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1.
Cell ; 174(2): 481-496.e19, 2018 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-30007419

RESUMEN

Dopamine (DA) is a central monoamine neurotransmitter involved in many physiological and pathological processes. A longstanding yet largely unmet goal is to measure DA changes reliably and specifically with high spatiotemporal precision, particularly in animals executing complex behaviors. Here, we report the development of genetically encoded GPCR-activation-based-DA (GRABDA) sensors that enable these measurements. In response to extracellular DA, GRABDA sensors exhibit large fluorescence increases (ΔF/F0 ∼90%) with subcellular resolution, subsecond kinetics, nanomolar to submicromolar affinities, and excellent molecular specificity. GRABDA sensors can resolve a single-electrical-stimulus-evoked DA release in mouse brain slices and detect endogenous DA release in living flies, fish, and mice. In freely behaving mice, GRABDA sensors readily report optogenetically elicited nigrostriatal DA release and depict dynamic mesoaccumbens DA signaling during Pavlovian conditioning or during sexual behaviors. Thus, GRABDA sensors enable spatiotemporally precise measurements of DA dynamics in a variety of model organisms while exhibiting complex behaviors.


Asunto(s)
Dopamina/análisis , Drosophila/metabolismo , Pez Cebra/metabolismo , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/metabolismo , Conducta Animal , Dopamina/metabolismo , Femenino , Proteínas Fluorescentes Verdes/genética , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Neuronas/citología , Neuronas/metabolismo , Optogenética/métodos , Receptores Acoplados a Proteínas G/genética , Canales Catiónicos TRPV/genética , Proteínas de Pez Cebra/genética
2.
Plant Cell ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801738

RESUMEN

Virus-induced drought tolerance presents a fascinating facet of biotic-abiotic interaction in plants, yet its molecular intricacies remain unclear. Our study shows that cowpea mild mottle virus (CPMMV) infection enhances drought tolerance in common bean (Phaseolus vulgaris) plants through a virus-derived small interfering RNA (vsiRNA)-activated autophagy pathway. Specifically, a 21-bp vsiRNA originating from the CPMMV Triple Gene Block1 (TGB1) gene targeted the 5' untranslated region (UTR) of the host Teosinte branched 1, Cycloidea, Proliferating Cell Factor (TCP) transcription factor gene PvTCP2, independent of the known role of TGB1 as an RNA silencing suppressor. This targeting attenuated the expression of PvTCP2, which encodes a transcriptional repressor, and in turn upregulated the core autophagy-related gene (ATG) PvATG8c, leading to activated autophagy activity surpassing the level induced by drought or CPMMV infection alone. The downstream EARLY RESPONSIVE TO DEHYDRATION (ERD) effector PvERD15 is a homologue of Arabidopsis thaliana AtERD15, which positively regulates stomatal aperture. PvERD15 was degraded in PvATG8c-mediated autophagy. Therefore, we establish a TGB1-PvTCP2-PvATG8c-PvERD15 module as a trans-kingdom fine-tuning mechanism that contributes to virus-induced drought tolerance in plant-drought-virus interactions.

3.
Nature ; 591(7848): 131-136, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33472215

RESUMEN

Plasma membrane rupture (PMR) is the final cataclysmic event in lytic cell death. PMR releases intracellular molecules known as damage-associated molecular patterns (DAMPs) that propagate the inflammatory response1-3. The underlying mechanism of PMR, however, is unknown. Here we show that the cell-surface NINJ1 protein4-8, which contains two transmembrane regions, has an essential role in the induction of PMR. A forward-genetic screen of randomly mutagenized mice linked NINJ1 to PMR. Ninj1-/- macrophages exhibited impaired PMR in response to diverse inducers of pyroptotic, necrotic and apoptotic cell death, and were unable to release numerous intracellular proteins including HMGB1 (a known DAMP) and LDH (a standard measure of PMR). Ninj1-/- macrophages died, but with a distinctive and persistent ballooned morphology, attributable to defective disintegration of bubble-like herniations. Ninj1-/- mice were more susceptible than wild-type mice to infection with Citrobacter rodentium, which suggests a role for PMR in anti-bacterial host defence. Mechanistically, NINJ1 used an evolutionarily conserved extracellular domain for oligomerization and subsequent PMR. The discovery of NINJ1 as a mediator of PMR overturns the long-held idea that cell death-related PMR is a passive event.


