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1.
Cell ; 170(4): 736-747.e9, 2017 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-28802043

RESUMEN

Ants exhibit cooperative behaviors and advanced forms of sociality that depend on pheromone-mediated communication. Odorant receptor neurons (ORNs) express specific odorant receptors (ORs) encoded by a dramatically expanded gene family in ants. In most eusocial insects, only the queen can transmit genetic information, restricting genetic studies. In contrast, workers in Harpegnathos saltator ants can be converted into gamergates (pseudoqueens) that can found entire colonies. This feature facilitated CRISPR-Cas9 generation of germline mutations in orco, the gene that encodes the obligate co-receptor of all ORs. orco mutations should significantly impact olfaction. We demonstrate striking functions of Orco in odorant perception, reproductive physiology, and social behavior plasticity. Surprisingly, unlike in other insects, loss of OR functionality also dramatically impairs development of the antennal lobe to which ORNs project. Therefore, the development of genetics in Harpegnathos establishes this ant species as a model organism to study the complexity of eusociality.


Asunto(s)
Hormigas/crecimiento & desarrollo , Hormigas/genética , Proteínas de Insectos/genética , Receptores Odorantes/genética , Conducta Social , Secuencia de Aminoácidos , Animales , Hormigas/anatomía & histología , Hormigas/fisiología , Antenas de Artrópodos/anatomía & histología , Antenas de Artrópodos/metabolismo , Secuencia de Bases , Conducta Animal , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Femenino , Técnicas de Inactivación de Genes , Proteínas de Insectos/química , Masculino , Mutación , Feromonas/metabolismo , Receptores Odorantes/química
2.
Nature ; 620(7972): 72-77, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37168015

RESUMEN

A recent study demonstrated near-ambient superconductivity in nitrogen-doped lutetium hydride1. This stimulated a worldwide interest in exploring room-temperature superconductivity at low pressures. Here, by using a high-pressure and high-temperature synthesis technique, we have obtained nitrogen-doped lutetium hydride (LuH2±xNy), which has a dark-blue colour and a structure with the space group [Formula: see text] as evidenced by X-ray diffraction. This structure is the same as that reported in ref. 1, with a slight difference in lattice constant. Raman spectroscopy of our samples also showed patterns similar to those observed in ref. 1. Energy-dispersive X-ray spectroscopy confirmed the presence of nitrogen in the samples. We observed a metallic behaviour from 350 K to 2 K at ambient pressure. On applying pressures from 2.1 GPa to 41 GPa, we observed a gradual colour change from dark blue to violet to pink-red. By measuring the resistance at pressures ranging from 0.4 GPa to 40.1 GPa, we observed a progressively improved metallic behaviour; however, superconductivity was not observed above 2 K. Temperature dependence of magnetization at high pressure shows a very weak positive signal between 100 K and 320 K, and the magnetization increases with an increase in magnetic field at 100 K. All of these are not expected for superconductivity above 100 K. Thus, we conclude the absence of near-ambient superconductivity in this nitrogen-doped lutetium hydride at pressures below 40.1 GPa.

3.
Cell ; 153(5): 963-75, 2013 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-23706735

RESUMEN

The reprogramming factors that induce pluripotency have been identified primarily from embryonic stem cell (ESC)-enriched, pluripotency-associated factors. Here, we report that, during mouse somatic cell reprogramming, pluripotency can be induced with lineage specifiers that are pluripotency rivals to suppress ESC identity, most of which are not enriched in ESCs. We found that OCT4 and SOX2, the core regulators of pluripotency, can be replaced by lineage specifiers that are involved in mesendodermal (ME) specification and in ectodermal (ECT) specification, respectively. OCT4 and its substitutes attenuated the elevated expression of a group of ECT genes, whereas SOX2 and its substitutes curtailed a group of ME genes during reprogramming. Surprisingly, the two counteracting lineage specifiers can synergistically induce pluripotency in the absence of both OCT4 and SOX2. Our study suggests a "seesaw model" in which a balance that is established using pluripotency factors and/or counteracting lineage specifiers can facilitate reprogramming.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Factores de Transcripción/metabolismo , Animales , Células Madre Embrionarias/metabolismo , Fibroblastos/metabolismo , Factor de Transcripción GATA3/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/metabolismo , Ratones , Modelos Biológicos , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Estómago/citología
4.
Nature ; 602(7896): 229-233, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35140383

