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1.
Nature ; 633(8031): 828-834, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39322733

RESUMEN

Climate warming has caused a widespread increase in extreme fire weather, making forest fires longer-lived and larger1-3. The average forest fire size in Canada, the USA and Australia has doubled or even tripled in recent decades4,5. In return, forest fires feed back to climate by modulating land-atmospheric carbon, nitrogen, aerosol, energy and water fluxes6-8. However, the surface climate impacts of increasingly large fires and their implications for land management remain to be established. Here we use satellite observations to show that in temperate and boreal forests in the Northern Hemisphere, fire size persistently amplified decade-long postfire land surface warming in summer per unit burnt area. Both warming and its amplification with fire size were found to diminish with an increasing abundance of broadleaf trees, consistent with their lower fire vulnerability compared with coniferous species9,10. Fire-size-enhanced warming may affect the success and composition of postfire stand regeneration11,12 as well as permafrost degradation13, presenting previously overlooked, additional feedback effects to future climate and fire dynamics. Given the projected increase in fire size in northern forests14,15, climate-smart forestry should aim to mitigate the climate risks of large fires, possibly by increasing the share of broadleaf trees, where appropriate, and avoiding active pyrophytes.


Asunto(s)
Retroalimentación , Bosques , Calentamiento Global , Calor , Árboles , Incendios Forestales , Agricultura Forestal/métodos , Agricultura Forestal/tendencias , Calentamiento Global/estadística & datos numéricos , Estaciones del Año , Taiga , Árboles/anatomía & histología , Árboles/clasificación , Árboles/crecimiento & desarrollo , Árboles/metabolismo , Incendios Forestales/estadística & datos numéricos , Factores de Tiempo
2.
Nature ; 624(7992): 672-681, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37935376

RESUMEN

Trace-amine-associated receptors (TAARs), a group of biogenic amine receptors, have essential roles in neurological and metabolic homeostasis1. They recognize diverse endogenous trace amines and subsequently activate a range of G-protein-subtype signalling pathways2,3. Notably, TAAR1 has emerged as a promising therapeutic target for treating psychiatric disorders4,5. However, the molecular mechanisms underlying its ability to recognize different ligands remain largely unclear. Here we present nine cryo-electron microscopy structures, with eight showing human and mouse TAAR1 in a complex with an array of ligands, including the endogenous 3-iodothyronamine, two antipsychotic agents, the psychoactive drug amphetamine and two identified catecholamine agonists, and one showing 5-HT1AR in a complex with an antipsychotic agent. These structures reveal a rigid consensus binding motif in TAAR1 that binds to endogenous trace amine stimuli and two extended binding pockets that accommodate diverse chemotypes. Combined with mutational analysis, functional assays and molecular dynamic simulations, we elucidate the structural basis of drug polypharmacology and identify the species-specific differences between human and mouse TAAR1. Our study provides insights into the mechanism of ligand recognition and G-protein selectivity by TAAR1, which may help in the discovery of ligands or therapeutic strategies for neurological and metabolic disorders.


Asunto(s)
Proteínas de Unión al GTP , Receptores Acoplados a Proteínas G , Animales , Humanos , Ratones , Aminas/metabolismo , Anfetamina/metabolismo , Antipsicóticos/química , Antipsicóticos/metabolismo , Sitios de Unión , Catecolaminas/agonistas , Catecolaminas/química , Catecolaminas/metabolismo , Microscopía por Crioelectrón , Proteínas de Unión al GTP/química , Proteínas de Unión al GTP/metabolismo , Proteínas de Unión al GTP/ultraestructura , Ligandos , Simulación de Dinámica Molecular , Mutación , Polifarmacología , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/ultraestructura , Especificidad de la Especie , Especificidad por Sustrato
3.
PLoS Biol ; 22(8): e3002763, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39133741

RESUMEN

Phenotypic plasticity displayed by an animal in response to different environmental conditions is supposedly crucial for its survival and reproduction. The female adults of some ant lineages display phenotypic plasticity related to reproductive role. In pharaoh ant queens, insemination induces substantial physiological/behavioral changes and implicates remarkable gene regulatory network (GRN) shift in the brain. Here, we report a neuropeptide neuroparsin A (NPA) showing a conserved expression pattern associated with reproductive activity across ant species. Knock-down of NPA in unmated queen enhances ovary activity, whereas injection of NPA peptide in fertilized queen suppresses ovary activity. We found that NPA mainly affected the downstream gene JHBP in the ovary, which is positively regulated by NPA and suppression of which induces elevated ovary activity, and shadow which is negatively regulated by NPA. Furthermore, we show that NPA was also employed into the brain-ovary axis in regulating the worker reproductive changes in other distantly related species, such as Harpegnathos venator ants.


