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1.
Nature ; 618(7967): 1072-1077, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37196676

RESUMEN

Plasma membrane rupture (PMR) in dying cells undergoing pyroptosis or apoptosis requires the cell-surface protein NINJ11. PMR releases pro-inflammatory cytoplasmic molecules, collectively called damage-associated molecular patterns (DAMPs), that activate immune cells. Therefore, inhibiting NINJ1 and PMR may limit the inflammation that is associated with excessive cell death. Here we describe an anti-NINJ1 monoclonal antibody that specifically targets mouse NINJ1 and blocks oligomerization of NINJ1, preventing PMR. Electron microscopy studies showed that this antibody prevents NINJ1 from forming oligomeric filaments. In mice, inhibition of NINJ1 or Ninj1 deficiency ameliorated hepatocellular PMR induced with TNF plus D-galactosamine, concanavalin A, Jo2 anti-Fas agonist antibody or ischaemia-reperfusion injury. Accordingly, serum levels of lactate dehydrogenase, the liver enzymes alanine aminotransaminase and aspartate aminotransferase, and the DAMPs interleukin 18 and HMGB1 were reduced. Moreover, in the liver ischaemia-reperfusion injury model, there was an attendant reduction in neutrophil infiltration. These data indicate that NINJ1 mediates PMR and inflammation in diseases driven by aberrant hepatocellular death.


Asunto(s)
Anticuerpos Monoclonales , Membrana Celular , Inflamación , Hígado , Factores de Crecimiento Nervioso , Daño por Reperfusión , Animales , Ratones , Alanina Transaminasa , Alarminas , Anticuerpos Monoclonales/inmunología , Aspartato Aminotransferasas , Moléculas de Adhesión Celular Neuronal/antagonistas & inhibidores , Moléculas de Adhesión Celular Neuronal/deficiencia , Moléculas de Adhesión Celular Neuronal/inmunología , Moléculas de Adhesión Celular Neuronal/ultraestructura , Muerte Celular , Membrana Celular/patología , Membrana Celular/ultraestructura , Concanavalina A , Galactosamina , Hepatocitos/patología , Hepatocitos/ultraestructura , Inflamación/patología , Lactato Deshidrogenasas , Hígado/patología , Microscopía Electrónica , Factores de Crecimiento Nervioso/antagonistas & inhibidores , Factores de Crecimiento Nervioso/deficiencia , Factores de Crecimiento Nervioso/inmunología , Factores de Crecimiento Nervioso/ultraestructura , Infiltración Neutrófila , Daño por Reperfusión/patología
2.
Nature ; 612(7939): 246-251, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36385532

RESUMEN

A step towards the next generation of high-capacity, noise-resilient communication and computing technologies is a substantial increase in the dimensionality of information space and the synthesis of superposition states on an N-dimensional (N > 2) Hilbert space featuring exotic group symmetries. Despite the rapid development of photonic devices and systems, on-chip information technologies are mostly limited to two-level systems owing to the lack of sufficient reconfigurability to satisfy the stringent requirement for 2(N - 1) degrees of freedom, intrinsically associated with the increase of synthetic dimensionalities. Even with extensive efforts dedicated to recently emerged vector lasers and microcavities for the expansion of dimensionalities1-10, it still remains a challenge to actively tune the diversified, high-dimensional superposition states of light on demand. Here we demonstrate a hyperdimensional, spin-orbit microlaser for chip-scale flexible generation and manipulation of arbitrary four-level states. Two microcavities coupled through a non-Hermitian synthetic gauge field are designed to emit spin-orbit-coupled states of light with six degrees of freedom. The vectorial state of the emitted laser beam in free space can be mapped on a Bloch hypersphere defining an SU(4) symmetry, demonstrating dynamical generation and reconfiguration of high-dimensional superposition states with high fidelity.


