afro-Americano/genética , Sobrevivência Celular/efeitos dos fármacos , Progressão da Doença , Feminino , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/química , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Paclitaxel/farmacologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/etnologia , Qualidade de Vida , Células Receptoras Sensoriais/química , Células Receptoras Sensoriais/efeitos dos fármacos , Análise de Sequência de RNA , Análise de Célula Única , População Branca/genéticaRESUMO
Accumulating evidence has revealed that chronic unresolved inflammation can cause significant tissue damage and can be a key mediator of advanced heart failure (HF). Resolvin (Rv) D2, a member of specialized pro-resolving lipid mediators (SPMs), plays a protective role in various diseases by facilitating resolution. However, whether RvD2 participates in the pathogenesis of HF is still unclear. Our study demonstrated that RvD2 treatment mitigated cardiac remodeling and improved cardiac function in HF mice induced by pressure overload. The absence of G protein-coupled receptor 18 (GPR18), an endogenous receptor for RvD2, abolished the beneficial effects of RvD2 on HF. Additionally, RvD2 inhibited inflammatory responses and Ly6Chigh macrophage polarization during both early and late inflammatory stages involved in HF. Further investigation revealed that bone marrow transplantation from GPR18 deficient mice into WT mice blocked the protective effects of RvD2 in HF mice. Moreover, GPR18 deficiency impeded RvD2's capacity to downregulate inflammatory responses and Ly6Chigh macrophage polarization. Consistent with experiments in vivo, RvD2 treatment in bone marrow-derived macrophages (BMDMs) reduced inflammatory responses through its receptor GPR18. Mechanistically, RvD2 suppressed the phosphorylation of STAT1 and NF-κB p65, and the effects of RvD2 were reversed by the application of STAT1 or NF-κB p65 agonists in BMDMs. In conclusion, RvD2/GPR18 axis improved cardiac remodeling and function in pressure overload-induced HF mice by modulating macrophages phenotype via STAT1 and NF-κB p65 pathways. Our findings underscore the anti-inflammatory potential of RvD2/GPR18 axis, which may be a promising strategy for reducing the burden of HF.
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BACKGROUND: Mesenchymal stem cells (MSCs) are multipotent stem cells that are under investigation for use in clinical trials because they are capable of self-renewal and differentiating into different cell types under defined conditions. Nonetheless, the therapeutic effects of MSCs have been constrained by low engraftment rates, cell fusion, and cell survival. Various strategies have been explored to improve the therapeutic efficacy of MSCs, with platelet-derived growth factor (PDGF)-BB emerging as a promising candidate. To enhance our comprehension of the impact of PDGF-BB on the gene expression profile and chromosomal accessibility of MSCs, RNA-sequencing and analysis of chromatin accessibility profiles were conducted on three human primary MSCs in culture, both with and without stimulation by PDGF-BB. RESULTS: Integrative analysis of gene expression and chromatin accessibility demonstrated that PDGF-BB treatment modified the chromatin accessibility landscape, marking regions for activation or repression through the AP-1 family transcription factors TEAD, CEBP, and RUNX2. These changes in AP-1 transcription factor expression, in turn, led to cell proliferation and differentiation potential towards osteoblasts, adipocytes, or chondrocytes. The degree of MSC differentiation varies among cells isolated from different donors. The presence of an enrichment of exosome-related genes is also noted among all the differentially expressed genes. CONCLUSIONS: In conclusion, the observed changes in AP-1 transcription factor expression not only induced cellular proliferation and differentiation, but also revealed variations in the degree of MSC differentiation based on donor-specific differences. Moreover, the enrichment of exosome-related genes among differentially expressed genes suggests a potential significant role for PDGF-BB in facilitating intercellular communication.
Assuntos
Becaplermina , Diferenciação Celular , Cromatina , Células-Tronco Mesenquimais , Transcriptoma , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Humanos , Becaplermina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Cromatina/metabolismo , Cromatina/genética , Células Cultivadas , Proliferação de Células/efeitos dos fármacos , Perfilação da Expressão Gênica , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Proteínas Proto-Oncogênicas c-sis/farmacologiaRESUMO
Polycomb repressive complex 2 (PRC2) deposits H3K27me3 on chromatin to silence transcription. PRC2 broadly interacts with RNAs. Currently, the role of the RNA-PRC2 interaction in human cardiogenesis remains elusive. Here, we found that human-specific heart brake lncRNA 1 (HBL1) interacted with two PRC2 subunits, JARID2 and EED, in human pluripotent stem cells (hPSCs). Loss of JARID2, EED or HBL1 significantly enhanced cardiac differentiation from hPSCs. HBL1 depletion disrupted genome-wide PRC2 occupancy and H3K27me3 chromatin modification on essential cardiogenic genes, and broadly enhanced cardiogenic gene transcription in undifferentiated hPSCs and later-on differentiation. In addition, ChIP-seq revealed reduced EED occupancy on 62 overlapped cardiogenic genes in HBL1-/- and JARID2-/- hPSCs, indicating that the epigenetic state of cardiogenic genes was determined by HBL1 and JARID2 at pluripotency stage. Furthermore, after cardiac development occurs, the cytosolic and nuclear fractions of HBL1 could crosstalk via a conserved 'microRNA-1-JARID2' axis to modulate cardiogenic gene transcription. Overall, our findings delineate the indispensable role of HBL1 in guiding PRC2 function during early human cardiogenesis, and expand the mechanistic scope of lncRNA(s) that cytosolic and nuclear portions of HBL1 could coordinate to orchestrate human cardiogenesis.