Asunto(s)
Hormigas , Neuropéptidos , Reproducción , Animales , Hormigas/fisiología , Hormigas/genética , Hormigas/metabolismo , Reproducción/fisiología , Femenino , Neuropéptidos/metabolismo , Neuropéptidos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Ovario/metabolismo , Ovario/fisiología , Encéfalo/metabolismo , Encéfalo/fisiología , Evolución Biológica , Redes Reguladoras de Genes
4.
Nature ; 589(7841): 293-298, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33299182

RESUMEN

H1 linker histones are the most abundant chromatin-binding proteins1. In vitro studies indicate that their association with chromatin determines nucleosome spacing and enables arrays of nucleosomes to fold into more compact chromatin structures. However, the in vivo roles of H1 are poorly understood2. Here we show that the local density of H1 controls the balance of repressive and active chromatin domains by promoting genomic compaction. We generated a conditional triple-H1-knockout mouse strain and depleted H1 in haematopoietic cells. H1 depletion in T cells leads to de-repression of T cell activation genes, a process that mimics normal T cell activation. Comparison of chromatin structure in normal and H1-depleted CD8+ T cells reveals that H1-mediated chromatin compaction occurs primarily in regions of the genome containing higher than average levels of H1: the chromosome conformation capture (Hi-C) B compartment and regions of the Hi-C A compartment marked by PRC2. Reduction of H1 stoichiometry leads to decreased H3K27 methylation, increased H3K36 methylation, B-to-A-compartment shifting and an increase in interaction frequency between compartments. In vitro, H1 promotes PRC2-mediated H3K27 methylation and inhibits NSD2-mediated H3K36 methylation. Mechanistically, H1 mediates these opposite effects by promoting physical compaction of the chromatin substrate. Our results establish H1 as a critical regulator of gene silencing through localized control of chromatin compaction, 3D genome organization and the epigenetic landscape.


Asunto(s)
Ensamble y Desensamble de Cromatina , Cromatina/genética , Epigénesis Genética , Histonas/metabolismo , Animales , Linfocitos T CD8-positivos/metabolismo , Diferenciación Celular/genética , Cromatina/química , Cromatina/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Femenino , Silenciador del Gen , Histonas/química , Activación de Linfocitos/genética , Masculino , Metilación , Ratones , Ratones Noqueados
5.
Plant Cell ; 35(10): 3739-3756, 2023 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-37367221

RESUMEN

The biological function of RNA can be modulated by base modifications. Here, we unveiled the occurrence of N4-acetylation of cytidine in plant RNA, including mRNA, by employing LC-MS/MS and acRIP-seq. We identified 325 acetylated transcripts from the leaves of 4-week-old Arabidopsis (Arabidopsis thaliana) plants and determined that 2 partially redundant N-ACETYLTRANSFERASEs FOR CYTIDINE IN RNA (ACYR1 and ACYR2), which are homologous to mammalian NAT10, are required for acetylating RNA in vivo. A double-null mutant was embryo lethal, while eliminating 3 of the 4 ACYR alleles led to defects in leaf development. These phenotypes could be traced back to the reduced acetylation and concomitant destabilization of the transcript of TOUGH, which is required for miRNA processing. These findings indicate that N4-acetylation of cytidine is a modulator of RNA function with a critical role in plant development and likely many other processes.


Asunto(s)
Arabidopsis , Citidina , Animales , ARN Mensajero/genética , Acetilación , Citidina/genética , Citidina/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , ARN de Planta , Arabidopsis/genética , Arabidopsis/metabolismo , Mamíferos/genética , Mamíferos/metabolismo
6.
Chem Rev ; 124(4): 1992-2079, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38335114

