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1.
Nat Immunol ; 25(10): 1809-1819, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39261722

RESUMEN

Evolutionary pressures sculpt population genetics, whereas immune adaptation fortifies humans against life-threatening organisms. How the evolution of selective genetic variation in adaptive immune receptors orchestrates the adaptation of human populations to contextual perturbations remains elusive. Here, we show that the G396R coding variant within the human immunoglobulin G1 (IgG1) heavy chain presents a concentrated prevalence in Southeast Asian populations. We uncovered a 190-kb genomic linkage disequilibrium block peaked in close proximity to this variant, suggestive of potential Darwinian selection. This variant confers heightened immune resilience against various pathogens and viper toxins in mice. Mechanistic studies involving severe acute respiratory syndrome coronavirus 2 infection and vaccinated individuals reveal that this variant enhances pathogen-specific IgG1+ memory B cell activation and antibody production. This G396R variant may have arisen on a Neanderthal haplotype background. These findings underscore the importance of an IGHG1 variant in reinforcing IgG1 antibody responses against life-threatening organisms, unraveling the intricate interplay between human evolution and immune adaptation.


Asunto(s)
COVID-19 , Inmunoglobulina G , Cadenas Pesadas de Inmunoglobulina , SARS-CoV-2 , Humanos , Animales , Inmunoglobulina G/inmunología , COVID-19/inmunología , COVID-19/genética , SARS-CoV-2/inmunología , Ratones , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Desequilibrio de Ligamiento , Formación de Anticuerpos/genética , Formación de Anticuerpos/inmunología , Haplotipos , Células B de Memoria/inmunología , Femenino , Variación Genética , Masculino
2.
Nature ; 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39415002

RESUMEN

Human prenatal skin is populated by innate immune cells, including macrophages, but whether they act solely in immunity or have additional functions in morphogenesis is unclear. Here we assembled a comprehensive multi-omics reference atlas of prenatal human skin (7-17 post-conception weeks), combining single-cell and spatial transcriptomics data, to characterize the microanatomical tissue niches of the skin. This atlas revealed that crosstalk between non-immune and immune cells underpins the formation of hair follicles, is implicated in scarless wound healing and is crucial for skin angiogenesis. We systematically compared a hair-bearing skin organoid (SkO) model derived from human embryonic stem cells and induced pluripotent stem cells to prenatal and adult skin1. The SkO model closely recapitulated in vivo skin epidermal and dermal cell types during hair follicle development and expression of genes implicated in the pathogenesis of genetic hair and skin disorders. However, the SkO model lacked immune cells and had markedly reduced endothelial cell heterogeneity and quantity. Our in vivo prenatal skin cell atlas indicated that macrophages and macrophage-derived growth factors have a role in driving endothelial development. Indeed, vascular network remodelling was enhanced following transfer of autologous macrophages derived from induced pluripotent stem cells into SkO cultures. Innate immune cells are therefore key players in skin morphogenesis beyond their conventional role in immunity, a function they achieve through crosstalk with non-immune cells.

3.
Annu Rev Genet ; 55: 453-477, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34530641

RESUMEN

CRISPR-based genome editing holds promise for genome engineering and other applications in diverse organisms. Defining and improving the genome-wide and transcriptome-wide specificities of these editing tools are essential for realizing their full potential in basic research and biomedical therapeutics. This review provides an overview of CRISPR-based DNA- and RNA-editing technologies, methods to quantify their specificities, and key solutions to reduce off-target effects for research and improve therapeutic applications.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Sistemas CRISPR-Cas/genética , ADN/genética , Genoma/genética , Transcriptoma
4.
Nature ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057666

RESUMEN

Human limbs emerge during the fourth post-conception week as mesenchymal buds, which develop into fully formed limbs over the subsequent months1. This process is orchestrated by numerous temporally and spatially restricted gene expression programmes, making congenital alterations in phenotype common2. Decades of work with model organisms have defined the fundamental mechanisms underlying vertebrate limb development, but an in-depth characterization of this process in humans has yet to be performed. Here we detail human embryonic limb development across space and time using single-cell and spatial transcriptomics. We demonstrate extensive diversification of cells from a few multipotent progenitors to myriad differentiated cell states, including several novel cell populations. We uncover two waves of human muscle development, each characterized by different cell states regulated by separate gene expression programmes, and identify musculin (MSC) as a key transcriptional repressor maintaining muscle stem cell identity. Through assembly of multiple anatomically continuous spatial transcriptomic samples using VisiumStitcher, we map cells across a sagittal section of a whole fetal hindlimb. We reveal a clear anatomical segregation between genes linked to brachydactyly and polysyndactyly, and uncover transcriptionally and spatially distinct populations of the mesenchyme in the autopod. Finally, we perform single-cell RNA sequencing on mouse embryonic limbs to facilitate cross-species developmental comparison, finding substantial homology between the two species.