RESUMEN

Ultracold assembly of diatomic molecules has enabled great advances in controlled chemistry, ultracold chemical physics and quantum simulation with molecules1-3. Extending the ultracold association to triatomic molecules will offer many new research opportunities and challenges in these fields. A possible approach is to form triatomic molecules in a mixture of ultracold atoms and diatomic molecules by using a Feshbach resonance between them4,5. Although ultracold atom-diatomic-molecule Feshbach resonances have been observed recently6,7, using these resonances to form triatomic molecules remains challenging. Here we report on evidence of the association of triatomic molecules near the Feshbach resonance between 23Na40K molecules in the rovibrational ground state and 40K atoms. We apply a radio-frequency pulse to drive the free-bound transition in ultracold mixtures of 23Na40K and 40K and monitor the loss of 23Na40K molecules. The association of triatomic molecules manifests itself as an additional loss feature in the radio-frequency spectra, which can be distinguished from the atomic loss feature. The observation that the distance between the association feature and the atomic transition changes with the magnetic field provides strong evidence for the formation of triatomic molecules. The binding energy of the triatomic molecules is estimated from the measurements. Our work contributes to the understanding of the complex ultracold atom-molecule Feshbach resonances and may open up an avenue towards the preparation and control of ultracold triatomic molecules.

5.
Immunity ; 49(4): 740-753.e7, 2018 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-30314759

RESUMEN

Caspase-11, a cytosolic endotoxin (lipopolysaccharide: LPS) receptor, mediates pyroptosis, a lytic form of cell death. Caspase-11-dependent pyroptosis mediates lethality in endotoxemia, but it is unclear how LPS is delivered into the cytosol for the activation of caspase-11. Here we discovered that hepatocyte-released high mobility group box 1 (HMGB1) was required for caspase-11-dependent pyroptosis and lethality in endotoxemia and bacterial sepsis. Mechanistically, hepatocyte-released HMGB1 bound LPS and targeted its internalization into the lysosomes of macrophages and endothelial cells via the receptor for advanced glycation end-products (RAGE). Subsequently, HMGB1 permeabilized the phospholipid bilayer in the acidic environment of lysosomes. This resulted in LPS leakage into the cytosol and caspase-11 activation. Depletion of hepatocyte HMGB1, inhibition of hepatocyte HMGB1 release, neutralizing extracellular HMGB1, or RAGE deficiency prevented caspase-11-dependent pyroptosis and death in endotoxemia and bacterial sepsis. These findings indicate that HMGB1 interacts with LPS to mediate caspase-11-dependent pyroptosis in lethal sepsis.


Asunto(s)
Caspasas/inmunología , Endotoxinas/inmunología , Proteína HMGB1/inmunología , Piroptosis/inmunología , Sepsis/inmunología , Animales , Caspasas/genética , Caspasas/metabolismo , Células Cultivadas , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Endotoxinas/metabolismo , Células HEK293 , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Humanos , Lipopolisacáridos/inmunología , Lipopolisacáridos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor para Productos Finales de Glicación Avanzada/inmunología , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Sepsis/genética , Sepsis/metabolismo , Células THP-1
6.
Semin Cell Dev Biol ; 155(Pt B): 32-44, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-37507331

RESUMEN

Angiogenesis is vital to developmental, regenerative and repair processes. It is normally regulated by a balanced production of pro- and anti-angiogenic factors. Alterations in this balance under pathological conditions are generally mediated through up-regulation of pro-angiogenic and/or downregulation of anti-angiogenic factors, leading to growth of new and abnormal blood vessels. The pathological manifestation of many diseases including cancer, ocular and vascular diseases are dependent on the growth of these new and abnormal blood vessels. Thrompospondin-1 (TSP1) was the first endogenous angiogenesis inhibitor identified and its anti-angiogenic and anti-inflammatory activities have been the subject of many studies. Studies examining the role TSP1 plays in pathogenesis of various ocular diseases and vascular dysfunctions are limited. Here we will discuss the recent studies focused on delineating the role TSP1 plays in ocular vascular development and homeostasis, and pathophysiology of various ocular and vascular diseases with a significant clinical relevance to human health.