RESUMEN

Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These materials establish a new central research area and provide a promising platform for studying quantum phenomena and investigating the engineering of novel optoelectronic properties such as single photon emission, nonlinear optical response, magnon physics, and topological superconductivity. These captivating electronic and optical properties result from, and can be tailored by, the interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding properties and the high degree of tunability position them as compelling building blocks for both compact quantum-enabled devices and classical optoelectronics. This paper offers a comprehensive review of recent advancements in the understanding and manipulation of twisted van der Waals structures and presents a survey of the state-of-the-art research on moiré superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis and fabrication, and visualization techniques, and the wide range of novel physical phenomena exhibited by these structures, with a focus on their potential for practical device integration in applications ranging from quantum information to biosensors, and including classical optoelectronics such as modulators, light emitting diodes, lasers, and photodetectors. It highlights the unique ability of moiré superlattices to connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, topological and quantum physics. This comprehensive review provides a valuable resource for researchers interested in moiré superlattices, shedding light on their fundamental characteristics and their potential for transformative applications in various fields.

7.
J Virol ; 98(8): e0022324, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39046246

RESUMEN

Porcine circovirus type 3 (PCV3) is closely associated with various diseases, such as the porcine dermatitis, nephropathy syndrome, and multisystemic clinicopathological diseases. PCV3-associated diseases are increasingly recognized as severe diseases in the global swine industry. Ring finger protein 2 (RNF2), an E3 ubiquitin ligase exclusively located in the nucleus, contributes to various biological processes. This ligase interacts with the PCV3 Cap. However, its role in PCV3 replication remains unclear. This study confirmed that the nuclear localization signal domain of the Cap and the RNF2 N-terminal RING domain facilitate the interaction between the Cap and RNF2. Furthermore, RNF2 promoted the binding of K48-linked polyubiquitination chains to lysine at positions 139 and 140 (K139 and K140) of the PCV3 Cap, thereby degrading the Cap. RNF2 knockdown and overexpression increased or decreased PCV3 replication, respectively. Moreover, the RING domain-deleted RNF2 mutant eliminated the RNF2-induced degradation of the PCV3 Cap and RNF2-mediated inhibition of viral replication. This indicates that both processes were associated with its E3 ligase activity. Our findings demonstrate that RNF2 can interact with and degrade the PCV3 Cap via its N-terminal RING domain in a ubiquitination-dependent manner, thereby inhibiting PCV3 replication.IMPORTANCEPorcine circovirus type 3 is a recently described pathogen that is prevalent worldwide, causing substantial economic losses to the swine industry. However, the mechanisms through which host proteins regulate its replication remain unclear. Here, we demonstrate that ring finger protein 2 inhibits porcine circovirus type 3 replication by interacting with and degrading the Cap of this pathogen in a ubiquitination-dependent manner, requiring its N-terminal RING domain. Ring finger protein 2-mediated degradation of the Cap relies on its E3 ligase activity and the simultaneous existence of K139 and K140 within the Cap. These findings reveal the mechanism by which this protein interacts with and degrades the Cap to inhibit porcine circovirus type 3 replication. This consequently provides novel insights into porcine circovirus type 3 pathogenesis and facilitates the development of preventative measures against this pathogen.


Asunto(s)
Proteínas de la Cápside , Circovirus , Ubiquitina-Proteína Ligasas , Ubiquitinación , Replicación Viral , Circovirus/genética , Circovirus/metabolismo , Circovirus/fisiología , Animales , Porcinos , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas de la Cápside/metabolismo , Proteínas de la Cápside/genética , Humanos , Células HEK293 , Proteolisis , Línea Celular , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/metabolismo , Infecciones por Circoviridae/virología , Infecciones por Circoviridae/metabolismo , Unión Proteica
8.
Mol Psychiatry ; 29(5): 1491-1500, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38273109

RESUMEN

Microbial infection as a type of environmental risk factors is considered to be associated with long-term increased risk of dementia, including Alzheimer's disease (AD). AD is characterized by two neuropathologically molecular hallmarks of hyperphosphorylated tau and amyloid-ß (Aß), the latter generated by several biochemically reactive enzymes, including γ-secretase. However, how infectious risk factors contribute to pathological development of the AD core molecules remains to be addressed. In this work, we utilized a modified herpes simplex virus type 1 (mHSV-1) and found that its hippocampal infection locally promotes Aß pathology in 5 × FAD mice, the commonly used amyloid model. Mechanistically, we identified HSV-1 membrane glycoprotein US7 (Envelope gI) that interacts with and modulates γ-secretase and consequently facilitates Aß production. Furthermore, we presented evidence that adenovirus-associated virus-mediated locally hippocampal overexpression of the US7 aggravates Aß pathology in 5 × FAD mice. Collectively, these findings identify a herpesviral factor regulating γ-secretase in the development and progression of AD and represent a causal molecular link between infectious pathogens and neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer , Secretasas de la Proteína Precursora del Amiloide , Péptidos beta-Amiloides , Modelos Animales de Enfermedad , Herpesvirus Humano 1 , Hipocampo , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Ratones , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Hipocampo/metabolismo , Hipocampo/patología , Herpesvirus Humano 1/metabolismo , Herpesvirus Humano 1/patogenicidad , Ratones Transgénicos , Humanos , Amiloide/metabolismo , Proteínas tau/metabolismo , Ratones Endogámicos C57BL
9.
Exp Cell Res ; 442(2): 114260, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39303839

