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1.
J Clin Invest ; 134(10)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530357

RESUMO

Despite widespread utilization of immunotherapy, treating immune-cold tumors remains a challenge. Multiomic analyses and experimental validation identified the OTUD4/CD73 proteolytic axis as a promising target in treating immune-suppressive triple negative breast cancer (TNBC). Mechanistically, deubiquitylation of CD73 by OTUD4 counteracted its ubiquitylation by TRIM21, resulting in CD73 stabilization inhibiting tumor immune responses. We further demonstrated the importance of TGF-ß signaling for orchestrating the OTUD4/CD73 proteolytic axis within tumor cells. Spatial transcriptomics profiling discovered spatially resolved features of interacting malignant and immune cells pertaining to expression levels of OTUD4 and CD73. In addition, ST80, a newly developed inhibitor, specifically disrupted proteolytic interaction between CD73 and OTUD4, leading to reinvigoration of cytotoxic CD8+ T cell activities. In preclinical models of TNBC, ST80 treatment sensitized refractory tumors to anti-PD-L1 therapy. Collectively, our findings uncover what we believe to be a novel strategy for targeting the immunosuppressive OTUD4/CD73 proteolytic axis in treating immune-suppressive breast cancers with the inhibitor ST80.


Assuntos
5'-Nucleotidase , Proteólise , Neoplasias de Mama Triplo Negativas , Humanos , 5'-Nucleotidase/genética , 5'-Nucleotidase/imunologia , 5'-Nucleotidase/antagonistas & inibidores , Feminino , Camundongos , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Animais , Linhagem Celular Tumoral , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Ubiquitinação
2.
PLoS One ; 19(3): e0299237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446813

RESUMO

The linkages between the US and China, the world's two major agricultural powers, have brought great uncertainty to the global food markets. Inspired by these, this paper examines the extreme risk spillovers between US and Chinese agricultural futures markets during significant crises. We use a copula-conditional value at risk (CoVaR) model with Markov-switching regimes to capture the tail dependence in their pair markets. The study covers the period from January 2006 to December 2022 and identifies two distinct dependence regimes (stable and crisis periods). Moreover, we find significant and asymmetric upside/downside extreme risk spillovers between the US and Chinese markets, which are highly volatile in crises. Additionally, the impact of international capital flows (the financial channel) on risk spillovers is particularly pronounced during the global financial crisis. During the period of the COVID-19 pandemic and the Russia-Ukraine 2022 war, the impact of supply chain disruptions (the non-financial channel) is highlighted. Our findings provide a theoretical reference for monitoring the co-movements in agricultural futures markets and practical insights for managing investment portfolios and enhancing food market stability during crises.


Assuntos
COVID-19 , Agricultura , China , COVID-19/epidemiologia , Pandemias
3.
Semin Cancer Biol ; 90: 29-44, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36806560

RESUMO

Despite the development of cancer therapies, the success of most treatments has been impeded by drug resistance. The crucial role of tumor cell plasticity has emerged recently in cancer progression, cancer stemness and eventually drug resistance. Cell plasticity drives tumor cells to reversibly convert their cell identity, analogous to differentiation and dedifferentiation, to adapt to drug treatment. This phenotypical switch is driven by alteration of the transcriptome. Several pluripotent factors from the KLF and SOX families are closely associated with cancer pathogenesis and have been revealed to regulate tumor cell plasticity. In this review, we particularly summarize recent studies about KLF4, KLF5 and SOX factors in cancer development and evolution, focusing on their roles in cancer initiation, invasion, tumor hierarchy and heterogeneity, and lineage plasticity. In addition, we discuss the various regulation of these transcription factors and related cutting-edge drug development approaches that could be used to drug "undruggable" transcription factors, such as PROTAC and PPI targeting, for targeted cancer therapy. Advanced knowledge could pave the way for the development of novel drugs that target transcriptional regulation and could improve the outcome of cancer therapy.


