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1.
Nat Immunol ; 25(6): 969-980, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38831104

RESUMEN

Rare genetic variants in toll-like receptor 7 (TLR7) are known to cause lupus in humans and mice. UNC93B1 is a transmembrane protein that regulates TLR7 localization into endosomes. In the present study, we identify two new variants in UNC93B1 (T314A, located proximally to the TLR7 transmembrane domain, and V117L) in a cohort of east Asian patients with childhood-onset systemic lupus erythematosus. The V117L variant was associated with increased expression of type I interferons and NF-κB-dependent cytokines in patient plasma and immortalized B cells. THP-1 cells expressing the variant UNC93B1 alleles exhibited exaggerated responses to stimulation of TLR7/-8, but not TLR3 or TLR9, which could be inhibited by targeting the downstream signaling molecules, IRAK1/-4. Heterozygous mice expressing the orthologous Unc93b1V117L variant developed a spontaneous lupus-like disease that was more severe in homozygotes and again hyperresponsive to TLR7 stimulation. Together, this work formally identifies genetic variants in UNC93B1 that can predispose to childhood-onset systemic lupus erythematosus.


Asunto(s)
Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico , Receptor Toll-Like 7 , Lupus Eritematoso Sistémico/genética , Humanos , Animales , Receptor Toll-Like 7/genética , Receptor Toll-Like 7/metabolismo , Ratones , Niño , Femenino , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Masculino , Edad de Inicio , Variación Genética , FN-kappa B/metabolismo , Linfocitos B/inmunología , Linfocitos B/metabolismo , Adolescente , Células THP-1 , Interferón Tipo I/metabolismo
2.
Cell ; 184(12): 3178-3191.e18, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-34022140

RESUMEN

Gasdermin B (GSDMB) belongs to a large family of pore-forming cytolysins that execute inflammatory cell death programs. While genetic studies have linked GSDMB polymorphisms to human disease, its function in the immunological response to pathogens remains poorly understood. Here, we report a dynamic host-pathogen conflict between GSDMB and the IpaH7.8 effector protein secreted by enteroinvasive Shigella flexneri. We show that IpaH7.8 ubiquitinates and targets GSDMB for 26S proteasome destruction. This virulence strategy protects Shigella from the bacteriocidic activity of natural killer cells by suppressing granzyme-A-mediated activation of GSDMB. In contrast to the canonical function of most gasdermin family members, GSDMB does not inhibit Shigella by lysing host cells. Rather, it exhibits direct microbiocidal activity through recognition of phospholipids found on Gram-negative bacterial membranes. These findings place GSDMB as a central executioner of intracellular bacterial killing and reveal a mechanism employed by pathogens to counteract this host defense system.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Interacciones Huésped-Patógeno , Células Asesinas Naturales/inmunología , Proteínas de Neoplasias/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Shigella flexneri/fisiología , Ubiquitinación , Animales , Proteínas Bacterianas/metabolismo , Cardiolipinas/metabolismo , Línea Celular , Membrana Celular/metabolismo , Femenino , Granzimas/metabolismo , Humanos , Lípido A/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Viabilidad Microbiana , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica , Proteolisis , Especificidad por Sustrato
3.
Cell ; 183(7): 1867-1883.e26, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33248023

RESUMEN

Biliary atresia (BA) is a severe cholangiopathy that leads to liver failure in infants, but its pathogenesis remains to be fully characterized. By single-cell RNA profiling, we observed macrophage hypo-inflammation, Kupffer cell scavenger function defects, cytotoxic T cell expansion, and deficiency of CX3CR1+effector T and natural killer (NK) cells in infants with BA. More importantly, we discovered that hepatic B cell lymphopoiesis did not cease after birth and that tolerance defects contributed to immunoglobulin G (IgG)-autoantibody accumulation in BA. In a rhesus-rotavirus induced BA model, depleting B cells or blocking antigen presentation ameliorated liver damage. In a pilot clinical study, we demonstrated that rituximab was effective in depleting hepatic B cells and restoring the functions of macrophages, Kupffer cells, and T cells to levels comparable to those of control subjects. In summary, our comprehensive immune profiling in infants with BA had educed that B-cell-modifying therapies may alleviate liver pathology.