Asunto(s)
Neoplasias , Enfermedades Vasculares , Humanos , Neoplasias/patología , Neovascularización Patológica/patología
7.
Bioessays ; 46(6): e2300243, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38593284

RESUMEN

The autophagy initiation complex is brought about via a highly ordered and stepwise assembly process. Two crucial signaling molecules, mTORC1 and AMPK, orchestrate this assembly by phosphorylating/dephosphorylating autophagy-related proteins. Activation of Atg1 followed by recruitment of both Atg9 vesicles and the PI3K complex I to the PAS (phagophore assembly site) are particularly crucial steps in its formation. Ypt1, a small Rab GTPase in yeast cells, also plays an essential role in the formation of the autophagy initiation complex through multiple regulatory pathways. In this review, our primary focus is to discuss how signaling molecules initiate the assembly of the autophagy initiation complex, and highlight the significant roles of Ypt1 in this process. We end by addressing issues that need future clarification.


Asunto(s)
Proteínas Relacionadas con la Autofagia , Autofagia , Diana Mecanicista del Complejo 1 de la Rapamicina , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Transducción de Señal , Proteínas de Unión al GTP rab , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas Relacionadas con la Autofagia/genética , Proteínas de Unión al GTP rab/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Humanos , Animales , Proteínas Quinasas Activadas por AMP/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Complejos Multiproteicos/metabolismo
8.
Hum Genomics ; 18(1): 43, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38659056

RESUMEN

OBJECTIVE: Myasthenia gravis (MG) is a complex autoimmune disease affecting the neuromuscular junction with limited drug options, but the field of MG treatment recently benefits from novel biological agents. We performed a drug-targeted Mendelian randomization (MR) study to identify novel therapeutic targets of MG. METHODS: Cis-expression quantitative loci (cis-eQTL), which proxy expression levels for 2176 druggable genes, were used for MR analysis. Causal relationships between genes and disease, identified by eQTL MR analysis, were verified by comprehensive sensitivity, colocalization, and protein quantitative loci (pQTL) MR analyses. The protein-protein interaction (PPI) analysis was also performed to extend targets, followed by enzyme-linked immunosorbent assay (ELISA) to explore the serum level of drug targets in MG patients. A phenome-wide MR analysis was then performed to assess side effects with a clinical trial review assessing druggability. RESULTS: The eQTL MR analysis has identified eight potential targets for MG, one for early-onset MG and seven for late-onset MG. Further colocalization analyses indicated that CD226, CDC42BPB, PRSS36, and TNFSF12 possess evidence for colocalization with MG or late-onset MG. pQTL MR analyses identified the causal relations of TNFSF12 and CD226 with MG and late-onset MG. Furthermore, PPI analysis has revealed the protein interaction between TNFSF12-TNFSF13(APRIL) and TNFSF12-TNFSF13B(BLyS). Elevated TNFSF13 serum level of MG patients was also identified by ELISA experiments. This study has ultimately proposed three promising therapeutic targets (TNFSF12, TNFSF13, TNFSF13B) of MG. CONCLUSIONS: Three drug targets associated with the BLyS/APRIL pathway have been identified. Multiple biological agents, including telitacicept and belimumab, are promising for MG therapy.