Asunto(s)
Comunicación , Tecnología de la Información , Fotones , Tecnología
3.
EMBO J ; 42(13): e112998, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37211868

RESUMEN

Brassinosteroids (BRs) are important plant hormones involved in many aspects of development. Here, we show that BRASSINOSTEROID SIGNALING KINASEs (BSKs), key components of the BR pathway, are precisely controlled via de-S-acylation mediated by the defense hormone salicylic acid (SA). Most Arabidopsis BSK members are substrates of S-acylation, a reversible protein lipidation that is essential for their membrane localization and physiological function. We establish that SA interferes with the plasma membrane localization and function of BSKs by decreasing their S-acylation levels, identifying ABAPT11 (ALPHA/BETA HYDROLASE DOMAIN-CONTAINING PROTEIN 17-LIKE ACYL PROTEIN THIOESTERASE 11) as an enzyme whose expression is quickly induced by SA. ABAPT11 de-S-acylates most BSK family members, thus integrating BR and SA signaling for the control of plant development. In summary, we show that BSK-mediated BR signaling is regulated by SA-induced protein de-S-acylation, which improves our understanding of the function of protein modifications in plant hormone cross talk.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Brasinoesteroides/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ácido Salicílico/metabolismo , Arabidopsis/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Acilación , Regulación de la Expresión Génica de las Plantas
4.
Plant Cell ; 36(6): 2375-2392, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38470570

RESUMEN

Homeodomain (HD) proteins regulate embryogenesis in animals such as the fruit fly (Drosophila melanogaster), often in a concentration-dependent manner. HD-leucine zipper (Zip) IV family genes are unique to plants and often function in the L1 epidermal cell layer. However, our understanding of the roles of HD-Zip IV family genes in plant morphogenesis is limited. In this study, we investigated the morphogenesis of tomato (Solanum lycopersicum) multicellular trichomes, a type of micro-organ in plants. We found that a gradient of the HD-Zip IV regulator Woolly (Wo) coordinates spatially polarized cell division and cell expansion in multicellular trichomes. Moreover, we identified a TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATING CELL NUCLEAR ANTIGEN BINDING FACTOR (TCP) transcription factor-encoding gene, SlBRANCHED2a (SlBRC2a), as a key downstream target of Wo that regulates the transition from cell division to cell expansion. High levels of Wo promote cell division in apical trichome cells, whereas in basal trichome cells, Wo mediates a negative feedback loop with SlBRC2a that forces basal cells to enter endoreduplication. The restricted high and low activities of Wo pattern the morphogenesis of tomato multicellular trichomes. These findings provide insights into the functions of HD-Zip IV genes during plant morphogenesis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Morfogénesis , Proteínas de Plantas , Solanum lycopersicum , Tricomas , Solanum lycopersicum/genética , Solanum lycopersicum/crecimiento & desarrollo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/citología , Tricomas/crecimiento & desarrollo , Tricomas/genética , Tricomas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Morfogénesis/genética , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , División Celular
5.
Plant Cell ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404780

RESUMEN

Herbivore-induced wounding can elicit a defense response in plants. However, whether plants possess a surveillance system capable of detecting herbivore threats and initiating preparatory defenses before wounding occurs remains unclear. In this study, we reveal that tomato (Solanum lycopersicum) trichomes can detect and respond to the mechanical stimuli generated by herbivores. Mechanical stimuli are preferentially perceived by long trichomes, and this mechanosensation is transduced via intra-trichome communication. This communication presumably involves calcium waves, and the transduced signals activate the jasmonic acid (JA) signaling pathway in short glandular trichomes, resulting in the upregulation of the Woolly (Wo)-SlMYC1 regulatory module for terpene biosynthesis. This induced defense mechanism provides plants with an early warning system against the threat of herbivore invasion. Our findings represent a perspective on the role of multicellular trichomes in plant defense and the underlying intra-trichome communication.