5.
Nature ; 607(7919): 540-547, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35794482

RESUMEN

Gonadal development is a complex process that involves sex determination followed by divergent maturation into either testes or ovaries1. Historically, limited tissue accessibility, a lack of reliable in vitro models and critical differences between humans and mice have hampered our knowledge of human gonadogenesis, despite its importance in gonadal conditions and infertility. Here, we generated a comprehensive map of first- and second-trimester human gonads using a combination of single-cell and spatial transcriptomics, chromatin accessibility assays and fluorescent microscopy. We extracted human-specific regulatory programmes that control the development of germline and somatic cell lineages by profiling equivalent developmental stages in mice. In both species, we define the somatic cell states present at the time of sex specification, including the bipotent early supporting population that, in males, upregulates the testis-determining factor SRY and sPAX8s, a gonadal lineage located at the gonadal-mesonephric interface. In females, we resolve the cellular and molecular events that give rise to the first and second waves of granulosa cells that compartmentalize the developing ovary to modulate germ cell differentiation. In males, we identify human SIGLEC15+ and TREM2+ fetal testicular macrophages, which signal to somatic cells outside and inside the developing testis cords, respectively. This study provides a comprehensive spatiotemporal map of human and mouse gonadal differentiation, which can guide in vitro gonadogenesis.


Asunto(s)
Linaje de la Célula , Células Germinativas , Ovario , Diferenciación Sexual , Análisis de la Célula Individual , Testículo , Animales , Cromatina/genética , Cromatina/metabolismo , Femenino , Células Germinativas/citología , Células Germinativas/metabolismo , Células de la Granulosa/citología , Células de la Granulosa/metabolismo , Humanos , Inmunoglobulinas , Macrófagos/metabolismo , Masculino , Glicoproteínas de Membrana , Proteínas de la Membrana , Ratones , Microscopía Fluorescente , Ovario/citología , Ovario/embriología , Factor de Transcripción PAX8 , Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Receptores Inmunológicos , Diferenciación Sexual/genética , Testículo/citología , Testículo/embriología , Transcriptoma
6.
Nature ; 611(7936): 594-602, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36352222

RESUMEN

Genome sequencing of cancers often reveals mosaics of different subclones present in the same tumour1-3. Although these are believed to arise according to the principles of somatic evolution, the exact spatial growth patterns and underlying mechanisms remain elusive4,5. Here, to address this need, we developed a workflow that generates detailed quantitative maps of genetic subclone composition across whole-tumour sections. These provide the basis for studying clonal growth patterns, and the histological characteristics, microanatomy and microenvironmental composition of each clone. The approach rests on whole-genome sequencing, followed by highly multiplexed base-specific in situ sequencing, single-cell resolved transcriptomics and dedicated algorithms to link these layers. Applying the base-specific in situ sequencing workflow to eight tissue sections from two multifocal primary breast cancers revealed intricate subclonal growth patterns that were validated by microdissection. In a case of ductal carcinoma in situ, polyclonal neoplastic expansions occurred at the macroscopic scale but segregated within microanatomical structures. Across the stages of ductal carcinoma in situ, invasive cancer and lymph node metastasis, subclone territories are shown to exhibit distinct transcriptional and histological features and cellular microenvironments. These results provide examples of the benefits afforded by spatial genomics for deciphering the mechanisms underlying cancer evolution and microenvironmental ecology.