Asunto(s)
Análisis de la Aleatorización Mendeliana , Miastenia Gravis , Sitios de Carácter Cuantitativo , Humanos , Miastenia Gravis/genética , Miastenia Gravis/tratamiento farmacológico , Miastenia Gravis/patología , Miastenia Gravis/sangre , Sitios de Carácter Cuantitativo/genética , Mapas de Interacción de Proteínas/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética
10.
Proc Natl Acad Sci U S A ; 119(20): e2202812119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35533282

RESUMEN

Developing facile approaches for preparing efficient electrocatalysts is of significance to promote sustainable energy technologies. Here, we report a facile iron-oxidizing bacteria corrosion approach to construct a composite electrocatalyst of nickel­iron oxyhydroxides combined with iron oxides. The obtained electrocatalyst shows improved electrocatalytic activity and stability for oxygen evolution, with an overpotential of ∼230 mV to afford the current density of 10 mA cm−2. The incorporation of iron oxides produced by iron-oxidizing bacteria corrosion optimizes the electronic structure of nickel­iron oxyhydroxide electrodes, which accounts for the decreased free energy of oxygenate generation and the improvement of OER activity. This work demonstrates a natural bacterial corrosion approach for the facile preparation of efficient electrodes for water oxidation, which may provide interesting insights in the multidisciplinary integration of innovative nanomaterials and emerging energy technologies.


Asunto(s)
Níquel , Oxígeno , Microbiología del Agua , Corrosión , Compuestos Férricos , Hierro , Agua
11.
J Cell Mol Med ; 28(8): e18275, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38568058

RESUMEN

Breast cancer (BC) remains a significant health concern worldwide, with metastasis being a primary contributor to patient mortality. While advances in understanding the disease's progression continue, the underlying mechanisms, particularly the roles of long non-coding RNAs (lncRNAs), are not fully deciphered. In this study, we examined the influence of the lncRNA LINC00524 on BC invasion and metastasis. Through meticulous analyses of TCGA and GEO data sets, we observed a conspicuous elevation of LINC00524 expression in BC tissues. This increased expression correlated strongly with a poorer prognosis for BC patients. A detailed Gene Ontology analysis suggested that LINC00524 likely exerts its effects through RNA-binding proteins (RBPs) mechanisms. Experimentally, LINC00524 was demonstrated to amplify BC cell migration, invasion and proliferation in vitro. Additionally, in vivo tests showed its potent role in promoting BC cell growth and metastasis. A pivotal discovery was LINC00524's interaction with TDP43, which leads to the stabilization of TDP43 protein expression, an element associated with unfavourable BC outcomes. In essence, our comprehensive study illuminates how LINC00524 accelerates BC invasion and metastasis by binding to TDP43, presenting potential avenues for therapeutic interventions.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Femenino , Humanos , Bioensayo , Neoplasias de la Mama/genética , Transformación Celular Neoplásica , Ontología de Genes , ARN Largo no Codificante/genética
12.
Neuroimage ; 290: 120580, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38508294

RESUMEN

Diagnosis of disorders of consciousness (DOC) remains a formidable challenge. Deep learning methods have been widely applied in general neurological and psychiatry disorders, while limited in DOC domain. Considering the successful use of resting-state functional MRI (rs-fMRI) for evaluating patients with DOC, this study seeks to explore the conjunction of deep learning techniques and rs-fMRI in precisely detecting awareness in DOC. We initiated our research with a benchmark dataset comprising 140 participants, including 76 unresponsive wakefulness syndrome (UWS), 25 minimally conscious state (MCS), and 39 Controls, from three independent sites. We developed a cascade 3D EfficientNet-B3-based deep learning framework tailored for discriminating MCS from UWS patients, referred to as "DeepDOC", and compared its performance against five state-of-the-art machine learning models. We also included an independent dataset consists of 11 DOC patients to test whether our model could identify patients with cognitive motor dissociation (CMD), in which DOC patients were behaviorally diagnosed unconscious but could be detected conscious by brain computer interface (BCI) method. Our results demonstrate that DeepDOC outperforms the five machine learning models, achieving an area under curve (AUC) value of 0.927 and accuracy of 0.861 for distinguishing MCS from UWS patients. More importantly, DeepDOC excels in CMD identification, achieving an AUC of 1 and accuracy of 0.909. Using gradient-weighted class activation mapping algorithm, we found that the posterior cortex, encompassing the visual cortex, posterior middle temporal gyrus, posterior cingulate cortex, precuneus, and cerebellum, as making a more substantial contribution to classification compared to other brain regions. This research offers a convenient and accurate method for detecting covert awareness in patients with MCS and CMD using rs-fMRI data.