6.
Nature ; 589(7843): 586-590, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33299183

RESUMEN

Legumes, unlike other plants, have the ability to establish symbiosis with nitrogen-fixing rhizobia. It has been theorized that a unique property of legume root cortical cells enabled the initial establishment of rhizobial symbiosis1-3. Here we show that a SHORTROOT-SCARECROW (SHR-SCR) stem cell program in cortical cells of the legume Medicago truncatula specifies their distinct fate. Regulatory elements drive the cortical expression of SCR, and stele-expressed SHR protein accumulates in cortical cells of M. truncatula but not Arabidopsis thaliana. The cortical SHR-SCR network is conserved across legume species, responds to rhizobial signals, and initiates legume-specific cortical cell division for de novo nodule organogenesis and accommodation of rhizobia. Ectopic activation of SHR and SCR in legumes is sufficient to induce root cortical cell division. Our work suggests that acquisition of the cortical SHR-SCR module enabled cell division coupled to rhizobial infection in legumes. We propose that this event was central to the evolution of rhizobial endosymbiosis.


Asunto(s)
Diferenciación Celular , Linaje de la Célula , Medicago truncatula/citología , Medicago truncatula/metabolismo , Proteínas de Plantas/metabolismo , Nodulación de la Raíz de la Planta , Arabidopsis/citología , Arabidopsis/metabolismo , División Celular , Citocininas/metabolismo , Evolución Molecular , Medicago truncatula/embriología , Proteínas de Plantas/genética , Raíces de Plantas/citología , Raíces de Plantas/metabolismo , Regiones Promotoras Genéticas/genética , Rhizobium/metabolismo , Transducción de Señal , Simbiosis/genética
7.
Proc Natl Acad Sci U S A ; 121(20): e2322625121, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38709915

RESUMEN

Soft robots often draw inspiration from nature to navigate different environments. Although the inching motion and crawling motion of caterpillars have been widely studied in the design of soft robots, the steering motion with local bending control remains challenging. To address this challenge, we explore modular origami units which constitute building blocks for mimicking the segmented caterpillar body. Based on this concept, we report a modular soft Kresling origami crawling robot enabled by electrothermal actuation. A compact and lightweight Kresling structure is designed, fabricated, and characterized with integrated thermal bimorph actuators consisting of liquid crystal elastomer and polyimide layers. With the modular design and reprogrammable actuation, a multiunit caterpillar-inspired soft robot composed of both active units and passive units is developed for bidirectional locomotion and steering locomotion with precise curvature control. We demonstrate the modular design of the Kresling origami robot with an active robotic module picking up cargo and assembling with another robotic module to achieve a steering function. The concept of modular soft robots can provide insight into future soft robots that can grow, repair, and enhance functionality.

8.
Proc Natl Acad Sci U S A ; 120(42): e2308496120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812720

RESUMEN

Human diseases involve metabolic alterations. Metabolomic profiles have served as a vital biomarker for the early identification of high-risk individuals and disease prevention. However, current approaches can only characterize individual key metabolites, without taking into account the reality that complex diseases are multifactorial, dynamic, heterogeneous, and interdependent. Here, we leverage a statistical physics model to combine all metabolites into bidirectional, signed, and weighted interaction networks and trace how the flow of information from one metabolite to the next causes changes in health state. Viewing a disease outcome as the consequence of complex interactions among its interconnected components (metabolites), we integrate concepts from ecosystem theory and evolutionary game theory to model how the health state-dependent alteration of a metabolite is shaped by its intrinsic properties and through extrinsic influences from its conspecifics. We code intrinsic contributions as nodes and extrinsic contributions as edges into quantitative networks and implement GLMY homology theory to analyze and interpret the topological change of health state from symbiosis to dysbiosis and vice versa. The application of this model to real data allows us to identify several hub metabolites and their interaction webs, which play a part in the formation of inflammatory bowel diseases. The findings by our model could provide important information on drug design to treat these diseases and beyond.