RESUMEN

Vascular smooth muscle cell (VSMC) excessive proliferation and migration are considered the main pathological process in in-stent restenosis (ISR) following vascular intervention. Certain long noncoding RNAs play vital roles in this process. Therefore, this study aimed to explore novel regulators for ISR and further uncover the mechanism. Using a rat abdominal aorta stent implantation model, we observed that NONRATT000538.2 (NR538.2) served as a positive regulator for VSMC proliferation and migration. By manipulating NR538.2 expression via adenoviral overexpression or siRNA knockdown, we noted that NR538.2 promoted VSMC phenotypic switching, thereby inducing proliferation and migration. Significantly, the local delivery of siRNA of NR538.2 via adeno-associated virus vector suppressed balloon injury-induced neointima formation. Our study demonstrated for the first time that NR538.2 positively influenced VSMC proliferation during ISR.

10.
Exp Cell Res ; 439(1): 114076, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38719174

RESUMEN

Glioblastoma (GBM) is a common primary central nervous system tumor. The molecular mechanisms of glioma are unknown, and the prognosis is poor. Therefore, exploring the underlying mechanisms and screening for new prognostic markers and therapeutic targets is crucial. We utilized the weighted gene co-expression network analysis (WGCNA), Differentially Expressed Genes (DEGs), and LASSO-COX analysis to identify three target genes. Next, we constructed and evaluated a prognostic model, screening out COL8A1 as a risk gene. Through a sequence of cellular functional experiments, in vivo studies, and RNA sequencing, we delved into exploring the functional effects and molecular mechanisms of COL8A1 on GBM cells. Finally, the correlation between COL8A1 and tumor immune cells and different inflammatory responses was analyzed. Immunohistochemistry experiments revealed the influence of COL8A1 on macrophage polarization. The COL8A1 expression level was associated with the grade, prognosis, and tumor microenvironment (TME) of glioma. Functional experiments showed that COL8A1 inhibited GBM cell apoptosis and promoted migration, invasion, and proliferation in vitro and in vivo. We also found that COL8A1 promotes the epithelial-mesenchymal transition process and may mediate the activation of the ERK pathway through SHC1. In addition, immune infiltration analysis showed that COL8A1 was closely associated with macrophages in glioma tissues, significantly suppressing the signaling of M1-like -type macrophages and enhancing the signaling of M2-like -type macrophages. COL8A1 was first found to be associated with prognosis, progression, and immune microenvironment of glioma and may serve as a new marker of prognosis and a therapeutic target.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Encefálicas , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioma , Microambiente Tumoral , Animales , Femenino , Humanos , Masculino , Ratones , Apoptosis/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transición Epitelial-Mesenquimal/genética , Glioblastoma/patología , Glioblastoma/genética , Glioblastoma/metabolismo , Glioma/genética , Glioma/patología , Glioma/metabolismo , Ratones Desnudos , Pronóstico , Microambiente Tumoral/genética
11.
Proc Natl Acad Sci U S A ; 119(36): e2203057119, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36037375