Asunto(s)
Trastornos de la Conciencia , Aprendizaje Profundo , Humanos , Encéfalo/diagnóstico por imagen , Estado Vegetativo Persistente , Inconsciencia , Estado de Conciencia
13.
Am J Physiol Endocrinol Metab ; 326(5): E723-E734, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38506753

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of beta cells by immune cells. The interactions among cells within the islets may be closely linked to the pathogenesis of T1D. In this study, we used single-cell RNA sequencing (scRNA-Seq) to analyze the cellular heterogeneity within the islets of a T1D mouse model. We established a T1D mouse model induced by streptozotocin and identified cell subpopulations using scRNA-Seq technology. Our results revealed 11 major cell types in the pancreatic islets of T1D mice, with heterogeneity observed in the alpha and beta cell subgroups, which may play a crucial role in the progression of T1D. Flow cytometry further confirmed a mature alpha and beta cell reduction in T1D mice. Overall, our scRNA-Seq analysis provided insights into the cellular heterogeneity of T1D islet tissue and highlighted the potential importance of alpha and beta cells in developing T1D.NEW & NOTEWORTHY In this study, we created a comprehensive single-cell atlas of pancreatic islets in a T1D mouse model using scRNA-Seq and identified 11 major cell types in the islets, highlighting the role of alpha and beta cells in T1D. This study revealed a significant reduction in the maturity alpha and beta cells in T1D mice through flow cytometry. It also demonstrated the heterogeneity of alpha and beta cells, potentially crucial for T1D progression. Overall, our scRNA-Seq analysis provided new insights for understanding and treating T1D by studying cell subtype changes and functions.


Asunto(s)
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Islotes Pancreáticos , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Animales , Ratones , Diabetes Mellitus Tipo 1/genética , Análisis de la Célula Individual/métodos , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/citología , Células Secretoras de Insulina/metabolismo , Análisis de Secuencia de ARN/métodos , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Células Secretoras de Glucagón/metabolismo , Femenino , RNA-Seq/métodos , Ratones Endogámicos C57BL
14.
Small ; : e2401215, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856003

RESUMEN

Sodium batteries (SBs) emerge as a potential candidate for large-scale energy storage and have become a hot topic in the past few decades. In the previous researches on electrolyte, designing electrolytes with the solvation theory has been the most promising direction is to improve the electrochemical performance of batteries through solvation theory. In general, the four essential factors for the commercial application of SBs, which are cost, low temperature performance, fast charge performance and safety. The solvent structure has significant impact on commercial applications. But so far, the solvation design of electrolyte and the practical application of sodium batteries have not been comprehensively summarized. This review first clarifies the process of Na+ solvation and the strategies for adjusting Na+ solvation. It is worth noting that the relationship between solvation theory and interface theory is pointed out. The cost, low temperature, fast charging, and safety issues of solvation are systematically summarized. The importance of the de-solvation step in low temperature and fast charging application is emphasized to help select better electrolytes for specific applications. Finally, new insights and potential solutions for electrolytes solvation related to SBs are proposed to stimulate revolutionary electrolyte chemistry for next generation SBs.