Asunto(s)
Ecosistema , Metabolómica , Humanos , Modelos Estadísticos , Biomarcadores/metabolismo , Física
9.
Proc Natl Acad Sci U S A ; 120(45): e2304848120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37903254

RESUMEN

Ecological divergence without geographic isolation, as an early speciation process that may lead finally to reproductive isolation through natural selection, remains a captivating topic in evolutionary biology. However, the pattern of genetic divergence underlying this process across the genome may vary between species and mating systems. Here, we present evidence that Brachypodium stacei, an annual and highly selfing grass model species, has undergone sympatric ecological divergence without geographic isolation. Genomic, transcriptomic, and metabolomic analyses together with lab experiments mimicking the two opposite environmental conditions suggest that diploid B. stacei populations have diverged sympatrically in two slopes characterized by distinct biomes at Evolution Canyon I (ECI), Mount Carmel, Israel. Despite ongoing gene flow, primarily facilitated by seed dispersal, the level of gene flow has progressively decreased over time. This local adaptation involves the scattered divergence of many unlinked loci across the total genome that include both coding genes and noncoding regions. Additionally, we have identified significant differential expressions of genes related to the ABA signaling pathway and contrasting metabolome composition between the arid- vs. forest-adapted B. stacei populations in ECI. These results suggest that multiple small loci involved in environmental responses act additively to account for ecological adaptations by this selfing species in contrasting environments.


Asunto(s)
Brachypodium , Brachypodium/genética , Diploidia , Aislamiento Reproductivo , Ecosistema , Genoma de Planta/genética , Especiación Genética
10.
Am J Pathol ; 194(7): 1248-1261, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38599461

RESUMEN

Mucosal-associated invariant T (MAIT) cells are essential in defending against infection. Sepsis is a systemic inflammatory response to infection and a leading cause of death. The relationship between the overall competency of the host immune response and disease severity is not fully elucidated. This study identified a higher proportion of circulating MAIT17 with expression of IL-17A and retinoic acid receptor-related orphan receptor γt in patients with sepsis. The proportion of MAIT17 was correlated with the severity of sepsis. Single-cell RNA-sequencing analysis revealed an enhanced expression of lactate dehydrogenase A (LDHA) in MAIT17 in patients with sepsis. Cell-culture experiments demonstrated that phosphoinositide 3-kinase-LDHA signaling was required for retinoic acid receptor-related orphan receptor γt expression in MAIT17. Finally, the elevated levels of plasma IL-18 promoted the differentiation of circulating MAIT17 cells in sepsis. In summary, this study reveals a new role of circulating MAIT17 in promoting sepsis severity and suggests the phosphoinositide 3-kinase-LDHA signaling as a driving force in MAIT17 responses.


Asunto(s)
Diferenciación Celular , Células T Invariantes Asociadas a Mucosa , Sepsis , Humanos , Sepsis/inmunología , Sepsis/patología , Sepsis/sangre , Células T Invariantes Asociadas a Mucosa/inmunología , Células T Invariantes Asociadas a Mucosa/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Anciano , Interleucina-17/metabolismo , Interleucina-17/sangre , Transducción de Señal , Fosfatidilinositol 3-Quinasas/metabolismo
11.
Nat Immunol ; 14(6): 584-92, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23624556

RESUMEN

Interleukin 17 (IL-17)-committed γδ T cells (γδT17 cells) participate in many immune responses, but their developmental requirements and subset specific functions remain poorly understood. Here we report that a commonly used CD45.1(+) congenic C57BL/6 mouse substrain is characterized by selective deficiency in Vγ4(+) γδT17 cells. This trait was due to a spontaneous mutation in the gene encoding the transcription factor Sox13 that caused an intrinsic defect in development of those cells in the neonatal thymus. The γδT17 cells migrated from skin to lymph nodes at low rates. In a model of psoriasis-like dermatitis, the Vγ4(+) γδT17 cell subset expanded considerably in lymph nodes and homed to inflamed skin. Sox13-mutant mice were protected from psoriasis-like skin changes, which identified a role for Sox13-dependent γδT17 cells in this inflammatory condition.