Asunto(s)
Moléculas de Adhesión Celular Neuronal/metabolismo , Muerte Celular , Membrana Celular/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Animales , Apoptosis , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/genética , Muerte Celular/genética , Femenino , Humanos , Macrófagos , Masculino , Ratones , Mutación , Necrosis , Factores de Crecimiento Nervioso/química , Factores de Crecimiento Nervioso/genética , Multimerización de Proteína , Piroptosis/genética
4.
Proc Natl Acad Sci U S A ; 121(22): e2316176121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38771878

RESUMEN

The striato-nigral (Str-SN) circuit is composed of medium spiny neuronal projections that are mainly sent from the striatum to the midbrain substantial nigra (SN), which is essential for regulating motor behaviors. Dysfunction of the Str-SN circuitry may cause a series of motor disabilities that are associated with neurodegenerative disorders, such as Huntington's disease (HD). Although the etiology of HD is known as abnormally expanded CAG repeats of the huntingtin gene, treatment of HD remains tremendously challenging. One possible reason is the lack of effective HD model that resembles Str-SN circuitry deficits for pharmacological studies. Here, we first differentiated striatum-like organoids from human pluripotent stem cells (hPSCs), containing functional medium spiny neurons (MSNs). We then generated 3D Str-SN assembloids by assembling striatum-like organoids with midbrain SN-like organoids. With AAV-hSYN-GFP-mediated viral tracing, extensive MSN projections from the striatum to the SN are established, which formed synaptic connection with GABAergic neurons in SN organoids and showed the optically evoked inhibitory postsynaptic currents and electronic field potentials by labeling the striatum-like organoids with optogenetic virus. Furthermore, these Str-SN assembloids exhibited enhanced calcium activity compared to that of individual striatal organoids. Importantly, we further demonstrated the reciprocal projection defects in HD iPSC-derived assembloids, which could be ameliorated by treatment of brain-derived neurotrophic factor. Taken together, these findings suggest that Str-SN assembloids could be used for identifying MSN projection defects and could be applied as potential drug test platforms for HD.


Asunto(s)
Enfermedad de Huntington , Organoides , Humanos , Enfermedad de Huntington/patología , Enfermedad de Huntington/metabolismo , Organoides/patología , Organoides/metabolismo , Sustancia Negra/patología , Sustancia Negra/metabolismo , Cuerpo Estriado/patología , Cuerpo Estriado/metabolismo , Neuronas/metabolismo , Neuronas/patología , Diferenciación Celular , Neuronas GABAérgicas/metabolismo , Neuronas GABAérgicas/patología , Células Madre Pluripotentes/metabolismo , Optogenética
5.
Nat Immunol ; 15(2): 161-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24362890

RESUMEN

CD11b(+) dendritic cells (DCs) seem to be specialized for presenting antigens via major histocompatibility (MHC) class II complexes to stimulate helper T cells, but the genetic and regulatory basis for this is not established. Conditional deletion of Irf4 resulted in loss of CD11b(+) DCs, impaired formation of peptide-MHC class II complexes and defective priming of helper T cells but not of cytotoxic T lymphocyte (CTL) responses. Gene expression and chromatin immunoprecipitation followed by deep sequencing (ChIP-Seq) analyses delineated an IRF4-dependent regulatory module that programs enhanced MHC class II antigen presentation. Expression of the transcription factor IRF4 but not of IRF8 restored the ability of IRF4-deficient DCs to efficiently process and present antigen to MHC class II-restricted T cells and promote helper T cell responses. We propose that the evolutionary divergence of IRF4 and IRF8 facilitated the specialization of DC subsets for distinct modes of antigen presentation and priming of helper T cell versus CTL responses.