Asunto(s)
Atresia Biliar/inmunología , Atresia Biliar/terapia , Hígado/inmunología , Animales , Antígenos CD20/metabolismo , Linfocitos B/inmunología , Atresia Biliar/sangre , Atresia Biliar/tratamiento farmacológico , Biopsia , Receptor 1 de Quimiocinas CX3C/metabolismo , Muerte Celular , Línea Celular , Proliferación Celular , Transdiferenciación Celular , Niño , Preescolar , Estudios de Cohortes , Citotoxicidad Inmunológica , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunoglobulina G/metabolismo , Lactante , Inflamación/patología , Células Asesinas Naturales/inmunología , Macrófagos del Hígado/patología , Hígado/patología , Cirrosis Hepática/sangre , Cirrosis Hepática/complicaciones , Cirrosis Hepática/inmunología , Cirrosis Hepática/patología , Depleción Linfocítica , Linfopoyesis , Masculino , Ratones Endogámicos BALB C , Fagocitosis , ARN/metabolismo , Rituximab/administración & dosificación , Rituximab/farmacología , Rituximab/uso terapéutico , Rotavirus/fisiología , Análisis de la Célula Individual , Células TH1/inmunología , Células Th17/inmunología
4.
Mol Cell ; 83(11): 1887-1902.e8, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37244254

RESUMEN

Interleukin-1ß (IL-1ß) is a key protein in inflammation and contributes to tumor progression. However, the role of IL-1ß in cancer is ambiguous or even contradictory. Here, we found that upon IL-1ß stimulation, nicotinamide nucleotide transhydrogenase (NNT) in cancer cells is acetylated at lysine (K) 1042 (NNT K1042ac) and thereby induces the mitochondrial translocation of p300/CBP-associated factor (PCAF). This acetylation enhances NNT activity by increasing the binding affinity of NNT for NADP+ and therefore boosts NADPH production, which subsequently sustains sufficient iron-sulfur cluster maintenance and protects tumor cells from ferroptosis. Abrogating NNT K1042ac dramatically attenuates IL-1ß-promoted tumor immune evasion and synergizes with PD-1 blockade. In addition, NNT K1042ac is associated with IL-1ß expression and the prognosis of human gastric cancer. Our findings demonstrate a mechanism of IL-1ß-promoted tumor immune evasion, implicating the therapeutic potential of disrupting the link between IL-1ß and tumor cells by inhibiting NNT acetylation.


Asunto(s)
NADP Transhidrogenasas , Neoplasias , Humanos , NADP Transhidrogenasas/genética , NADP Transhidrogenasas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Acetilación , Procesamiento Proteico-Postraduccional , Inmunoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/genética
5.
Nature ; 626(7998): 411-418, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38297130

RESUMEN

Ferroptosis, a form of regulated cell death that is driven by iron-dependent phospholipid peroxidation, has been implicated in multiple diseases, including cancer1-3, degenerative disorders4 and organ ischaemia-reperfusion injury (IRI)5,6. Here, using genome-wide CRISPR-Cas9 screening, we identified that the enzymes involved in distal cholesterol biosynthesis have pivotal yet opposing roles in regulating ferroptosis through dictating the level of 7-dehydrocholesterol (7-DHC)-an intermediate metabolite of distal cholesterol biosynthesis that is synthesized by sterol C5-desaturase (SC5D) and metabolized by 7-DHC reductase (DHCR7) for cholesterol synthesis. We found that the pathway components, including MSMO1, CYP51A1, EBP and SC5D, function as potential suppressors of ferroptosis, whereas DHCR7 functions as a pro-ferroptotic gene. Mechanistically, 7-DHC dictates ferroptosis surveillance by using the conjugated diene to exert its anti-phospholipid autoxidation function and shields plasma and mitochondria membranes from phospholipid autoxidation. Importantly, blocking the biosynthesis of endogenous 7-DHC by pharmacological targeting of EBP induces ferroptosis and inhibits tumour growth, whereas increasing the 7-DHC level by inhibiting DHCR7 effectively promotes cancer metastasis and attenuates the progression of kidney IRI, supporting a critical function of this axis in vivo. In conclusion, our data reveal a role of 7-DHC as a natural anti-ferroptotic metabolite and suggest that pharmacological manipulation of 7-DHC levels is a promising therapeutic strategy for cancer and IRI.