Asunto(s)
Neoplasias de la Mama , Carcinoma Intraductal no Infiltrante , Evolución Clonal , Células Clonales , Genómica , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/genética , Carcinoma Intraductal no Infiltrante/patología , Evolución Clonal/genética , Células Clonales/metabolismo , Células Clonales/patología , Mutación , Microambiente Tumoral/genética , Secuenciación Completa del Genoma , Transcriptoma , Reproducibilidad de los Resultados , Microdisección , Algoritmos
7.
Immunity ; 48(4): 675-687.e7, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29653696

RESUMEN

Manganese (Mn) is essential for many physiological processes, but its functions in innate immunity remain undefined. Here, we found that Mn2+ was required for the host defense against DNA viruses by increasing the sensitivity of the DNA sensor cGAS and its downstream adaptor protein STING. Mn2+ was released from membrane-enclosed organelles upon viral infection and accumulated in the cytosol where it bound directly to cGAS. Mn2+ enhanced the sensitivity of cGAS to double-stranded DNA (dsDNA) and its enzymatic activity, enabling cGAS to produce secondary messenger cGAMP in the presence of low concentrations of dsDNA that would otherwise be non-stimulatory. Mn2+ also enhanced STING activity by augmenting cGAMP-STING binding affinity. Mn-deficient mice showed diminished cytokine production and were more vulnerable to DNA viruses, and Mn-deficient STING-deficient mice showed no increased susceptibility. These findings indicate that Mn is critically involved and required for the host defense against DNA viruses.


Asunto(s)
Infecciones por Virus ADN/inmunología , Virus ADN/inmunología , ADN Viral/inmunología , Manganeso/metabolismo , Proteínas de la Membrana/metabolismo , Nucleotidiltransferasas/metabolismo , Adulto , Animales , Línea Celular , Cricetinae , Activación Enzimática/inmunología , Femenino , Células HEK293 , Células HeLa , Interacciones Huésped-Patógeno , Humanos , Inmunidad Innata/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Adulto Joven
8.
PLoS Biol ; 22(7): e3002721, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39008524

RESUMEN

The abundance of distractors in the world poses a major challenge to our brain's limited processing capacity, but little is known about how selective attention modulates stimulus representations in the brain to reduce interference and support durable target memory. Here, we collected functional magnetic resonance imaging (fMRI) data in a selective attention task in which target and distractor pictures of different visual categories were simultaneously presented. Participants were asked to selectively process the target according to the effective cue, either before the encoding period (i.e., perceptual attention) or the maintenance period (i.e., reflective attention). On the next day, participants were asked to perform a memory recognition task in the scanner in which the targets, distractors, and novel items were presented in a pseudorandom order. Behavioral results showed that perceptual attention was better at enhancing target memory and reducing distractor memory than reflective attention, although the overall memory capacity (memory for both target and distractor) was comparable. Using multiple-voxel pattern analysis of the neural data, we found more robust target representation and weaker distractor representation in working memory for perceptual attention than for reflective attention. Interestingly, perceptual attention partially shifted the regions involved in maintaining the target representation from the visual cortex to the parietal cortex. Furthermore, the targets and distractors simultaneously presented in the perceptual attention condition showed reduced pattern similarity in the parietal cortex during retrieval compared to items not presented together. This neural pattern repulsion positively correlated with individuals' recognition of both targets and distractors. These results emphasize the critical role of selective attention in transforming memory representations to reduce interference and improve long-term memory performance.


Asunto(s)
Atención , Imagen por Resonancia Magnética , Memoria a Largo Plazo , Memoria a Corto Plazo , Lóbulo Parietal , Humanos , Atención/fisiología , Lóbulo Parietal/fisiología , Masculino , Memoria a Corto Plazo/fisiología , Femenino , Memoria a Largo Plazo/fisiología , Adulto , Adulto Joven , Objetivos , Mapeo Encefálico , Estimulación Luminosa/métodos , Percepción Visual/fisiología
9.
Mol Cell ; 75(1): 102-116.e9, 2019 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31128943

RESUMEN

Transcription regulation underlies stem cell function and development. Here, we elucidate an unexpected role of an essential ribogenesis factor, WDR43, as a chromatin-associated RNA-binding protein (RBP) and release factor in modulating the polymerase (Pol) II activity for pluripotency regulation. WDR43 binds prominently to promoter-associated noncoding/nascent RNAs, occupies thousands of gene promoters and enhancers, and interacts with the Pol II machinery in embryonic stem cells (ESCs). Nascent transcripts and transcription recruit WDR43 to active promoters, where WDR43 facilitates releases of the elongation factor P-TEFb and paused Pol II. Knockdown of WDR43 causes genome-wide defects in Pol II release and pluripotency-associated gene expression. Importantly, auxin-mediated rapid degradation of WDR43 drastically reduces Pol II activity, precluding indirect consequences. These results reveal an RNA-mediated recruitment and feedforward regulation on transcription and demonstrate an unforeseen role of an RBP in promoting Pol II elongation and coordinating high-level transcription and translation in ESC pluripotency.