Asunto(s)
Presentación de Antígeno/genética , Células Dendríticas/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Factores Reguladores del Interferón/metabolismo , Linfocitos T Citotóxicos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Cultivadas , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Factores Reguladores del Interferón/genética , Activación de Linfocitos/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Unión Proteica/genética , Transgenes/genética
6.
Blood ; 143(18): 1825-1836, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38211332

RESUMEN

ABSTRACT: Venetoclax, the first-generation inhibitor of the apoptosis regulator B-cell lymphoma 2 (BCL2), disrupts the interaction between BCL2 and proapoptotic proteins, promoting the apoptosis in malignant cells. Venetoclax is the mainstay of therapy for relapsed chronic lymphocytic leukemia and is under investigation in multiple clinical trials for the treatment of various cancers. Although venetoclax treatment can result in high rates of durable remission, relapse has been widely observed, indicating the emergence of drug resistance. The G101V mutation in BCL2 is frequently observed in patients who relapsed treated with venetoclax and sufficient to confer resistance to venetoclax by interfering with compound binding. Therefore, the development of next-generation BCL2 inhibitors to overcome drug resistance is urgently needed. In this study, we discovered that sonrotoclax, a potent and selective BCL2 inhibitor, demonstrates stronger cytotoxic activity in various hematologic cancer cells and more profound tumor growth inhibition in multiple hematologic tumor models than venetoclax. Notably, sonrotoclax effectively inhibits venetoclax-resistant BCL2 variants, such as G101V. The crystal structures of wild-type BCL2/BCL2 G101V in complex with sonrotoclax revealed that sonrotoclax adopts a novel binding mode within the P2 pocket of BCL2 and could explain why sonrotoclax maintains stronger potency than venetoclax against the G101V mutant. In summary, sonrotoclax emerges as a potential second-generation BCL2 inhibitor for the treatment of hematologic malignancies with the potential to overcome BCL2 mutation-induced venetoclax resistance. Sonrotoclax is currently under investigation in multiple clinical trials.


Asunto(s)
Antineoplásicos , Compuestos Bicíclicos Heterocíclicos con Puentes , Resistencia a Antineoplásicos , Neoplasias Hematológicas , Proteínas Proto-Oncogénicas c-bcl-2 , Sulfonamidas , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Sulfonamidas/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Animales , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Mutación , Apoptosis/efectos de los fármacos
7.
Nature ; 587(7833): 275-280, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32971525

RESUMEN

Mutations in the death receptor FAS1,2 or its ligand FASL3 cause autoimmune lymphoproliferative syndrome, whereas mutations in caspase-8 or its adaptor FADD-which mediate cell death downstream of FAS and FASL-cause severe immunodeficiency in addition to autoimmune lymphoproliferative syndrome4-6. Mouse models have corroborated a role for FADD-caspase-8 in promoting inflammatory responses7-12, but the mechanisms that underlie immunodeficiency remain undefined. Here we identify NEDD4-binding protein 1 (N4BP1) as a suppressor of cytokine production that is cleaved and inactivated by caspase-8. N4BP1 deletion in mice increased the production of select cytokines upon stimulation of the Toll-like receptor (TLR)1-TLR2 heterodimer (referred to herein as TLR1/2), TLR7 or TLR9, but not upon engagement of TLR3 or TLR4. N4BP1 did not suppress TLR3 or TLR4 responses in wild-type macrophages, owing to TRIF- and caspase-8-dependent cleavage of N4BP1. Notably, the impaired production of cytokines in response to TLR3 and TLR4 stimulation of caspase-8-deficient macrophages13 was largely rescued by co-deletion of N4BP1. Thus, the persistence of intact N4BP1 in caspase-8-deficient macrophages impairs their ability to mount robust cytokine responses. Tumour necrosis factor (TNF), like TLR3 or TLR4 agonists, also induced caspase-8-dependent cleavage of N4BP1, thereby licensing TRIF-independent TLRs to produce higher levels of inflammatory cytokines. Collectively, our results identify N4BP1 as a potent suppressor of cytokine responses; reveal N4BP1 cleavage by caspase-8 as a point of signal integration during inflammation; and offer an explanation for immunodeficiency caused by mutations of FADD and caspase-8.