RESUMEN

Phosphorus (P) is a key nutrient limiting bacterial growth and primary production in the oceans. Unsurprisingly, marine microbes have evolved sophisticated strategies to adapt to P limitation, one of which involves the remodeling of membrane lipids by replacing phospholipids with non-P-containing surrogate lipids. This strategy is adopted by both cosmopolitan marine phytoplankton and heterotrophic bacteria and serves to reduce the cellular P quota. However, little, if anything, is known of the biological consequences of lipid remodeling. Here, using the marine bacterium Phaeobacter sp. MED193 and the ciliate Uronema marinum as a model, we sought to assess the effect of remodeling on bacteria-protist interactions. We discovered an important trade-off between either escape from ingestion or resistance to digestion. Thus, Phaeobacter grown under P-replete conditions was readily ingested by Uronema, but not easily digested, supporting only limited predator growth. In contrast, following membrane lipid remodeling in response to P depletion, Phaeobacter was less likely to be captured by Uronema, thanks to the reduced expression of mannosylated glycoconjugates. However, once ingested, membrane-remodeled cells were unable to prevent phagosome acidification, became more susceptible to digestion, and, as such, allowed rapid growth of the ciliate predator. This trade-off between adapting to a P-limited environment and susceptibility to protist grazing suggests the more efficient removal of low-P prey that potentially has important implications for the functioning of the marine microbial food web in terms of trophic energy transfer and nutrient export efficiency.


Asunto(s)
Cadena Alimentaria , Modelos Biológicos , Fósforo , Organismos Acuáticos , Cilióforos/fisiología , Lípidos de la Membrana/metabolismo , Fosfolípidos/metabolismo , Fósforo/metabolismo , Fitoplancton/metabolismo , Rhodobacteraceae/fisiología
12.
Gut ; 73(9): 1543-1553, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-38724220

RESUMEN

OBJECTIVE: Previous studies indicate that eosinophils are recruited into the allograft following orthotopic liver transplantation and protect from ischaemia reperfusion (IR) injury. In the current studies, we aim to explore whether their protective function could outlast during liver repair. DESIGN: Eosinophil-deficient mice and adoptive transfer of bone marrow-derived eosinophils (bmEos) were employed to investigate the effects of eosinophils on tissue repair and regeneration after hepatic IR injury. Aside from exogenous cytokine or neutralising antibody treatments, mechanistic studies made use of a panel of mouse models of eosinophil-specific IL-4/IL-13-deletion, cell-specific IL-4rα-deletion in liver macrophages and hepatocytes and macrophage-specific deletion of heparin-binding epidermal growth factor-like growth factor (hb-egf). RESULT: We observed that eosinophils persisted over a week following hepatic IR injury. Their peak accumulation coincided with that of hepatocyte proliferation. Functional studies showed that eosinophil deficiency was associated with a dramatic delay in liver repair, which was normalised by the adoptive transfer of bmEos. Mechanistic studies demonstrated that eosinophil-derived IL-4, but not IL-13, was critically involved in the reparative function of these cells. The data further revealed a selective role of macrophage-dependent IL-4 signalling in liver regeneration. Eosinophil-derived IL-4 stimulated macrophages to produce HB-EGF. Moreover, macrophage-specific hb-egf deletion impaired hepatocyte regeneration after IR injury. CONCLUSION: Together, these studies uncovered an indispensable role of eosinophils in liver repair after acute injury and identified a novel crosstalk between eosinophils and macrophages through the IL-4/HB-EGF axis.


Asunto(s)
Eosinófilos , Factor de Crecimiento Similar a EGF de Unión a Heparina , Interleucina-4 , Regeneración Hepática , Macrófagos , Daño por Reperfusión , Animales , Factor de Crecimiento Similar a EGF de Unión a Heparina/metabolismo , Factor de Crecimiento Similar a EGF de Unión a Heparina/genética , Regeneración Hepática/fisiología , Daño por Reperfusión/metabolismo , Interleucina-4/metabolismo , Ratones , Eosinófilos/metabolismo , Macrófagos/metabolismo , Hígado/patología , Hígado/metabolismo , Hígado/irrigación sanguínea , Hepatocitos/metabolismo , Interleucina-13/metabolismo , Traslado Adoptivo , Ratones Endogámicos C57BL
13.
J Cell Mol Med ; 28(7): e18172, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38494837