Assuntos
Fatores de Transcrição Kruppel-Like , Neoplasias , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fator 4 Semelhante a Kruppel , Neoplasias/etiologia , Neoplasias/genética , Fatores de Transcrição , Regulação da Expressão Gênica
4.
PLoS Genet ; 17(7): e1009635, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34237064

RESUMO

The intracellular level of fatty aldehydes is tightly regulated by aldehyde dehydrogenases to minimize the formation of toxic lipid and protein adducts. Importantly, the dysregulation of aldehyde dehydrogenases has been implicated in neurologic disorder and cancer in humans. However, cellular responses to unresolved, elevated fatty aldehyde levels are poorly understood. Here, we report that ALH-4 is a C. elegans aldehyde dehydrogenase that specifically associates with the endoplasmic reticulum, mitochondria and peroxisomes. Based on lipidomic and imaging analysis, we show that the loss of ALH-4 increases fatty aldehyde levels and reduces fat storage. ALH-4 deficiency in the intestine, cell-nonautonomously induces NHR-49/NHR-79-dependent hypodermal peroxisome proliferation. This is accompanied by the upregulation of catalases and fatty acid catabolic enzymes, as indicated by RNA sequencing. Such a response is required to counteract ALH-4 deficiency since alh-4; nhr-49 double mutant animals are sterile. Our work reveals unexpected inter-tissue communication of fatty aldehyde levels and suggests pharmacological modulation of peroxisome proliferation as a therapeutic strategy to tackle pathology related to excess fatty aldehydes.


Assuntos
Aldeído Desidrogenase/genética , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Peroxissomos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Aldeído Desidrogenase/química , Aldeído Desidrogenase/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Regulação da Expressão Gênica , Lipase/genética , Lipase/metabolismo , Gotículas Lipídicas/metabolismo , Lipólise/genética , Mutação , Peroxissomos/genética , Receptores Citoplasmáticos e Nucleares/genética
5.
PeerJ ; 9: e10976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777524

RESUMO

BACKGROUND: The peanut (Arachis hypogaea) is a crop plant of high economic importance, but the epigenetic regulation of its root growth and development has not received sufficient attention. Research on Arabidopsis thaliana has shown that histone deacetylases (HDACs) are involved in cell growth, cell differentiation, and stress response. Few studies have focused on the role of HDACs in the root development of other plants, particularly crop plants. In earlier studies, we found large accumulations of A. hypogaea histone deacetylase 1 (AhHDA1) mRNA in peanut roots. However, we did not explore the role of AhHDA1 in peanut root development. METHODS: In this paper, we investigated the role of the peanut AhHDA1 gene and focused on the effect of altered AhHDA1 expression in hairy roots at both the phenotypic and transcriptional levels. We analyzed the transformation of A. hypogaea hairy roots using Agrobacterium rhizogenes and RNA sequencing to identify differentially expressed genes that were assigned to specific metabolic pathways. Transgenic hairy roots were used as experimental material to analyze the downstream genes expression and histone acetylation levels. To thoroughly understand AhHDA1 function, we also simultaneously screened the AhHDA1-interacting proteins using a yeast two-hybrid system. RESULTS: AhHDA1-overexpressing hairy roots were growth-retarded after 20 d in vitro cultivation, and they had a greater accumulation of superoxide anions and hydrogen peroxide than the control and RNAi groups. AhHDA1 overexpression in hairy roots accelerated flux through various secondary synthetic metabolic pathways, as well as inhibited the primary metabolism process. AhHDA1 overexpression also caused a significant upregulation of genes encoding the critical enzyme chalcone synthase (Araip.B8TJ0, CHS) in the flavonoid biosynthesis pathway, hydroxyisoflavanone synthase (Araip.0P3RJ) in the isoflavonoid biosynthesis pathway, and caffeoyl-CoA O-methyltransferase (Aradu.M62BY, CCoAOMT) in the phenylpropanoid biosynthesis pathway. In contrast, ferredoxin 1 (Araip.327XS), the polypeptide of the oxygen-evolving complex of photosystem II (Araip.N6ZTJ), and ribulose bisphosphate carboxylase (Aradu.5IY98) in the photosynthetic pathway were significantly downregulated by AhHDA1 overexpression. The expression levels of these genes had a positive correlation with histone acetylation levels. CONCLUSION: Our results revealed that the relationship between altered gene metabolism activities and AhHDA1 overexpression was mainly reflected in flavonoid, isoflavonoid, and phenylpropanoid metabolism. AhHDA1 overexpression retarded the growth of transgenic hairy roots and may be associated with cell metabolism status. Future studies should focus on the function of AhHDA1-interacting proteins and their effect on root development.