Asunto(s)
Autoantígenos/inmunología , Dermatitis/inmunología , Interleucina-17/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Animales Recién Nacidos , Autoantígenos/genética , Autoantígenos/metabolismo , Células Cultivadas , Dermatitis/genética , Dermatitis/metabolismo , Citometría de Flujo , Interleucina-17/genética , Interleucina-17/metabolismo , Antígenos Comunes de Leucocito/genética , Antígenos Comunes de Leucocito/inmunología , Antígenos Comunes de Leucocito/metabolismo , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Ratones , Ratones Congénicos , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Endogámicos NOD , Ratones Noqueados , Mutación , Psoriasis/genética , Psoriasis/inmunología , Psoriasis/metabolismo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Subgrupos de Linfocitos T/metabolismo , Timo/inmunología , Timo/metabolismo , Timo/patología
12.
Plant Cell ; 34(10): 4045-4065, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-35863053

RESUMEN

Forming mutualistic symbioses with arbuscular mycorrhizae (AMs) improves the acquisition of mineral nutrients for most terrestrial plants. However, the formation of AM symbiosis usually occurs under phosphate (Pi)-deficient conditions. Here, we identify SlSPX1 (SYG1 (suppressor of yeast GPA1)/Pho81(phosphate 81)/XPR1 (xenotropic and polytropic retrovirus receptor 1) as the major repressor of the AM symbiosis in tomato (Solanum lycopersicum) under phosphate-replete conditions. Loss of SlSPX1 function promotes direct Pi uptake and enhances AM colonization under phosphate-replete conditions. We determine that SlSPX1 integrates Pi signaling and AM symbiosis by directly interacting with a set of arbuscule-induced SlPHR proteins (SlPHR1, SlPHR4, SlPHR10, SlPHR11, and SlPHR12). The association with SlSPX1 represses the ability of SlPHR proteins to activate AM marker genes required for the arbuscular mycorrhizal symbiosis. SlPHR proteins exhibit functional redundancy, and no defective AM symbiosis was detected in the single mutant of SlPHR proteins. However, silencing SlPHR4 in the Slphr1 mutant background led to reduced AM colonization. Therefore, our results support the conclusion that SlSPX1-SlPHRs form a Pi-sensing module to coordinate the AM symbiosis under different Pi-availability conditions.


Asunto(s)
Micorrizas , Solanum lycopersicum , Regulación de la Expresión Génica de las Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Minerales/metabolismo , Micorrizas/fisiología , Fosfatos/metabolismo , Raíces de Plantas/metabolismo , Simbiosis/fisiología
13.
Nature ; 572(7770): 497-501, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31367036

RESUMEN

Layered antiferromagnetism is the spatial arrangement of ferromagnetic layers with antiferromagnetic interlayer coupling. The van der Waals magnet chromium triiodide (CrI3) has been shown to be a layered antiferromagnetic insulator in its few-layer form1, opening up opportunities for various functionalities2-7 in electronic and optical devices. Here we report an emergent nonreciprocal second-order nonlinear optical effect in bilayer CrI3. The observed second-harmonic generation (SHG; a nonlinear optical process that converts two photons of the same frequency into one photon of twice the fundamental frequency) is several orders of magnitude larger than known magnetization-induced SHG8-11 and comparable to the SHG of the best (in terms of nonlinear susceptibility) two-dimensional nonlinear optical materials studied so far12,13 (for example, molybdenum disulfide). We show that although the parent lattice of bilayer CrI3 is centrosymmetric, and thus does not contribute to the SHG signal, the observed giant nonreciprocal SHG originates only from the layered antiferromagnetic order, which breaks both the spatial-inversion symmetry and the time-reversal symmetry. Furthermore, polarization-resolved measurements reveal underlying C2h crystallographic symmetry-and thus monoclinic stacking order-in bilayer CrI3, providing key structural information for the microscopic origin of layered antiferromagnetism14-18. Our results indicate that SHG is a highly sensitive probe of subtle magnetic orders and open up possibilities for the use of two-dimensional magnets in nonlinear and nonreciprocal optical devices.