Asunto(s)
Caspasa 8/metabolismo , Citocinas/inmunología , Inmunidad Innata/inmunología , Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Animales , Células Cultivadas , Citocinas/antagonistas & inhibidores , Humanos , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Receptor Toll-Like 3/metabolismo , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
8.
Nature ; 584(7821): 479-483, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32788728

RESUMEN

Lipopolysaccharide (LPS) resides in the outer membrane of Gram-negative bacteria where it is responsible for barrier function1,2. LPS can cause death as a result of septic shock, and its lipid A core is the target of polymyxin antibiotics3,4. Despite the clinical importance of polymyxins and the emergence of multidrug resistant strains5, our understanding of the bacterial factors that regulate LPS biogenesis is incomplete. Here we characterize the inner membrane protein PbgA and report that its depletion attenuates the virulence of Escherichia coli by reducing levels of LPS and outer membrane integrity. In contrast to previous claims that PbgA functions as a cardiolipin transporter6-9, our structural analyses and physiological studies identify a lipid A-binding motif along the periplasmic leaflet of the inner membrane. Synthetic PbgA-derived peptides selectively bind to LPS in vitro and inhibit the growth of diverse Gram-negative bacteria, including polymyxin-resistant strains. Proteomic, genetic and pharmacological experiments uncover a model in which direct periplasmic sensing of LPS by PbgA coordinates the biosynthesis of lipid A by regulating the stability of LpxC, a key cytoplasmic biosynthetic enzyme10-12. In summary, we find that PbgA has an unexpected but essential role in the regulation of LPS biogenesis, presents a new structural basis for the selective recognition of lipids, and provides opportunities for future antibiotic discovery.


Asunto(s)
Membrana Celular/química , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/química , Escherichia coli/patogenicidad , Lipopolisacáridos/química , Lipopolisacáridos/metabolismo , Amidohidrolasas/química , Amidohidrolasas/metabolismo , Secuencias de Aminoácidos , Membrana Externa Bacteriana/química , Membrana Externa Bacteriana/metabolismo , Sitios de Unión , Membrana Celular/metabolismo , Estabilidad de Enzimas , Escherichia coli/citología , Escherichia coli/efectos de los fármacos , Genes Esenciales , Hidrolasas/química , Hidrolasas/metabolismo , Lípido A/química , Lípido A/metabolismo , Lipopolisacáridos/biosíntesis , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Modelos Moleculares , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , Periplasma/química , Periplasma/metabolismo , Unión Proteica , Virulencia
9.
Proc Natl Acad Sci U S A ; 120(15): e2213149120, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37027429

RESUMEN

Cryoelectron tomography directly visualizes heterogeneous macromolecular structures in their native and complex cellular environments. However, existing computer-assisted structure sorting approaches are low throughput or inherently limited due to their dependency on available templates and manual labels. Here, we introduce a high-throughput template-and-label-free deep learning approach, Deep Iterative Subtomogram Clustering Approach (DISCA), that automatically detects subsets of homogeneous structures by learning and modeling 3D structural features and their distributions. Evaluation on five experimental cryo-ET datasets shows that an unsupervised deep learning based method can detect diverse structures with a wide range of molecular sizes. This unsupervised detection paves the way for systematic unbiased recognition of macromolecular complexes in situ.


Asunto(s)
Tomografía con Microscopio Electrónico , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Análisis por Conglomerados , Estructura Molecular , Tomografía con Microscopio Electrónico/métodos , Sustancias Macromoleculares/química , Microscopía por Crioelectrón/métodos
10.
Proc Natl Acad Sci U S A ; 120(14): e2212387120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36996110

RESUMEN

The purinergic signaling molecule adenosine (Ado) modulates many physiological and pathological functions in the brain. However, the exact source of extracellular Ado remains controversial. Here, utilizing a newly optimized genetically encoded GPCR-Activation-Based Ado fluorescent sensor (GRABAdo), we discovered that the neuronal activity-induced extracellular Ado elevation is due to direct Ado release from somatodendritic compartments of neurons, rather than from the axonal terminals, in the hippocampus. Pharmacological and genetic manipulations reveal that the Ado release depends on equilibrative nucleoside transporters but not the conventional vesicular release mechanisms. Compared with the fast-vesicular glutamate release, the Ado release is slow (~40 s) and requires calcium influx through L-type calcium channels. Thus, this study reveals an activity-dependent second-to-minute local Ado release from the somatodendritic compartments of neurons, potentially serving modulatory functions as a retrograde signal.