Asunto(s)
Deshidrocolesteroles , Ferroptosis , Humanos , Membrana Celular/metabolismo , Colesterol/biosíntesis , Colesterol/metabolismo , Sistemas CRISPR-Cas/genética , Deshidrocolesteroles/metabolismo , Genoma Humano , Enfermedades Renales/metabolismo , Membranas Mitocondriales/metabolismo , Metástasis de la Neoplasia , Neoplasias/metabolismo , Neoplasias/patología , Fosfolípidos/metabolismo , Daño por Reperfusión/metabolismo
6.
Nature ; 610(7933): 656-660, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36289385

RESUMEN

Proposed mechanisms for the production of calcium in the first stars (population III stars)-primordial stars that formed out of the matter of the Big Bang-are at odds with observations1. Advanced nuclear burning and supernovae were thought to be the dominant source of the calcium production seen in all stars2. Here we suggest a qualitatively different path to calcium production through breakout from the 'warm' carbon-nitrogen-oxygen (CNO) cycle through a direct experimental measurement of the 19F(p, γ)20Ne breakout reaction down to a very low energy point of 186 kiloelectronvolts, reporting a key resonance at 225 kiloelectronvolts. In the domain of astrophysical interest2, at around 0.1 gigakelvin, this thermonuclear 19F(p, γ)20Ne rate is up to a factor of 7.4 larger than the previous recommended rate3. Our stellar models show a stronger breakout during stellar hydrogen burning than previously thought1,4,5, and may reveal the nature of calcium production in population III stars imprinted on the oldest known ultra-iron-poor star, SMSS0313-67086. Our experimental result was obtained in the China JinPing Underground Laboratory7, which offers an environment with an extremely low cosmic-ray-induced background8. Our rate showcases the effect that faint population III star supernovae can have on the nucleosynthesis observed in the oldest known stars and first galaxies, which are key mission targets of the James Webb Space Telescope9.

7.
PLoS Pathog ; 20(5): e1012266, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38787906

RESUMEN

Mycoplasmas are minimal but notorious bacteria that infect humans and animals. These genome-reduced organisms have evolved strategies to overcome host apoptotic defense and establish persistent infection. Here, using Mycoplasma bovis as a model, we demonstrate that mycoplasma glycine cleavage system (GCS) H protein (GcvH) targets the endoplasmic reticulum (ER) to hijack host apoptosis facilitating bacterial infection. Mechanically, GcvH interacts with the ER-resident kinase Brsk2 and stabilizes it by blocking its autophagic degradation. Brsk2 subsequently disturbs unfolded protein response (UPR) signaling, thereby inhibiting the key apoptotic molecule CHOP expression and ER-mediated intrinsic apoptotic pathway. CHOP mediates a cross-talk between ER- and mitochondria-mediated intrinsic apoptosis. The GcvH N-terminal amino acid 31-35 region is necessary for GcvH interaction with Brsk2, as well as for GcvH to exert anti-apoptotic and potentially pro-infective functions. Notably, targeting Brsk2 to dampen apoptosis may be a conserved strategy for GCS-containing mycoplasmas. Our study reveals a novel role for the conserved metabolic route protein GcvH in Mycoplasma species. It also sheds light on how genome-reduced bacteria exploit a limited number of genomic proteins to resist host cell apoptosis thereby facilitating pathogenesis.


Asunto(s)
Apoptosis , Proteínas Bacterianas , Retículo Endoplásmico , Humanos , Retículo Endoplásmico/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Animales , Infecciones por Mycoplasma/metabolismo , Infecciones por Mycoplasma/microbiología , Mycoplasma bovis/metabolismo , Glicina/metabolismo , Respuesta de Proteína Desplegada , Proteínas Serina-Treonina Quinasas/metabolismo
8.
J Immunol ; 212(8): 1334-1344, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38391367

RESUMEN

Various subspecies of the unicellular parasite Trypanosoma brucei cause sleeping sickness, a neglected tropical disease affecting millions of individuals and domestic animals. Immune evasion mechanisms play a pivotal role in parasite survival within the host and enable the parasite to establish a chronic infection. In particular, the rapid switching of variant surface glycoproteins covering a large proportion of the parasite's surface enables the parasite to avoid clearance by the adaptive immune system of the host. In this article, we present the crystal structure and discover an immune-evasive function of the extracellular region of the T. brucei invariant surface gp75 (ISG75). Structural analysis determined that the ISG75 ectodomain is organized as a globular head domain and a long slender coiled-coil domain. Subsequent ligand screening and binding analysis determined that the head domain of ISG75 confers interaction with the Fc region of all subclasses of human IgG. Importantly, the ISG75-IgG interaction strongly inhibits both activation of the classical complement pathway and Ab-dependent cellular phagocytosis by competing with C1q and host cell FcγR CD32. Our data reveal a novel immune evasion mechanism of T. brucei, with ISG75 able to inactivate the activities of Abs recognizing the parasite surface proteins.