RESUMEN

M1 macrophage polarization and synovitis play an important role in the pathogenesis of temporomandibular joint osteoarthritis (TMJOA). Reduced molecular weight of hyaluronic acid (HA) in synovial fluid of patients with TMJOA. In addition, high molecular weight hyaluronic acid (HMW-HA) is often used clinically to treat TMJ inflammation. As a pattern recognition receptor of the cytoplasm, ALPK1 was found to be pro-inflammatory in a variety of diseases. However, the relationship of ALPK1, HA and M1 macrophage polarization in TMJ synovitis remains unclear. We aimed to investigate the role of ALPK1 and HA in macrophage polarization and TMJ synovitis and the underlying mechanisms. The results demonstrated that ALPK1 was highly upregulated in the synovial macrophages in the inflamed TMJ synovium of patients. Low molecular weight hyaluronic acid (LMW-HA) promoted the expression of ALPK1 and M1 macrophage-associated genes. Besides, rhALPK1 promoted the expression of M1 macrophage-associated factors and the nuclear translocation of PKM2. Furthermore, ALPK1 knockout mice exhibited limited infiltration of macrophages and decreased expression levels of M1 macrophage-associated genes in CFA-induced TMJ synovitis. While HMW-HA inhibited the expression of ALPK1 and M1 macrophage polarization. Our results elucidated that ALPK1 promoted TMJ synovitis by promoting nuclear PKM2-mediated M1 macrophage polarization, whereas HMW-HA inhibited the expression of ALPK1 as well as M1 macrophage polarization.


Asunto(s)
Osteoartritis , Sinovitis , Humanos , Animales , Ratones , Ácido Hialurónico , Sinovitis/patología , Articulación Temporomandibular/patología , Inflamación/patología , Osteoartritis/metabolismo , Macrófagos/metabolismo , Proteínas Quinasas
14.
BMC Genomics ; 25(1): 462, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38735952

RESUMEN

BACKGROUND: Detecting epistatic interactions (EIs) involves the exploration of associations among single nucleotide polymorphisms (SNPs) and complex diseases, which is an important task in genome-wide association studies. The EI detection problem is dependent on epistasis models and corresponding optimization methods. Although various models and methods have been proposed to detect EIs, identifying EIs efficiently and accurately is still a challenge. RESULTS: Here, we propose a linear mixed statistical epistasis model (LMSE) and a spherical evolution approach with a feedback mechanism (named SEEI). The LMSE model expands the existing single epistasis models such as LR-Score, K2-Score, Mutual information, and Gini index. The SEEI includes an adaptive spherical search strategy and population updating strategy, which ensures that the algorithm is not easily trapped in local optima. We analyzed the performances of 8 random disease models, 12 disease models with marginal effects, 30 disease models without marginal effects, and 10 high-order disease models. The 60 simulated disease models and a real breast cancer dataset were used to evaluate eight algorithms (SEEI, EACO, EpiACO, FDHEIW, MP-HS-DHSI, NHSA-DHSC, SNPHarvester, CSE). Three evaluation criteria (pow1, pow2, pow3), a T-test, and a Friedman test were used to compare the performances of these algorithms. The results show that the SEEI algorithm (order 1, averages ranks = 13.125) outperformed the other algorithms in detecting EIs. CONCLUSIONS: Here, we propose an LMSE model and an evolutionary computing method (SEEI) to solve the optimization problem of the LMSE model. The proposed method performed better than the other seven algorithms tested in its ability to identify EIs in genome-wide association datasets. We identified new SNP-SNP combinations in the real breast cancer dataset and verified the results. Our findings provide new insights for the diagnosis and treatment of breast cancer. AVAILABILITY AND IMPLEMENTATION: https://github.com/scutdy/SSO/blob/master/SEEI.zip .


Asunto(s)
Algoritmos , Neoplasias de la Mama , Epistasis Genética , Modelos Genéticos , Polimorfismo de Nucleótido Simple , Humanos , Neoplasias de la Mama/genética , Estudio de Asociación del Genoma Completo
15.
Immunology ; 171(4): 566-582, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38158796

RESUMEN

The spleen is essential for lymphocyte proliferation, which is associated to sepsis prognosis. Adenosine 2A receptor (A2AR) blocking promotes lymphocyte proliferation in sepsis, however the mechanism is uncertain. Our sepsis cecum ligation perforation model showed that blocking A2AR increased survival and CD4+ cell numbers in a spleen-dependent mechanism. The sequencing of the transcriptome of the spleen indicated alterations in the expression of genes involved in the control of lymphocyte proliferation by inhibiting A2AR, including a reduction in the expression of PD-L1. Flow cytometry analysis of PD-L1 expression intensity in splenic cell subpopulations revealed that the Treg cell subpopulation was the strongest PD-L1-expressing cell population, and Treg PD-L1 expression decreased after blocking A2AR. In vitro activation of A2AR was able to upregulate PD-L1 expression of Treg and boost Treg capacity to limit lymphocyte proliferation, while blockage of PD-L1 partly reduced A2AR-activated Treg's ability to inhibit lymphocyte proliferation. In addition, blocking CREB phosphorylation significantly inhibited A2AR-induced PD-L1 expression. According to the findings of our research, inhibiting A2AR improves the prognosis of sepsis by lowering the level of PD-L1 expression by Treg in the spleen and reducing the inhibition of lymphocyte proliferation.