Asunto(s)
Adenosina , Neuronas , Adenosina/farmacología , Proteínas de Transporte de Nucleósidos/genética , Transducción de Señal/fisiología , Factores de Intercambio de Guanina Nucleótido/metabolismo
11.
Proc Natl Acad Sci U S A ; 120(28): e2302226120, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399403

RESUMEN

Plant intracellular nucleotide-binding domain, leucine-rich repeat-containing receptors (NLRs) activate a robust immune response upon detection of pathogen effectors. How NLRs induce downstream immune defense genes remains poorly understood. The Mediator complex plays a central role in transducing signals from gene-specific transcription factors to the transcription machinery for gene transcription/activation. In this study, we demonstrate that MED10b and MED7 of the Mediator complex mediate jasmonate-dependent transcription repression, and coiled-coil NLRs (CNLs) in Solanaceae modulate MED10b/MED7 to activate immunity. Using the tomato CNL Sw-5b, which confers resistance to tospovirus, as a model, we found that the CC domain of Sw-5b directly interacts with MED10b. Knockout/down of MED10b and other subunits including MED7 of the middle module of Mediator activates plant defense against tospovirus. MED10b was found to directly interact with MED7, and MED7 directly interacts with JAZ proteins, which function as transcriptional repressors of jasmonic acid (JA) signaling. MED10b-MED7-JAZ together can strongly repress the expression of JA-responsive genes. The activated Sw-5b CC interferes with the interaction between MED10b and MED7, leading to the activation of JA-dependent defense signaling against tospovirus. Furthermore, we found that CC domains of various other CNLs including helper NLR NRCs from Solanaceae modulate MED10b/MED7 to activate defense against different pathogens. Together, our findings reveal that MED10b/MED7 serve as a previously unknown repressor of jasmonate-dependent transcription repression and are modulated by diverse CNLs in Solanaceae to activate the JA-specific defense pathways.


Asunto(s)
Proteínas de Arabidopsis , Inmunidad de la Planta , Inmunidad de la Planta/genética , Ciclopentanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Complejo Mediador/genética , Complejo Mediador/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
12.
Development ; 149(10)2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35575074

RESUMEN

Recent evidence has shown that presenilin enhancer 2 (Pen2; Psenen) plays an essential role in corticogenesis by regulating the switch of apical progenitors (APs) to basal progenitors (BPs). The hippocampus is a brain structure required for advanced functions, including spatial navigation, learning and memory. However, it remains unknown whether Pen2 is important for hippocampal morphogenesis. To address this question, we generated Pen2 conditional knockout (cKO) mice, in which Pen2 is inactivated in neural progenitor cells (NPCs) in the hippocampal primordium. We showed that Pen2 cKO mice exhibited hippocampal malformation and decreased population of NPCs in the neuroepithelium of the hippocampus. We found that deletion of Pen2 neither affected the proliferative capability of APs nor the switch of APs to BPs in the hippocampus, and that it caused enhanced transition of APs to neurons. We demonstrated that expression of the Notch1 intracellular domain (N1ICD) significantly increased the population of NPCs in the Pen2 cKO hippocampus. Collectively, this study uncovers a crucial role for Pen2 in the maintenance of NPCs during hippocampal development.


Asunto(s)
Hipocampo , Neuronas , Animales , Hipocampo/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neurogénesis/genética , Neuronas/metabolismo , Presenilinas/metabolismo
13.
Bioinformatics ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889274