15.
J Virol ; 97(5): e0165822, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37071015

RESUMEN

Japanese encephalitis virus (JEV), with neurotoxic and neuroinvasive properties, is the major cause of human viral encephalitis in Asia. Although Guillain-Barré syndrome caused by JEV infections is not frequent, a few cases have been reported in recent years. To date, no existing animal model for JEV-induced peripheral nerve injury (PNI) has been established, and thus the pathogenic mechanism is not clarified. Therefore, an animal model is urgently required to clarify the correlation between JEV infection and PNI. In the present study, we used JEV GIb strain of NX1889 to establish a mouse model of JEV infection. The general neurological signs emerged on day 3 of modeling. The motor function continued to deteriorate, reaching a maximum at 8 to 13 days postinfection (dpi) and gradually recovered after 16 dpi. The injuries of 105 PFU and 106 PFU groups were the most severe. Transmission electron microscopy and immunofluorescence staining showed varying degrees of demyelination and axonal degeneration in the sciatic nerves. The electrophysiological recordings demonstrated the presence of demyelinating peripheral neuropathy with reduced nerve conduction velocity. The decreased amplitudes and the prolonged end latency revealed axonal-type motor neuropathy. Demyelination is predominant in the early stage, followed by axonal injury. The expression level of JEV-E protein and viral RNA was elevated in the injured sciatic nerves, suggesting that it may cause PNI at the early stage. Inflammatory cell infiltration and increased inflammatory cytokines indicated that neuroinflammation is involved in JEV-induced PNI. IMPORTANCE JEV is a neurotropic flavivirus belonging to the Flaviviridae family and causes high mortality and disability rates. It invades the central nervous system and induces acute inflammatory injury and neuronal death. Thus, JEV infection is a major global public health concern. Previously, motor dysfunction was mainly attributed to central nervous system damage. Our knowledge regarding JEV-induced PNI is vague and neglected. Therefore, a laboratory animal model is essential. Herein, we showed that C57BL/6 mice can be used to study JEV-induced PNI through multiple approaches. We also demonstrated that viral loads might be positively correlated with lesion severity. Therefore, inflammation and direct virus infection may be the putative mechanisms underlying JEV-induced PNI. The results of this study laid the foundation for further elucidation of the pathogenesis mechanisms of PNI caused by JEV.


Asunto(s)
Modelos Animales de Enfermedad , Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Traumatismos de los Nervios Periféricos , Animales , Humanos , Ratones , Enfermedades Desmielinizantes , Virus de la Encefalitis Japonesa (Especie)/fisiología , Ratones Endogámicos C57BL
16.
J Transl Med ; 22(1): 183, 2024 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378668

RESUMEN

BACKGROUND: Myasthenia gravis (MG) and the experimental autoimmune MG (EAMG) animal model are characterized by T-cell-induced and B-cell-dominated autoimmune diseases that affect the neuromuscular junction. Several subtypes of CD4+ T cells, including T helper (Th) 17 cells, follicular Th cells, and regulatory T cells (Tregs), contribute to the pathogenesis of MG. However, increasing evidence suggests that CD8+ T cells also play a critical role in the pathogenesis and treatment of MG. MAIN BODY: Herein, we review the literature on CD8+ T cells in MG, focusing on their potential effector and regulatory roles, as well as on relevant evidence (peripheral, in situ, cerebrospinal fluid, and under different treatments), T-cell receptor usage, cytokine and chemokine expression, cell marker expression, and Treg, Tc17, CD3+CD8+CD20+ T, and CXCR5+ CD8+ T cells. CONCLUSIONS: Further studies on CD8+ T cells in MG are necessary to determine, among others, the real pattern of the Vß gene usage of autoantigen-specific CD8+ cells in patients with MG, real images of the physiology and function of autoantigen-specific CD8+ cells from MG/EAMG, and the subset of autoantigen-specific CD8+ cells (Tc1, Tc17, and IL-17+IFN-γ+CD8+ T cells). There are many reports of CD20-expressing T (or CD20 + T) and CXCR5+ CD8 T cells on autoimmune diseases, especially on multiple sclerosis and rheumatoid arthritis. Unfortunately, up to now, there has been no report on these T cells on MG, which might be a good direction for future studies.