14.
Nature ; 572(7767): 106-111, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31367028

RESUMEN

There are two general approaches to developing artificial general intelligence (AGI)1: computer-science-oriented and neuroscience-oriented. Because of the fundamental differences in their formulations and coding schemes, these two approaches rely on distinct and incompatible platforms2-8, retarding the development of AGI. A general platform that could support the prevailing computer-science-based artificial neural networks as well as neuroscience-inspired models and algorithms is highly desirable. Here we present the Tianjic chip, which integrates the two approaches to provide a hybrid, synergistic platform. The Tianjic chip adopts a many-core architecture, reconfigurable building blocks and a streamlined dataflow with hybrid coding schemes, and can not only accommodate computer-science-based machine-learning algorithms, but also easily implement brain-inspired circuits and several coding schemes. Using just one chip, we demonstrate the simultaneous processing of versatile algorithms and models in an unmanned bicycle system, realizing real-time object detection, tracking, voice control, obstacle avoidance and balance control. Our study is expected to stimulate AGI development by paving the way to more generalized hardware platforms.

15.
Cereb Cortex ; 34(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39191664

RESUMEN

Calcium ions (Ca2+) play crucial roles in almost every cellular process, making the detection of changes in intracellular Ca2+ essential to understanding cell function. The fluorescence indicator method has garnered widespread application due to its exceptional sensitivity, rapid analysis, cost-effectiveness, and user-friendly nature. It has successfully delineated the spatial and temporal dynamics of Ca2+ signaling across diverse cell types. However, it is vital to understand that different indicators have varying levels of accuracy, sensitivity, and stability, making choosing the right inspection method crucial. As optical detection technologies advance, they continually broaden the horizons of scientific inquiry. This primer offers a systematic synthesis of the current fluorescence indicators and optical imaging modalities utilized for the detection of intracellular Ca2+. It elucidates their practical applications and inherent limitations, serving as an essential reference for researchers seeking to identify the most suitable detection methodologies for their calcium-centric investigations.


Asunto(s)
Calcio , Colorantes Fluorescentes , Imagen Óptica , Calcio/metabolismo , Calcio/análisis , Humanos , Imagen Óptica/métodos , Animales , Señalización del Calcio/fisiología
16.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35022232

RESUMEN

Nitrogen fixation in soybean takes place in root nodules that arise from de novo cell divisions in the root cortex. Although several early nodulin genes have been identified, the mechanism behind the stimulation of cortical cell division during nodulation has not been fully resolved. Here we provide evidence that two paralogs of soybean SHORT-ROOT (GmSHR) play vital roles in soybean nodulation. Expression of GmSHR4 and GmSHR5 (GmSHR4/5) is induced in cortical cells at the beginning of nodulation, when the first cell divisions occur. The expression level of GmSHR4/5 is positively associated with cortical cell division and nodulation. Knockdown of GmSHR5 inhibits cell division in outer cortical layers during nodulation. Knockdown of both paralogs disrupts the cell division throughout the cortex, resulting in poorly organized nodule primordia with delayed vascular tissue formation. GmSHR4/5 function by enhancing cytokinin signaling and activating early nodulin genes. Interestingly, D-type cyclins act downstream of GmSHR4/5, and GmSHR4/5 form a feedforward loop regulating D-type cyclins. Overexpression of D-type cyclins in soybean roots also enhanced nodulation. Collectively, we conclude that the GmSHR4/5-mediated pathway represents a vital module that triggers cytokinin signaling and activates D-type cyclins during nodulation in soybean.