Asunto(s)
Trypanosoma brucei brucei , Animales , Humanos , Receptores Fc/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Portadoras/metabolismo , Inmunoglobulina G/metabolismo , Fagocitosis , Activación de Complemento
9.
Proc Natl Acad Sci U S A ; 120(52): e2305684120, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38113258

RESUMEN

Metastasis is a major cause of cancer therapy failure and mortality. However, targeting metastatic seeding and colonization remains a significant challenge. In this study, we identified NSD2, a histone methyltransferase responsible for dimethylating histone 3 at lysine 36, as being overexpressed in metastatic tumors. Our findings suggest that NSD2 overexpression enhances tumor metastasis both in vitro and in vivo. Further analysis revealed that NSD2 promotes tumor metastasis by activating Rac1 signaling. Mechanistically, NSD2 combines with and activates Tiam1 (T lymphoma invasion and metastasis 1) and promotes Rac1 signaling by methylating Tiam1 at K724. In vivo and in vitro studies revealed that Tiam1 K724 methylation could be a predictive factor for cancer prognosis and a potential target for metastasis inhibition. Furthermore, we have developed inhibitory peptide which was proved to inhibit tumor metastasis through blocking the interaction between NSD2 and Tiam1. Our results demonstrate that NSD2-methylated Tiam1 promotes Rac1 signaling and cancer metastasis. These results provide insights into the inhibition of tumor metastasis.


Asunto(s)
Neoplasias del Colon , Factores de Intercambio de Guanina Nucleótido , Humanos , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Transducción de Señal/fisiología , Invasividad Neoplásica/patología , Metilación , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo
10.
Development ; 149(1)2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34931663

RESUMEN

Alveologenesis requires the coordinated modulation of the epithelial and mesenchymal compartments to generate mature alveolar saccules for efficient gas exchange. However, the molecular mechanisms underlying the epithelial-mesenchymal interaction during alveologenesis are poorly understood. Here, we report that Wnts produced by epithelial cells are crucial for neonatal alveologenesis. Deletion of the Wnt chaperone protein Wntless homolog (Wls) disrupts alveolar formation, resulting in enlarged saccules in Sftpc-Cre/Nkx2.1-Cre; Wlsloxp/loxp mutants. Although commitment of the alveolar epithelium is unaffected, α-SMA+ mesenchymal cells persist in the alveoli, accompanied by increased collagen deposition, and mutants exhibit exacerbated fibrosis following bleomycin challenge. Notably, α-SMA+ cells include a significant number of endothelial cells resembling endothelial to mesenchymal transition (EndMT), which is also present in Ager-CreER; Wlsloxp/loxp mutants following early postnatal Wls deletion. These findings provide initial evidence that epithelial-derived Wnts are crucial for the differentiation of the surrounding mesenchyme during early postnatal alveologenesis.


Asunto(s)
Células Epiteliales Alveolares/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Actinas/genética , Actinas/metabolismo , Células Epiteliales Alveolares/citología , Animales , Células Cultivadas , Transición Epitelial-Mesenquimal , Ratones , Ratones Endogámicos C57BL , Receptores Acoplados a Proteínas G/genética
11.
Nat Mater ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977883

RESUMEN

Despite the potential of oral immunotherapy against food allergy, adverse reactions and loss of desensitization hinder its clinical uptake. Dysbiosis of the gut microbiota is implicated in the increasing prevalence of food allergy, which will need to be regulated to enable for an effective oral immunotherapy against food allergy. Here we report an inulin gel formulated with an allergen that normalizes the dysregulated ileal microbiota and metabolites in allergic mice, establishes allergen-specific oral tolerance and achieves robust oral immunotherapy efficacy with sustained unresponsiveness in food allergy models. These positive outcomes are associated with enhanced allergen uptake by antigen-sampling dendritic cells in the small intestine, suppressed pathogenic type 2 immune responses, increased interferon-γ+ and interleukin-10+ regulatory T cell populations, and restored ileal abundances of Eggerthellaceae and Enterorhabdus in allergic mice. Overall, our findings underscore the therapeutic potential of the engineered allergen gel as a suitable microbiome-modulating platform for food allergy and other allergic diseases.