Asunto(s)
Linfocitos T CD8-positivos , Miastenia Gravis Autoinmune Experimental , Animales , Humanos , Linfocitos T Colaboradores-Inductores/metabolismo , Miastenia Gravis Autoinmune Experimental/metabolismo , Linfocitos T Reguladores , Autoantígenos/metabolismo
17.
J Transl Med ; 22(1): 132, 2024 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310289

RESUMEN

BACKGROUND: The current precision medicine relies on biomarkers, which are mainly obtained through next-generation sequencing (NGS). However, this model failed to find effective drugs for most cancer patients. This study tried to combine liquid biopsy with functional drug tests using organoid models to find potential drugs for cancer patients. METHODS: Colorectal cancer (CRC) patients were prospectively enrolled and blood samples were collected from patients before the start of treatment. Targeted deep sequencing of cfDNA samples was performed using a 14-gene panel. Gastrointestinal (GI) cancer organoids were established and PI3K and mTOR inhibitors were evaluated on organoid models. RESULTS: A total of 195 mutations were detected across 58 cfDNA samples. The most frequently mutated genes were KRAS, TP53, PIK3CA, and BRAF, all of which exhibited higher mutation rates than tissue biopsy. Although 81% of variants had an allele frequency of less than 1%, certain mutations in KRAS, TP53, and SMAD4 had high allele frequencies exceeding 10%. Notably, among the seven patients with high allele frequency mutations, six had metastatic tumors, indicating that a high allele frequency of ctDNA could potentially serve as a biomarker of later-stage cancer. A high rate of PIK3CA mutation (31 out of 67, or 46.3%) was discovered in CRC patients, suggesting possible tumor progression mechanisms and targeted therapy opportunities. To evaluate the value of anti PI3K strategy in GI cancer, different lines of GI cancer organoids were established. The organoids recapitulated the morphologies of the original tumors. Organoids were generally insensitive to PI3K inhibitors. However, CRC-3 and GC-4 showed response to mTOR inhibitor Everolimus, and GC-3 was sensitive to PI3Kδ inhibitor Idelalisib. The CRC organoid with a PIK3CA mutation showed greater sensitivity to the PI3K inhibitor Alpelisib than wildtype organoids, suggesting potential treatment options for the corresponding patients. CONCLUSION: Liquid biopsy holds significant promise for improving precision treatment and tumor prognosis in colorectal cancer patients. The combination of biomarker-based drug prediction with organoid-based functional drug sensitivity assay may lead to more effective cancer treatment.


Asunto(s)
Ácidos Nucleicos Libres de Células , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/diagnóstico , Fosfatidilinositol 3-Quinasas/genética , Evaluación Preclínica de Medicamentos , Proteínas Proto-Oncogénicas p21(ras)/genética , Detección Precoz del Cáncer , Biopsia Líquida , Inhibidores de las Quinasa Fosfoinosítidos-3 , Biomarcadores , Fosfatidilinositol 3-Quinasa Clase I/genética , Mutación/genética
18.
Appl Environ Microbiol ; : e0054024, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829054

RESUMEN

Halophilic archaea are promising microbial cell factories for bacterioruberin (BR) production. BR is a natural product with multi-bioactivities, allowing potential application in many fields. In the previous work, a haloarchaeon Halorubrum sp. HRM-150 with a high proportion of BR (about 85%) was isolated, but the low yield impeded its large-scale production. This work figured out BR synthesis characteristics and mechanisms, and proposed strategies for yield improvement. First, glucose (10 g/L) and tryptone (15 g/L) were tested to be better sources for BR production. Besides, the combination of glucose and starch achieved the diauxic growth, and the biomass and BR productivity increased by 85% and 54% than using glucose. Additionally, this work first proposed the BR synthesis pattern, which differs from that of other carotenoids. As a structural component of cell membranes, the BR synthesis is highly coupled with growth, which was most active in the logarithm phase. Meanwhile, the osmotic down shock at the logarithm phase could increase the BR productivity without sacrificing the biomass. Moreover, the de-novo pathway for BR synthesis with a key gene of lyeJ, and its competitive pathways (notably tetraether lipids and retinal) were revealed through genome, transcriptome, and osmotic down shock. Therefore, the BR yield is expected to be improved through mutant construction, such as the overexpression of key gene lyeJ and the knockout of competitive genes, which need to be further explored. The findings will contribute to a better understanding of the metabolism mechanism in haloarchaea and the development of haloarchaea as microbial cell factories. IMPORTANCE: Recent studies have revealed that halophilic microorganism is a promising microbial factory for the next-generation industrialization. Among them, halophilic archaea are advantageous as microbial factories due to their low contamination risk and low freshwater consumption. The halophilic archaea usually accumulate long chain C50 carotenoids, which are barely found in other organisms. Bacterioruberin (BR), the major C50 carotenoid, has multi-bioactivities, allowing potential application in food, cosmetic, and biomedical industries. However, the low yield impedes its large-scale application. This work figured out the BR synthesis characteristics and mechanism, and proposed several strategies for BR yield improvement, encouraging halophilic archaea to function as microbial factories for BR production. Meanwhile, the archaea have special evolutionary status and unique characteristics in taxonomy, the revelation of BR biosynthesis mechanism is beneficial for a better understanding of archaea.