Asunto(s)
Ciclinas/metabolismo , Glycine max/metabolismo , Glycine max/fisiología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Nodulación de la Raíz de la Planta/fisiología , Nódulos de las Raíces de las Plantas/fisiología , Homología de Secuencia de Aminoácido , División Celular , Citocininas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de Plantas/genética , Transducción de Señal
17.
J Neurosci ; 43(11): 1859-1870, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36725322

RESUMEN

Age-related decline in visual functions is a prevalent health problem among elderly people, and no effective therapies are available up-to-date. Axon degeneration and myelin loss in optic nerves (ONs) are age-dependent and become evident in middle-aged (13-18 months) and old (20-22 months) mice of either sex compared with adult mice (3-8 months), accompanied by functional deficits. Oligodendrocyte (OL) turnover is actively going on in adult ONs. However, the longitudinal change and functional significance of OL turnover in aging ONs remain largely unknown. Here, using cell-lineage labeling and tracing, we reported that oligodendrogenesis displayed an age-dependent decrease in aging ONs. To understand whether active OL turnover is required for maintaining axons and visual function, we conditionally deleted the transcription factor Olig2 in the oligodendrocyte precursor cells of young mice. Genetically dampening OL turnover by Olig2 ablation resulted in accelerated axon loss and retinal degeneration, and subsequently impaired ON signal transmission, suggesting that OL turnover is an important mechanism to sustain axon survival and visual function. To test whether enhancing oligodendrogenesis can prevent age-related visual deficits, 12-month-old mice were treated with clemastine, a pro-myelination drug, or induced deletion of the muscarinic receptor 1 in oligodendrocyte precursor cells. The clemastine treatment or muscarinic receptor 1 deletion significantly increased new OL generation in the aged ONs and consequently preserved visual function and retinal integrity. Together, our data indicate that dynamic OL turnover in ONs is required for axon survival and visual function, and enhancing new OL generation represents a potential approach to reversing age-related declines of visual function.SIGNIFICANCE STATEMENT Oligodendrocyte (OL) turnover has been reported in adult optic nerves (ONs), but the longitudinal change and functional significance of OL turnover during aging remain largely unknown. Using cell-lineage tracing and oligodendroglia-specific manipulation, this study reported that OL generation was active in adult ONs and the efficiency decreased in an age-dependent manner. Genetically dampening OL generation by Olig2 ablation resulted in significant axon loss and retinal degeneration, along with delayed visual signal transmission. Conversely, pro-myelination approaches significantly increased new myelin generation in aging ONs, and consequently preserved retinal integrity and visual function. Our findings indicate that promoting OL generation might be a promising strategy to preserve visual function from age-related decline.


Asunto(s)
Clemastina , Degeneración Retiniana , Ratones , Animales , Clemastina/farmacología , Oligodendroglía/fisiología , Vaina de Mielina/fisiología , Nervio Óptico , Axones , Diferenciación Celular/fisiología
18.
Plant J ; 113(5): 969-985, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36587293

RESUMEN

Folate (vitamin B9) is important for plant root development, but the mechanism is largely unknown. Here we characterized a root defective mutant, folb2, in Arabidopsis, which has severe developmental defects in the primary root. The root apical meristem of the folb2 mutant is impaired, and adventitious roots are frequently found at the root-hypocotyl junction. Positional cloning revealed that a 61-bp deletion is present in the predicted junction region of the promoter and the 5' untranslated region of AtFolB2, a gene encoding a dihydroneopterin aldolase that functions in folate biosynthesis. This mutation leads to a significant reduction in the transcript level of AtFolB2. Liquid chromatography-mass spectrometry analysis showed that the contents of the selected folate compounds were decreased in folb2. Arabidopsis AtFolB2 knockdown lines phenocopy the folb2 mutant. On the other hand, the application of exogenous 5-formyltetrahydrofolic acid could rescue the root phenotype of folb2, indicating that the root phenotype is indeed related to the folate level. Further analysis revealed that folate could promote rootward auxin transport through auxin transporters and that folate may affect particular auxin/indole-3-acetic acid proteins and auxin response factors. Our findings provide new insights into the important role of folic acid in shaping root structure.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Raíces de Plantas/metabolismo , Meristema/genética , Ácidos Indolacéticos/metabolismo , Regulación de la Expresión Génica de las Plantas , Mutación
19.
Mol Plant Microbe Interact ; 37(4): 407-415, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38171376