12.
Plant Physiol ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743701

RESUMEN

Maize (Zea mays L.) has very strong requirements for nitrogen. However, the molecular mechanisms underlying the regulations of nitrogen uptake and translocation in this species are not fully understood. Here, we report that an APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor ZmEREB97 functions as an important regulator in the N-signaling network in maize. Predominantly expressed and accumulated in main root and lateral root primordia, ZmEREB97 rapidly responded to nitrate treatment. By overlapping the analyses of differentially expressed genes and conducting a DAP-seq assay, we identified 1446 potential target genes of ZmEREB97. Among these, 764 genes were co-regulated in two lines of zmereb97 mutants. Loss of function of ZmEREB97 substantially weakened plant growth under both hydroponic and soil conditions. Physiological characterization of zmereb97 mutant plants demonstrated that reduced biomass and grain yield were both associated with reduced nitrate influx, decreased nitrate content and less N accumulation. We further demonstrated that ZmEREB97 directly targets and regulates the expression of six ZmNRT genes by binding to the GCC box-related sequences in gene promoters. Collectively, these data suggest that ZmEREB97 is a major positive regulator of the nitrate response and that it plays an important role in optimizing nitrate uptake, offering a target for improvement of nitrogen use efficiency in crops.

13.
Plant Physiol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833579

RESUMEN

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.

14.
Nature ; 567(7749): 525-529, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30814730

RESUMEN

T cells become dysfunctional when they encounter self antigens or are exposed to chronic infection or to the tumour microenvironment1. The function of T cells is tightly regulated by a combinational co-stimulatory signal, and dominance of negative co-stimulation results in T cell dysfunction2. However, the molecular mechanisms that underlie this dysfunction remain unclear. Here, using an in vitro T cell tolerance induction system in mice, we characterize genome-wide epigenetic and gene expression features in tolerant T cells, and show that they are distinct from effector and regulatory T cells. Notably, the transcription factor NR4A1 is stably expressed at high levels in tolerant T cells. Overexpression of NR4A1 inhibits effector T cell differentiation, whereas deletion of NR4A1 overcomes T cell tolerance and exaggerates effector function, as well as enhancing immunity against tumour and chronic virus. Mechanistically, NR4A1 is preferentially recruited to binding sites of the transcription factor AP-1, where it represses effector-gene expression by inhibiting AP-1 function. NR4A1 binding also promotes acetylation of histone 3 at lysine 27 (H3K27ac), leading to activation of tolerance-related genes. This study thus identifies NR4A1 as a key general regulator in the induction of T cell dysfunction, and a potential target for tumour immunotherapy.


Asunto(s)
Regulación de la Expresión Génica/genética , Genoma , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Linfocitos T/metabolismo , Linfocitos T/patología , Acetilación , Animales , Infecciones por Arenaviridae/inmunología , Infecciones por Arenaviridae/virología , Línea Celular Tumoral , Colitis/inmunología , Colitis/patología , Colitis/terapia , Epigénesis Genética , Femenino , Histonas/química , Histonas/metabolismo , Tolerancia Inmunológica/genética , Inmunoterapia , Virus de la Coriomeningitis Linfocítica/inmunología , Ratones , Ratones Endogámicos C57BL , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/terapia , Linfocitos T/inmunología , Factor de Transcripción AP-1/metabolismo , Transcripción Genética
15.
Cereb Cortex ; 34(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38615238

RESUMEN

Intolerance of uncertainty (IU) is associated with several anxiety disorders. In this study, we employed rewards and losses as unconditioned positive and negative stimuli, respectively, to explore the effects of an individual's IU level on positive and negative generalizations using magnetic resonance imaging technology. Following instrumental learning, 48 participants (24 high IU; 24 low IU) were invited to complete positive and negative generalization tasks; their behavioral responses and neural activities were recorded by functional magnetic resonance imaging. The behavior results demonstrated that participants with high IUs exhibited higher generalizations to both positive and negative cues as compared with participants having low IUs. Neuroimaging results demonstrated that they exhibited higher activation levels in the right anterior insula and the default mode network (i.e. precuneus and posterior cingulate gyrus), as well as related reward circuits (i.e. caudate and right putamen). Therefore, higher generalization scores and the related abnormal brain activation may be key markers of IU as a vulnerability factor for anxiety disorders.