Asunto(s)
Proteínas de Transporte de Catión/genética , Cromatina/química , Regulación del Desarrollo de la Expresión Génica , Células Madre Embrionarias de Ratones/metabolismo , ARN Polimerasa II/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Transcripción Genética , Proteínas de Pez Cebra/genética , Animales , Sitios de Unión , Proteínas de Transporte de Catión/metabolismo , Diferenciación Celular , Línea Celular , Cromatina/metabolismo , Embrión de Mamíferos , Elementos de Facilitación Genéticos , Eliminación de Gen , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Células Madre Embrionarias de Ratones/citología , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Factor B de Elongación Transcripcional Positiva/genética , Factor B de Elongación Transcripcional Positiva/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Biosíntesis de Proteínas , Proteolisis , ARN Polimerasa II/metabolismo , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Transducción de Señal , Proteínas de Pez Cebra/metabolismo
10.
Proc Natl Acad Sci U S A ; 121(38): e2411747121, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39254994

RESUMEN

Detection of cytosolic DNA by the cyclic GMP-AMP (cGAMP) synthase (cGAS)-stimulator of interferon genes (STING) pathway provides immune defense against pathogens and cancer but can also cause autoimmunity when overactivated. The exonuclease three prime repair exonuclease 1 (TREX1) degrades DNA in the cytosol and prevents cGAS activation by self-DNA. Loss-of-function mutations of the TREX1 gene are linked to autoimmune diseases such as Aicardi-Goutières syndrome, and mice deficient in TREX1 develop lethal inflammation in a cGAS-dependent manner. In order to determine the type of cells in which cGAS activation drives autoinflammation, we generated conditional cGAS knockout mice on the Trex1-/- background. Here, we show that genetic ablation of the cGAS gene in classical dendritic cells (cDCs), but not in macrophages, was sufficient to rescue Trex1-/- mice from all observed disease phenotypes including lethality, T cell activation, tissue inflammation, and production of antinuclear antibodies and interferon-stimulated genes. These results show that cGAS activation in cDC causes autoinflammation in response to self-DNA accumulated in the absence of TREX1.


Asunto(s)
Autoinmunidad , Células Dendríticas , Exodesoxirribonucleasas , Ratones Noqueados , Nucleotidiltransferasas , Fosfoproteínas , Animales , Exodesoxirribonucleasas/genética , Exodesoxirribonucleasas/deficiencia , Exodesoxirribonucleasas/metabolismo , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Nucleotidiltransferasas/deficiencia , Células Dendríticas/inmunología , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/inmunología , Ratones , Autoinmunidad/inmunología , Malformaciones del Sistema Nervioso/genética , Malformaciones del Sistema Nervioso/inmunología , Enfermedades Autoinmunes del Sistema Nervioso/inmunología , Enfermedades Autoinmunes del Sistema Nervioso/genética , Enfermedades Autoinmunes del Sistema Nervioso/patología , Inflamación/inmunología , Inflamación/genética , Macrófagos/inmunología , Macrófagos/metabolismo , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/genética
11.
Plant Cell ; 35(8): 2887-2909, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37132483