RESUMEN

MOTIVATION: Deep learning models have achieved remarkable success in a wide range of natural-world tasks, such as vision, language, and speech recognition. These accomplishments are largely attributed to the availability of open-source large-scale datasets. More importantly, pre-trained foundational modellearnings exhibit a surprising degree of transferability to downstream tasks, enabling efficient learning even with limited training examples. However, the application of such natural-domain models to the domain of tiny Cryo-Electron Tomography (Cryo-ET) images has been a relatively unexplored frontier. This research is motivated by the intuition that 3D Cryo-ET voxel data can be conceptually viewed as a sequence of progressively evolving video frames. RESULTS: Leveraging the above insight, we propose a novel approach that involves the utilization of 3D models pre-trained on large-scale video datasets to enhance Cryo-ET subtomogram classification. Our experiments, conducted on both simulated and real Cryo-ET datasets, reveal compelling results. The use of video initialization not only demonstrates improvements in classification accuracy but also substantially reduces training costs. Further analyses provide additional evidence of the value of video initialization in enhancing subtomogram feature extraction. Additionally, we observe that video initialization yields similar positive effects when applied to medical 3D classification tasks, underscoring the potential of cross-domain knowledge transfer from video-based models to advance the state-of-the-art in a wide range of biological and medical data types. AVAILABILITY AND IMPLEMENTATION: https://github.com/xulabs/aitom.

14.
Nat Immunol ; 14(12): 1229-36, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24141388

RESUMEN

Type 2 innate lymphoid cells (ILC2 cells) participate in host defense against helminth parasites and in allergic inflammation. Given their functional relatedness to type 2 helper T cells (T(H)2 cells), we explored whether Gfi1 acts as a shared transcriptional determinant in ILC2 cells. Gfi1 promoted the development of ILC2 cells and controlled their responsiveness during infection with Nippostrongylus brasiliensis and protease allergen-induced lung inflammation. Gfi1 'preferentially' regulated the responsiveness of ILC2 cells to interleukin 33 (IL-33) by directly activating Il1rl1, which encodes the IL-33 receptor (ST2). Loss of Gfi1 in activated ILC2 cells resulted in impaired expression of the transcription factor GATA-3 and a dysregulated genome-wide effector state characterized by coexpression of IL-13 and IL-17. Our findings establish Gfi1 as a shared determinant that reciprocally regulates the type 2 and IL-17 effector states in cells of the innate and adaptive immune systems.


Asunto(s)
Proteínas de Unión al ADN/inmunología , Inmunidad Innata/inmunología , Células Th2/inmunología , Factores de Transcripción/inmunología , Transcriptoma/inmunología , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Células Cultivadas , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Citometría de Flujo , Factor de Transcripción GATA3/genética , Factor de Transcripción GATA3/inmunología , Factor de Transcripción GATA3/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1 , Interleucina-13/genética , Interleucina-13/inmunología , Interleucina-13/metabolismo , Interleucina-17/genética , Interleucina-17/inmunología , Interleucina-17/metabolismo , Interleucina-33 , Interleucinas/farmacología , Pulmón/inmunología , Pulmón/metabolismo , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos , Ratones Noqueados , Ratones Transgénicos , Nippostrongylus/inmunología , Nippostrongylus/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores de Interleucina/genética , Receptores de Interleucina/inmunología , Receptores de Interleucina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Infecciones por Strongylida/inmunología , Infecciones por Strongylida/parasitología , Células Th2/metabolismo , Células Th2/parasitología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma/genética
15.
Plant Physiol ; 194(4): 2533-2548, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38142233

RESUMEN

Aluminum-activated malate transporters (ALMTs) and slow anion channels (SLACs) are important in various physiological processes in plants, including stomatal regulation, nutrient uptake, and in response to abiotic stress such as aluminum toxicity. To understand their evolutionary history and functional divergence, we conducted phylogenetic and expression analyses of ALMTs and SLACs in green plants. Our findings from phylogenetic studies indicate that ALMTs and SLACs may have originated from green algae and red algae, respectively. The ALMTs of early land plants and charophytes formed a monophyletic clade consisting of three subgroups. A single duplication event of ALMTs was identified in vascular plants and subsequent duplications into six clades occurred in angiosperms, including an identified clade, 1-1. The ALMTs experienced gene number losses in clades 1-1 and 2-1 and expansions in clades 1-2 and 2-2b. Interestingly, the expansion of clade 1-2 was also associated with higher expression levels compared to genes in clades that experienced apparent loss. SLACs first diversified in bryophytes, followed by duplication in vascular plants, giving rise to three distinct clades (I, II, and III), and clade II potentially associated with stomatal control in seed plants. SLACs show losses in clades II and III without substantial expansion in clade I. Additionally, ALMT clade 2-2 and SLAC clade III contain genes specifically expressed in reproductive organs and roots in angiosperms, lycophytes, and mosses, indicating neofunctionalization. In summary, our study demonstrates the evolutionary complexity of ALMTs and SLACs, highlighting their crucial role in the adaptation and diversification of vascular plants.