Asunto(s)
Ansiedad , Encéfalo , Humanos , Incertidumbre , Encéfalo/diagnóstico por imagen , Condicionamiento Operante , Señales (Psicología)
16.
Proc Natl Acad Sci U S A ; 119(50): e2210338119, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36472959

RESUMEN

Salt stress impairs nutrient metabolism in plant cells, leading to growth and yield penalties. However, the mechanism by which plants alter their nutrient metabolism processes in response to salt stress remains elusive. In this study, we identified and characterized the rice (Oryza sativa) rice salt tolerant 1 (rst1) mutant, which displayed improved salt tolerance and grain yield. Map-based cloning revealed that the gene RST1 encoded an auxin response factor (OsARF18). Molecular analyses showed that RST1 directly repressed the expression of the gene encoding asparagine synthetase 1 (OsAS1). Loss of RST1 function increased the expression of OsAS1 and improved nitrogen (N) utilization by promoting asparagine production and avoiding excess ammonium (NH4+) accumulation. RST1 was undergoing directional selection during domestication. The superior haplotype RST1Hap III decreased its transcriptional repression activity and contributed to salt tolerance and grain weight. Together, our findings unravel a synergistic regulator of growth and salt tolerance associated with N metabolism and provide a new strategy for the development of tolerant cultivars.


Asunto(s)
Aspartatoamoníaco Ligasa , Oryza , Tolerancia a la Sal/genética , Oryza/genética , Aspartatoamoníaco Ligasa/genética , Expresión Génica
17.
J Cell Mol Med ; 28(1): e18037, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37974543

RESUMEN

The tumour microenvironment (TME) is crucial for tumour development and progression. Tumour-associated macrophages (TAMs) in the TME can promote tumour progression and metastasis by releasing cytokines, such as IL-6. Calycosin, a phytoestrogen that is one of the active compounds in Radix Astragali, has been shown to inhibit tumour growth and metastasis. However, the underlying mechanism by which calycosin inhibits tumour growth remains unclear. Thus, this study aimed to investigate the effect of calycosin on IL-6 production in peripheral blood mononuclear cell (PBMC)- and THP-1-derived macrophages and explore its potential mechanisms using co-immunoprecipitation, western blotting, immunofluorescence, chromatin immunoprecipitation and luciferase assays. We found that calycosin treatment substantially upregulated the expression of ER-α36, a variant of the ER, and reduced IL-6 production in macrophages. Mechanistically, ER-α36 physically interacted with NF-κBp65 and retained p65 in the cytoplasm to attenuate NF-κB function as an IL-6 transcriptional inducer. In conclusion, our result indicated that calycosin inhibited IL-6 production by enhancing ER-α36 expression and its interaction with p65, which attenuated NF-κB function as an IL-6 inducer. Therefore, calycosin can be developed as an effective agent for cancer therapy by targeting TAMs.


Asunto(s)
Receptor alfa de Estrógeno , Isoflavonas , FN-kappa B , Neoplasias , Humanos , FN-kappa B/metabolismo , Transducción de Señal , Interleucina-6/metabolismo , Leucocitos Mononucleares/metabolismo , Macrófagos/metabolismo , Neoplasias/metabolismo , Microambiente Tumoral
18.
Plant J ; 116(2): 467-477, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37422899