6.
Plant Sci ; 294: 110461, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32234234

RESUMO

Peanut (Arachis hypogaea L.) is an important crop that is adversely affected by drought. Post-drought growth is essential for improving peanut productivity and quality. Previous studies demonstrated that AhGLK1 (Arachis hypogaea L. Golden2-like 1) activates the expression of AhPORA to stimulate chlorophyll biosynthesis, and that AhGLK1 physically interacts with AhHDA1 (Arachis hypogaea L. histone deacetylase 1). However, the roles of the AhGLK1/AhHDA1 interaction in post-drought recovery remain to be elucidated. Herein, we report that AhHDA1 binds to AhGLK1 promoter and alters histone deacetylation levels to inhibit AhGLK1 expression. RNA-seq confirms that chlorophyll synthesis and photosynthesis-related genes are induced in AhGLK1-overexpressing, but reduced in AhGLK1 RNAi hairy roots. Furthermore, ChIP-seq shows that AhCAB (Arachis hypogaea L. chlorophyll A/B binding protein) is a target of both AhHDA1 and AhGLK1. Transactivation assays reveal that AhGLK1 activates AhCAB expression, while AhHDA1 inhibits the effect of AhGLK1 on AhCAB and AhPORA transcription. ChIP-qPCR shows that AhHDA1 and AhGLK1 bind to the promoters of AhCAB and AhPORA to regulate their expression during water stress and recovery. We propose that AhHDA1 and AhGLK1 consist of an ON/OFF switch for AhCAB and AhPORA expression during water stress and recovery. AhGLK1 activates, whereas AhHDA1 suppresses the expression of AhCAB and AhPORA.


Assuntos
Arachis/metabolismo , Clorofila/metabolismo , Fotossíntese/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Fotossíntese/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
7.
Life Sci Alliance ; 2(2)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30988161

RESUMO

Cell division requires constriction of an actomyosin ring to segregate the genetic material equally into two daughter cells. The spatial and temporal regulation of the contractile ring at the division plane primarily depends on intracellular signals mediated by the centralspindlin complex and astral microtubules. Although much investigative work has elucidated intracellular factors and mechanisms controlling this process, the extracellular regulation of cytokinesis remains unclear. Thus far, the extracellular matrix protein Hemicentin (HIM-4) has been proposed to be required for cleavage furrow stabilization. The underlying molecular mechanism, however, has remained largely unknown. Here, we show that HIM-4 and anillin (ANI-1) genetically act in the same pathway to maintain the rachis bridge stability in the germline. Our FRAP experiments further reveal that HIM-4 restricts the motility of ANI-1. In addition, we demonstrate that HIM-4 is recruited to the cleavage site in dividing germ cells and promotes the proper ingression of the cleavage membrane. Collectively, we propose that HIM-4 is an extracellular factor that regulates ANI-1 for germ cell membrane stabilization and contractile ring formation in Caenorhabditis elegans germline cells.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Proteínas Contráteis/metabolismo , Citocinese/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Células Germinativas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/metabolismo , Animais , Proteínas de Caenorhabditis elegans/genética , Membrana Celular/metabolismo , Segregação de Cromossomos/fisiologia , Escherichia coli/genética , Técnicas de Introdução de Genes , Proteínas dos Microfilamentos/genética , Interferência de RNA
8.
Biosci Trends ; 8(5): 286-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25382446

RESUMO

Albert Einstein's brain has long been an object of fascination to both neuroscience specialists and the general public. However, without records of advanced neuro-imaging of his brain, conclusions regarding Einstein's extraordinary cognitive capabilities can only be drawn based on the unique external features of his brain and through comparison of the external features with those of other human brain samples. The recent discovery of 14 previously unpublished photographs of Einstein's brain taken at unconventional angles by Dr. Thomas Stoltz Harvey, the pathologist, ignited a renewed frenzy about clues to explain Einstein's genius. Dr. Dean Falk and her colleagues, in their landmark paper published in Brain (2013; 136:1304-1327), described in such details about the unusual features of Einstein's brain, which shed new light on Einstein's intelligence. In this article, we ask what are the unique structures of his brain? What can we learn from this new information? Can we really explain his extraordinary cognitive capabilities based on these unique brain structures? We conclude that studying the brain of a remarkable person like Albert Einstein indeed provides us a better example to comprehensively appreciate the relationship between brain structures and advanced cognitive functions. However, caution must be exercised so as not to over-interpret his intelligence solely based on the understanding of the surface structures of his brain.


Assuntos
Encéfalo/anatomia & histologia , Pessoas Famosas , Inteligência , Encéfalo/fisiologia , Humanos , Neurociências/tendências
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