RESUMEN

Mitochondria are highly dynamic organelles that constantly change their morphology to adapt to the cellular environment through fission and fusion, which is critical for a cell to maintain normal cellular functions. Despite the significance of this process in the development and pathogenicity of the rice blast fungus Magnaporthe oryzae, the underlying mechanism remains largely elusive. Here, we identified and characterized a mitochondrial outer membrane translocase, MoTom20, in M. oryzae. Targeted gene deletion revealed that MoTom20 plays an important role in vegetative growth, conidiogenesis, penetration, and infectious growth of M. oryzae. The growth rate, conidial production, appressorium turgor, and pathogenicity are decreased in the ΔMotom20 mutant compared with the wild-type and complemented strains. Further analysis revealed that MoTom20 localizes in mitochondrion and plays a key role in regulating mitochondrial fission and fusion balance, which is critical for infectious growth. Finally, we found that MoTom20 is involved in fatty-acid utilization, and its yeast homolog ScTom20 is able to rescue the defects of ΔMotom20 in mitochondrial morphology and pathogenicity. Overall, our data demonstrate that MoTom20 is a key regulator for mitochondrial morphology maintenance, which is important for infectious growth of the rice blast fungus M. oryzae. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Proteínas Fúngicas , Mitocondrias , Oryza , Enfermedades de las Plantas , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Mitocondrias/metabolismo , Esporas Fúngicas/crecimiento & desarrollo , Ascomicetos/genética , Ascomicetos/patogenicidad , Regulación Fúngica de la Expresión Génica , Membranas Mitocondriales/metabolismo , Virulencia , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Dinámicas Mitocondriales , Eliminación de Gen
20.
BMC Genomics ; 25(1): 120, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280985

RESUMEN

To comprehensively understand the characteristics of the GH3 gene family in tea plants (Camellia sinensis), we identified 17 CsGH3 genes and analyzed their physicochemical properties, phylogenetic relationships, gene structures, promoters, and expression patterns in different tissues. The study showed that the 17 CsGH3 genes are distributed on 9 chromosomes, and based on evolutionary analysis, the CsGH3 members were divided into three subgroups. Gene duplication analysis revealed that segmental duplications have a significant impact on the amplification of CsGH3 genes. In addition, we identified and classified cis-elements in the CsGH3 gene promoters and detected elements related to plant hormone responses and non-biotic stress responses. Through expression pattern analysis, we observed tissue-specific expression of CsGH3.3 and CsGH3.10 in flower buds and roots. Moreover, based on predictive analysis of upstream regulatory transcription factors of CsGH3, we identified the potential transcriptional regulatory role of gibberellin response factor CsDELLA in CsGH3.14 and CsGH3.15. In this study, we found that CsGH3 genes are involved in a wide range of activities, such as growth and development, stress response, and transcription. This is the first report on CsGH3 genes and their potential roles in tea plants. In conclusion, these results provide a theoretical basis for elucidating the role of GH3 genes in the development of perennial woody plants and offer new insights into the synergistic effects of multiple hormones on plant growth and development in tea plants.


Asunto(s)
Camellia sinensis , Camellia sinensis/metabolismo , Filogenia , Reguladores del Crecimiento de las Plantas/farmacología , Regiones Promotoras Genéticas , , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo
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