RESUMEN

The Casparian strip (CS) is a cell wall modification made of lignin that functions as an apoplastic barrier in the root endodermis to restrict nutrient and water transport between the soil and stele. CS formation is affected by nutritional conditions, and its physiological roles have been discussed. This study found that low K condition affects CS permeability, lignin deposition, and MYB36 mRNA accumulation. To understand the mechanism underlying these findings, we focused on nitric oxide (NO). NO is known to act as a signaling molecule and participates in cell wall synthesis, especially for lignin composition. However, the mechanism by which NO affects lignin deposition and corrects CS formation in the plant roots remains unclear. Through combining fluorescent observation with histological stains, we demonstrated that the root endodermal cell lignification response to low-potassium (K) conditions is mediated by NO through the MYB36-associated lignin-polymerizing pathway. Furthermore, we discovered the noteworthy ability of NO to maintain nutrient homeostasis for adaptation to low K conditions by affecting the correct apoplastic barrier formation of CS. Collectively, our results suggest that NO is required for the lignification and apoplastic barrier formation in the root endodermis during adaptation to low K conditions, which revealing the novel physiological roles of CS under low nutrient conditions and making a significant contribution to CS biology.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Óxido Nítrico/metabolismo , Lignina/metabolismo , Raíces de Plantas/metabolismo , Pared Celular/metabolismo , Diferenciación Celular
19.
Plant J ; 116(1): 201-216, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37381632

RESUMEN

High-affinity K+ transporters/K+ uptake permeases/K+ transporters (HAK/KUP/KT) are important pathways mediating K+ transport across cell membranes, which function in maintaining K+ homeostasis during plant growth and stress response. An increasing number of studies have shown that HAK/KUP/KT transporters play crucial roles in root K+ uptake and root-to-shoot translocation. However, whether HAK/KUP/KT transporters also function in phloem K+ translocation remain unclear. In this study, we revealed that a phloem-localized rice HAK/KUP/KT transporter, OsHAK18, mediated cell K+ uptake when expressed in yeast, Escherichia coli and Arabidopsis. It was localized at the plasma membrane. Disruption of OsHAK18 rendered rice seedlings insensitive to low-K+ (LK) stress. After LK stress, some WT leaves showed severe wilting and chlorosis, whereas the corresponding leaves of oshak18 mutant lines (a Tos17 insertion line and two CRISPR lines) remained green and unwilted. Compared with WT, the oshak18 mutants accumulated more K+ in shoots but less K+ in roots after LK stress, leading to a higher shoot/root ratio of K+ per plant. Disruption of OsHAK18 does not affect root K+ uptake and K+ level in xylem sap, but it significantly decreases phloem K+ concentration and inhibits root-to-shoot-to-root K+ (Rb+ ) translocation in split-root assay. These results reveal that OsHAK18 mediates phloem K+ loading and redistribution, whose disruption is in favor of shoot K+ retention under LK stress. Our findings expand the understanding of HAK/KUP/KT transporters' functions and provide a promising strategy for improving rice tolerance to K+ deficiency.


Asunto(s)
Arabidopsis , Oryza , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Potasio/metabolismo , Floema/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Saccharomyces cerevisiae/metabolismo , Raíces de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
20.
BMC Genomics ; 25(1): 117, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38279081

RESUMEN

BACKGROUND: In cellular activities, essential proteins play a vital role and are instrumental in comprehending fundamental biological necessities and identifying pathogenic genes. Current deep learning approaches for predicting essential proteins underutilize the potential of gene expression data and are inadequate for the exploration of dynamic networks with limited evaluation across diverse species. RESULTS: We introduce ECDEP, an essential protein identification model based on evolutionary community discovery. ECDEP integrates temporal gene expression data with a protein-protein interaction (PPI) network and employs the 3-Sigma rule to eliminate outliers at each time point, constructing a dynamic network. Next, we utilize edge birth and death information to establish an interaction streaming source to feed into the evolutionary community discovery algorithm and then identify overlapping communities during the evolution of the dynamic network. SVM recursive feature elimination (RFE) is applied to extract the most informative communities, which are combined with subcellular localization data for classification predictions. We assess the performance of ECDEP by comparing it against ten centrality methods, four shallow machine learning methods with RFE, and two deep learning methods that incorporate multiple biological data sources on Saccharomyces. Cerevisiae (S. cerevisiae), Homo sapiens (H. sapiens), Mus musculus, and Caenorhabditis elegans. ECDEP achieves an AP value of 0.86 on the H. sapiens dataset and the contribution ratio of community features in classification reaches 0.54 on the S. cerevisiae (Krogan) dataset. CONCLUSIONS: Our proposed method adeptly integrates network dynamics and yields outstanding results across various datasets. Furthermore, the incorporation of evolutionary community discovery algorithms amplifies the capacity of gene expression data in classification.


Asunto(s)
Mapas de Interacción de Proteínas , Saccharomyces cerevisiae , Animales , Ratones , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Algoritmos , Proteínas/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo
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