19.
New Phytol ; 241(4): 1662-1675, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38058237

RESUMEN

Ribosome biogenesis is a highly dynamic and orchestrated process facilitated by hundreds of ribosomal biogenesis factors and small nucleolar RNAs. While many of the advances are derived from studies in yeast, ribosome biogenesis remains largely unknown in plants despite its importance to plant growth and development. Through characterizing the maize (Zea mays) defective kernel and embryo-lethal mutant dek58, we show that DEK58 encodes an Rrp15p domain-containing protein with 15.3% identity to yeast Rrp15. Over-expression of DEK58 rescues the mutant phenotype. DEK58 is localized in the nucleolus. Ribosome profiling and RNA gel blot analyses show that the absence of DEK58 reduces ribosome assembly and impedes pre-rRNA processing, accompanied by the accumulation of nearly all the pre-rRNA processing intermediates and the production of an aberrant processing product P-25S*. DEK58 interacts with ZmSSF1, a maize homolog of the yeast Ssf1 in the 60S processome. DEK58 and ZmSSF1 interact with ZmCK2α, a putative component of the yeast UTP-C complex involved in the small ribosomal subunit processome. These results demonstrate that DEK58 is essential to seed development in maize. It functions in the early stage of pre-rRNA processing in ribosome biogenesis, possibly through interacting with ZmSSF1 and ZmCK2α in maize.


Asunto(s)
ARN Ribosómico , Zea mays , Zea mays/genética , Zea mays/metabolismo , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Precursores del ARN/genética , Precursores del ARN/metabolismo , Ribosomas/metabolismo , Semillas/genética , Semillas/metabolismo , Procesamiento Postranscripcional del ARN/genética
20.
Blood ; 139(21): 3181-3193, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35040907

RESUMEN

Anemia of inflammation, also known as anemia of chronic disease, is refractory to erythropoietin (EPO) treatment, but the mechanisms underlying the EPO refractory state are unclear. Here, we demonstrate that high mobility group box-1 protein (HMGB1), a damage-associated molecular pattern molecule recently implicated in anemia development during sepsis, leads to reduced expansion and increased death of EPO-sensitive erythroid precursors in human models of erythropoiesis. HMGB1 significantly attenuates EPO-mediated phosphorylation of the Janus kinase 2/STAT5 and mTOR signaling pathways. Genetic ablation of receptor for advanced glycation end products, the only known HMGB1 receptor expressed by erythroid precursors, does not rescue the deleterious effects of HMGB1 on EPO signaling, either in human or murine precursors. Furthermore, surface plasmon resonance studies highlight the ability of HMGB1 to interfere with the binding between EPO and the EPOR. Administration of a monoclonal anti-HMGB1 antibody after sepsis onset in mice partially restores EPO signaling in vivo. Thus, HMGB1-mediated restriction of EPO signaling contributes to the chronic phase of anemia of inflammation.


Asunto(s)
Anemia , Eritropoyetina , Proteína HMGB1 , Sepsis , Anemia/genética , Animales , Eritropoyesis/genética , Eritropoyetina/metabolismo , Inflamación , Ratones , Receptores de Eritropoyetina/metabolismo , Sepsis/complicaciones
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