Asunto(s)
Sepsis , Bazo , Humanos , Bazo/metabolismo , Linfocitos T Reguladores/metabolismo , Antagonistas de Receptores Purinérgicos P1 , Antígeno B7-H1/metabolismo , Adenosina , Proliferación Celular
16.
J Am Chem Soc ; 146(4): 2615-2623, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38117537

RESUMEN

Herpes simplex virus-1 (HSV-1) utilizes multiple viral surface glycoproteins to trigger virus entry and fusion. Among these glycoproteins, glycoprotein D (gD) functions as a receptor-binding protein, which makes it an attractive target for the development of vaccines against HSV-1 infection. Several recombinant gD subunit vaccines have been investigated in both preclinical and clinical phases with varying degrees of success. It is fundamentally critical to explore the functions of gD glycans. In light of this, we report an efficient synthetic platform to construct glycosylated gDs bearing homogeneous glycans at N94 and N121. The oligosaccharides were prepared by enzymatic synthesis and conjugated to peptidyl sectors. The glycoproteins were constructed via a combination of 7-(piperazin-1-yl)-2-(methyl)quinolinyl (PPZQ)-assisted expressed protein ligation and ß-mercapto amino acid-assisted-desulfurization strategies. Biological studies showed that synthetic gDs exhibited potent in vivo activity in mice.


Asunto(s)
Infecciones por Herpesviridae , Herpesvirus Humano 1 , Animales , Ratones , Herpesvirus Humano 1/metabolismo , Proteínas del Envoltorio Viral/metabolismo , Glicoproteínas/metabolismo , Polisacáridos/metabolismo
17.
J Am Chem Soc ; 146(15): 10847-10856, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38583085

RESUMEN

Transition-metal-catalyzed carbene insertion reactions of a nitrogen-hydrogen bond have emerged as robust and versatile methods for the construction of C-N bonds. While significant progress of homogeneous catalytic metal carbene N-H insertions has been achieved, the control of chemoselectivity in the field remains challenging due to the high electrophilicity of the metal carbene intermediates. Herein, we present an efficient strategy for the synthesis of a rhodium single-atom-site catalyst (Rh-SA) that incorporates a Rh atom surrounded by three nitrogen atoms and one phosphorus atom doped in a carbon support. This Rh-SA catalyst, with a catalyst loading of only 0.15 mol %, exhibited exceptional catalytic performance for heterogeneous carbene insertion with various anilines and heteroaryl amines in combination with diazo esters. Importantly, the heterogeneous catalyst selectively transformed aniline derivatives bearing multiple nucleophilic moieties into single N-H insertion isomers, while the popular homogeneous Rh2(OAc)4 catalyst produced a mixture of overfunctionalized side products. Additionally, similar selectivities for N-H bond insertion with a set of stereoelectronically diverse diazo esters were obtained, highlighting the general applicability of this heterogeneous catalysis approach. On the basis of density functional theory calculations, the observed selectivity of the Rh-SA catalyst was attributed to the insertion barriers and the accelerated proton transfer assisted by the phosphorus atom in the support. Overall, this investigation of heterogeneous metal-catalyzed carbene insertion underscores the potential of single-atom-site catalysis as a powerful and complementary tool in organic synthesis.