Asunto(s)
Magnoliopsida , Proteínas de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Aluminio/metabolismo , Plantas/genética , Plantas/metabolismo , Evolución Biológica , Magnoliopsida/genética , Evolución Molecular
16.
Plant Cell ; 34(11): 4495-4515, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-35972376

RESUMEN

Cold tolerance at the booting (CTB) stage is a major factor limiting rice (Oryza sativa L.) productivity and geographical distribution. A few cold-tolerance genes have been identified, but they either need to be overexpressed to result in CTB or cause yield penalties, limiting their utility for breeding. Here, we characterize the function of the cold-induced transcription factor WRKY53 in rice. The wrky53 mutant displays increased CTB, as determined by higher seed setting. Low temperature is associated with lower gibberellin (GA) contents in anthers in the wild type but not in the wrky53 mutant, which accumulates slightly more GA in its anthers. WRKY53 directly binds to the promoters of GA biosynthesis genes and transcriptionally represses them in anthers. In addition, we uncover a possible mechanism by which GA regulates male fertility: SLENDER RICE1 (SLR1) interacts with and sequesters two critical transcription factors for tapetum development, UNDEVELOPED TAPETUM1 (UDT1), and TAPETUM DEGENERATION RETARDATION (TDR), and GA alleviates the sequestration by SLR1, thus allowing UDT1 and TDR to activate transcription. Finally, knocking out WRKY53 in diverse varieties increases cold tolerance without a yield penalty, leading to a higher yield in rice subjected to cold stress. Together, these findings provide a target for improving CTB in rice.


Asunto(s)
Oryza , Oryza/metabolismo , Giberelinas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genes de Plantas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
Int Immunol ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38955508

RESUMEN

Regulatory T cells (Tregs) ameliorate inflammatory bowel diseases. However, their plasticity is not completely understood. In this study using a mouse colitis model, Tregs and T helper 17 (Th17)-like Tregs were detected and sorted using flow cytometry, followed by transcriptome sequencing, real-time RT-PCR, and flow cytometry to analyze the mRNA profiles of these cells. Treg plasticity was evaluated by in vitro differentiation assays. The immunosuppressive activities of Tregs and Th17-like Tregs were assessed in an adoptive transfer assay. We found Tregs-derived Th17-like Tregs in inflamed colonic lamina propria (LP). LP Th17-like Tregs expressed higher Th17-related cytokines and lower immunosuppressive cytokines compared with LP Tregs. Notably, Tregs expressed higher Yes-associated protein 1 (YAP1) but lower transcriptional coactivator with PDZ­binding motif (TAZ) than Th17-like Tregs. Verteporfin-mediated inhibition of YAP1 activity enhanced Th17-like Treg generation, whereas IBS008739-induced TAZ activation did not affect Th17-like Treg generation. Besides, verteporfin enhanced while IBS008739 suppressed the differentiation of Th17-like Tregs into Th17 cells. Furthermore, YAP1 activated STAT5 signaling in Tregs, whereas YAP1 and TAZ activated STAT3 and STAT5 signaling in Th17-like Tregs. Compared with Tregs, Th17-like Tregs were less efficacious in ameliorating colitis. Therefore, YAP1 suppressed Treg differentiation into Th17-like Tregs. Both YAP1 and TAZ inhibited the differentiation of Th17-like Tregs into Th17 cells. Therefore, YAP1 and TAZ probably maintain the immunosuppressive activities of Tregs and Th17-like Tregs in colitis.