Assuntos
Genoma , Organogênese , Células-Tronco Pluripotentes/metabolismo , Complexo Repressor Polycomb 2/genética , RNA Longo não Codificante/metabolismo , Diferenciação Celular , Cromatina , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Coração/crescimento & desenvolvimento , Histonas/genética , Humanos , MicroRNAsRESUMO
Thrombocytopenia is a critical complication after radiation therapy and exposure. Dysfunction of megakaryocyte development and platelet production are key pathophysiological stages in ionizing radiation (IR)-induced thrombocytopenia. Protein kinase C (PKC) plays an important role in regulating megakaryocyte development and platelet production. However, it remains unclear how PKC regulates IR-induced megakaryocyte apoptosis. In this study, we found that pretreatment of PKC pan-inhibitor Go6983 delayed IR-induced megakaryocyte apoptosis, and inhibited IR-induced mitochondrial membrane potential and ROS production in CMK cells. Moreover, suppressing PKC activation inhibited cleaved caspase3 expression and reduced p38 phosphorylation levels, and IR-induced PKC activation might be regulated by p53. In vivo experiments confirmed that Go6983 promoted platelet count recovery after 21 days of 3 Gy total body irradiation. Furthermore, Go6983 reduced megakaryocyte apoptosis, increased the number of megakaryocyte and polyploid formation in bone marrow, and improved the survival rate of 6 Gy total body irradiation. In conclusion, our results provided a potential therapeutic target for IR-induced thrombocytopenia.
Assuntos
Megacariócitos , Trombocitopenia , Humanos , Proteína Quinase C/metabolismo , Proteína Quinase C/uso terapêutico , Raios X , Trombocitopenia/etiologia , Trombopoese , Apoptose , PlaquetasRESUMO
The outbreak of acute respiratory disease in 2019, namely Coronavirus Disease-2019 (COVID-19), has become an unprecedented healthcare crisis. To mitigate the pandemic, there are a lot of collective and multidisciplinary efforts in facilitating the rapid discovery of protein inhibitors or drugs against COVID-19. Although many computational methods to predict protein inhibitors have been developed [ 1- 5], few systematic reviews on these methods have been published. Here, we provide a comprehensive overview of the existing methods to discover potential inhibitors of COVID-19 virus, so-called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). First, we briefly categorize and describe computational approaches by the basic algorithms involved in. Then we review the related biological datasets used in such predictions. Furthermore, we emphatically discuss current knowledge on SARS-CoV-2 inhibitors with the latest findings and development of computational methods in uncovering protein inhibitors against COVID-19.
Assuntos
Antivirais/química , Tratamento Farmacológico da COVID-19 , COVID-19 , Biologia Computacional , Simulação de Acoplamento Molecular , Pandemias , SARS-CoV-2/metabolismo , Antivirais/uso terapêutico , COVID-19/epidemiologia , Bases de Dados Factuais , HumanosRESUMO
We propose a scheme for realizing nonreciprocal microwave photon routing with two cascaded magnon-cavity coupled systems, which work around the exceptional points of a parity-time (PT)-symmetric Hamiltonian. An almost perfect nonreciprocal transmission can be achieved with a broad bandwidth, where the transmission for a forward-propagating photon can be flexibly controlled with the backpropagating photon being isolated. The transmission or isolated direction can be reversed via simply controlling the magnetic field direction applied to the magnons. The isolation bandwidth is improved by almost three times in comparison with the device based on a single PT-symmetric system. Moreover, the effect of intrinsic cavity loss and added thermal noises is considered, confirming the experimental feasibility of the nonreciprocal device and potential applications in quantum information processing.
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Transient receptor potential ankyrin 1 (TRPA1) plays an important role in different cardiovascular diseases. However, the role of TRPA1 in dilated cardiomyopathy (DCM) remains unclear. Here, we aimed to investigate the role of TRPA1 in DCM induced by doxorubicin (DOX) and explore its possible mechanisms. GEO data were used to explore the expression of TRPA1 in DCM patients. DOX (2.5 mg/kg/week, 6 weeks, i.p.) was used to induce DCM. Bone marrow-derived macrophages (BMDMs) and neonatal rat cardiomyocytes (NRCMs) were isolated to explore the role of TRPA1 in macrophage polarization, cardiomyocyte apoptosis, and pyroptosis. In addition, DCM rats were treated with the TRPA1 activator, cinnamaldehyde to explore the possibility of clinical translation. TRPA1 expression was increased in left ventricular (LV) tissue in DCM patients and rats. TRPA1 deficiency aggravated the cardiac dysfunction, cardiac injury, and LV remodeling in DCM rats. In addition, TRPA1 deficiency promoted the M1 macrophage polarization, oxidative stress, cardiac apoptosis, and pyroptosis induced by DOX. RNA-seq results showed that TRPA1 knockout promoted the expression of S100A8, an inflammatory molecule that belongs to the family of Ca2+ -binding S100 proteins, in DCM rats. Furthermore, S100A8 inhibition attenuated M1 macrophage polarization in BMDMs isolated from TRPA1 deficiency rats. Recombinant S100A8 promoted the apoptosis, pyroptosis, and oxidative stress in primary cardiomyocytes stimulated with DOX. Finally, TRPA1 activation via cinnamaldehyde alleviated the cardiac dysfunction and reduced S100A8 expression in DCM rats. Taken together, these results suggested that TRPA1 deficiency aggravates DCM by promoting S100A8 expression to induce M1 macrophage polarization and cardiac apoptosis.