18.
Apoptosis ; 29(9-10): 1793-1809, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39222275

RESUMEN

Lung cancer is one of the most common malignant tumors. Despite decades of research, the treatment of lung cancer remains challenging. Non-small cell lung cancer (NSCLC) is the primary type of lung cancer and is a significant focus of research in lung cancer treatment. The deubiquitinase ubiquitin-specific protease 28 (USP28) plays a role in the progression of various tumors and serves as a potential therapeutic target. This study aims to determine the role of USP28 in the progression of NSCLC. We examined the impact of the USP28 inhibitor AZ1 on the cell cycle, apoptosis, DNA damage response, and cellular immunogenicity in non-small cell lung cancer. We observed that AZ1 and siUSP28 induce DNA damage, leading to the activation of Noxa-mediated mitochondrial apoptosis. The dsDNA and mtDNA released from DNA damage and mitochondrial apoptosis activate tumor cell immunogenicity through the cGAS-STING signaling pathway. Simultaneously, targeting USP28 promotes the degradation of c-MYC, resulting in cell cycle arrest and inhibition of DNA repair. This further promotes DNA damage-induced cell apoptosis mediated by the Noxa protein, thereby enhancing tumor cell immunogenicity mediated by dsDNA and mtDNA. Moreover, we found that the combination of AZ1 and cisplatin (DDP) can enhance therapeutic efficacy, thereby providing a new strategy to overcome cisplatin resistance in NSCLC. These findings suggest that targeting USP28 and combining it with cisplatin are feasible strategies for treating NSCLC.


Asunto(s)
Apoptosis , Carcinoma de Pulmón de Células no Pequeñas , Cisplatino , Daño del ADN , Neoplasias Pulmonares , Ubiquitina Tiolesterasa , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Cisplatino/farmacología , Cisplatino/uso terapéutico , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Animales , Ratones , Transducción de Señal/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Desnudos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Piperidonas
19.
Apoptosis ; 2024 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-39394530

RESUMEN

Myocardial fibrosis is a typical pathological manifestation of hypertension. However, the exact role of sirtuin 7 (SIRT7) in myocardial remodeling remains largely unclear. Here, spontaneously hypertensive rats (SHRs) and angiotensin (Ang) II-induced hypertensive mice were pretreated with recombinant adeno-associated virus (rAAV)-SIRT7, copper chelator tetrathiomolybdate (TTM) or copper ionophore elesclomol, respectively. Compared with normotensive controls, reduced SIRT7 expression and augmented cuproptosis were observed in hearts of hypertensive rats and mice with decreased FDX1 levels and increased HSP70 levels. Notably, intervention with rAAV-SIRT7 and TTM strikingly prevented DLAT oligomers aggregation, and elevated ATP7A and TOM20 expressions, contributing to the alleviation of cuproptosis, mitochondrial injury, myocardial remodeling and heart dysfunction in spontaneously hypertensive rats and Ang II-induced hypertensive mice. In cultured rat primary cardiac fibroblasts (CFs), rhSIRT7 alleviated CuCl2, Ang II or elesclomol-induced cuproptosis and fibroblast activation by blunting DLAT oligomers accumulation and downregulating α-SMA expression. Additionally, conditioned medium from rhSIRT7-pretreated CFs remarkably mitigated cellular hypertrophy and mitochondrial impairments of neonatal rat cardiomyocytes, as well as cell migration and polarization of RAW 264.7 macrophages. Importantly, verteporfin reduced CuCl2-induced cuproptosis, mitochondrial injury and fibrotic activation in CFs. Knockdown of ATP7A with si-ATP7A blocked cellular protective effects of rhSIRT7 and verteporfin in CFs. In conclusion, SIRT7 attenuates cuproptosis, myocardial fibrosis and heart dysfunction in hypertension through the modulation of YAP/ATP7A signaling. Targeting SIRT7 is of vital importance for developing therapeutic strategies in hypertension and hypertensive heart disorders.

20.
Clin Immunol ; 265: 110298, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38909972

RESUMEN

Prostaglandins (PGs) play a crucial and multifaceted role in various physiological processes such as intercellular signaling, inflammation regulation, neurotransmission, vasodilation, vasoconstriction, and reproductive functions. The diversity and biological significance of these effects are contingent upon the specific types or subtypes of PGs, with each PG playing a crucial role in distinct physiological and pathological processes. Particularly within the immune system, PGs are essential in modulating the function of immune cells and the magnitude and orientation of immune responses. Hence, a comprehensive comprehension of the functions PG signaling pathways in immunosuppressive regulation holds substantial clinical relevance for disease prevention and treatment strategies. The manuscript provides a review of recent developments in PG signaling in immunosuppressive regulation. Furthermore, the potential clinical applications of PGs in immunosuppression are also discussed. While research into the immunosuppressive effects of PGs required further exploration, targeted therapies against their immunosuppressive pathways might open new avenues for disease prevention and treatment.


Asunto(s)
Terapia de Inmunosupresión , Prostaglandinas , Transducción de Señal , Humanos , Prostaglandinas/inmunología , Prostaglandinas/metabolismo , Animales , Transducción de Señal/inmunología , Tolerancia Inmunológica
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