18.
PLoS Biol ; 20(1): e3001522, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35061665

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) affects approximately a quarter of the population worldwide, and persistent overnutrition is one of the major causes. However, the underlying molecular basis has not been fully elucidated, and no specific drug has been approved for this disease. Here, we identify a regulatory mechanism that reveals a novel function of Rab2A in the progression of NAFLD based on energy status and PPARγ. The mechanistic analysis shows that nutrition repletion suppresses the phosphorylation of AMPK-TBC1D1 signaling, augments the level of GTP-bound Rab2A, and then increases the protein stability of PPARγ, which ultimately promotes the hepatic accumulation of lipids in vitro and in vivo. Furthermore, we found that blocking the AMPK-TBC1D1 pathway in TBC1D1S231A-knock-in (KI) mice led to a markedly increased GTP-bound Rab2A and subsequent fatty liver in aged mice. Our studies also showed that inhibition of Rab2A expression alleviated hepatic lipid deposition in western diet-induced obesity (DIO) mice by reducing the protein level of PPARγ and the expression of PPARγ target genes. Our findings not only reveal a new molecular mechanism regulating the progression of NAFLD during persistent overnutrition but also have potential implications for drug discovery to combat this disease.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Proteínas de Unión al GTP rab/metabolismo , Envejecimiento , Animales , Regulación de la Expresión Génica , Técnicas de Sustitución del Gen , Células Hep G2 , Humanos , Metabolismo de los Lípidos/fisiología , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , Proteínas de Unión al GTP rab/genética
19.
Methods ; 222: 112-121, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38215898

RESUMEN

Design of molecules for candidate compound selection is one of the central challenges in drug discovery due to the complexity of chemical space and requirement of multi-parameter optimization. Here we present an application scenario-oriented platform (ID4Idea) for molecule generation in different scenarios of drug discovery. This platform utilizes both library or rule based and generative based algorithms (VAE, RNN, GAN, etc.), in combination with various AI learning types (pre-training, transfer learning, reinforcement learning, active learning, etc.) and input representations (1D SMILES, 2D graph, 3D shape, binding site, pharmacophore, etc.), to enable customized solutions for a given molecular design scenario. Besides the usual generation followed screening protocol, goal-directed molecule generation can also be conducted towards predefined goals, enhancing the efficiency of hit identification, lead finding, and lead optimization. We demonstrate the effectiveness of ID4Idea platform through case studies, showcasing customized solutions for different design tasks using various input information, such as binding pockets, pharmacophores, and compound representations. In addition, remaining challenges are discussed to unlock the full potential of AI models in drug discovery and pave the way for the development of novel therapeutics.


Asunto(s)
Diseño de Fármacos , Descubrimiento de Drogas , Sitios de Unión , Algoritmos , Biblioteca de Genes
20.
Cereb Cortex ; 34(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38652552

RESUMEN

The brain networks for the first (L1) and second (L2) languages are dynamically formed in the bilingual brain. This study delves into the neural mechanisms associated with logographic-logographic bilingualism, where both languages employ visually complex and conceptually rich logographic scripts. Using functional Magnetic Resonance Imaging, we examined the brain activity of Chinese-Japanese bilinguals and Japanese-Chinese bilinguals as they engaged in rhyming tasks with Chinese characters and Japanese Kanji. Results showed that Japanese-Chinese bilinguals processed both languages using common brain areas, demonstrating an assimilation pattern, whereas Chinese-Japanese bilinguals recruited additional neural regions in the left lateral prefrontal cortex for processing Japanese Kanji, reflecting their accommodation to the higher phonological complexity of L2. In addition, Japanese speakers relied more on the phonological processing route, while Chinese speakers favored visual form analysis for both languages, indicating differing neural strategy preferences between the 2 bilingual groups. Moreover, multivariate pattern analysis demonstrated that, despite the considerable neural overlap, each bilingual group formed distinguishable neural representations for each language. These findings highlight the brain's capacity for neural adaptability and specificity when processing complex logographic languages, enriching our understanding of the neural underpinnings supporting bilingual language processing.


Asunto(s)
Mapeo Encefálico , Encéfalo , Imagen por Resonancia Magnética , Multilingüismo , Humanos , Masculino , Femenino , Adulto Joven , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Adulto , Fonética , Lectura , Lenguaje , Japón
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