RESUMEN

The phytohormone ethylene plays an important role in promoting the softening of climacteric fruits, such as apples (Malus domestica); however, important aspects of the underlying regulatory mechanisms are not well understood. In this study, we identified apple MITOGEN-ACTIVATED PROTEIN KINASE 3 (MdMAPK3) as an important positive regulator of ethylene-induced apple fruit softening during storage. Specifically, we show that MdMAPK3 interacts with and phosphorylates the transcription factor NAM-ATAF1/2-CUC2 72 (MdNAC72), which functions as a transcriptional repressor of the cell wall degradation-related gene POLYGALACTURONASE1 (MdPG1). The increase in MdMAPK3 kinase activity was induced by ethylene, which promoted the phosphorylation of MdNAC72 by MdMAPK3. Additionally, MdPUB24 functions as an E3 ubiquitin ligase to ubiquitinate MdNAC72, resulting in its degradation via the 26S proteasome pathway, which was enhanced by ethylene-induced phosphorylation of MdNAC72 by MdMAPK3. The degradation of MdNAC72 increased the expression of MdPG1, which in turn promoted apple fruit softening. Notably, using variants of MdNAC72 that were mutated at specific phosphorylation sites, we observed that the phosphorylation state of MdNAC72 affected apple fruit softening during storage. This study thus reveals that the ethylene-MdMAPK3-MdNAC72-MdPUB24 module is involved in ethylene-induced apple fruit softening, providing insights into climacteric fruit softening.


Asunto(s)
Malus , Malus/genética , Malus/metabolismo , Frutas/metabolismo , Fosforilación , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Etilenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
12.
Nat Chem Biol ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147927

RESUMEN

As the evolutionary ancestor of Cas9 nuclease, IscB proteins serve as compact RNA-guided DNA endonucleases and nickases, making them strong candidates for base editing. Nevertheless, the narrow targeting scope limits the application of IscB systems; thus, it is necessary to find more IscBs that recognize different target-adjacent motifs (TAMs). Here, we identified 10 of 19 uncharacterized IscB proteins from uncultured microbes with activity in mammalian cells. Through protein and ωRNA engineering, we further enhanced the activity of IscB ortholog IscB.m16 and expanded its TAM scope from MRNRAA to NNNGNA, resulting in a variant named IscB.m16*. By fusing the deaminase domains with IscB.m16* nickase, we generated IscB.m16*-derived base editors that exhibited robust base-editing efficiency in mammalian cells and effectively restored Duchenne muscular dystrophy proteins in diseased mice through single adeno-associated virus delivery. Thus, this study establishes a set of compact base-editing tools for basic research and therapeutic applications.

13.
Nucleic Acids Res ; 52(5): 2212-2230, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38364871

RESUMEN

Nonreference sequences (NRSs) are DNA sequences present in global populations but absent in the current human reference genome. However, the extent and functional significance of NRSs in the human genomes and populations remains unclear. Here, we de novo assembled 539 genomes from five genetically divergent human populations using long-read sequencing technology, resulting in the identification of 5.1 million NRSs. These were merged into 45284 unique NRSs, with 29.7% being novel discoveries. Among these NRSs, 38.7% were common across the five populations, and 35.6% were population specific. The use of a graph-based pangenome approach allowed for the detection of 565 transcript expression quantitative trait loci on NRSs, with 426 of these being novel findings. Moreover, 26 NRS candidates displayed evidence of adaptive selection within human populations. Genes situated in close proximity to or intersecting with these candidates may be associated with metabolism and type 2 diabetes. Genome-wide association studies revealed 14 NRSs to be significantly associated with eight phenotypes. Additionally, 154 NRSs were found to be in strong linkage disequilibrium with 258 phenotype-associated SNPs in the GWAS catalogue. Our work expands the understanding of human NRSs and provides novel insights into their functions, facilitating evolutionary and biomedical researches.


Asunto(s)
Genoma Humano , Estudio de Asociación del Genoma Completo , Grupos de Población , Humanos , Diabetes Mellitus Tipo 2/genética , Desequilibrio de Ligamiento , Fenotipo , Polimorfismo de Nucleótido Simple , Genética de Población , Grupos de Población/genética
14.
Proc Natl Acad Sci U S A ; 120(44): e2308984120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37874858

RESUMEN

Leymus chinensis, a dominant perennial grass in the Eurasian Steppe, is well known for its remarkable adaptability and forage quality. Hardly any breeding has been done on the grass, limiting its potential in ecological restoration and forage productivity. To enable genetic improvement of the untapped, important species, we obtained a 7.85-Gb high-quality genome of L. chinensis with a particularly long contig N50 (318.49 Mb). Its allotetraploid genome is estimated to originate 5.29 million years ago (MYA) from a cross between the Ns-subgenome relating to Psathyrostachys and the unknown Xm-subgenome. Multiple bursts of transposons during 0.433-1.842 MYA after genome allopolyploidization, which involved predominantly the Tekay and Angela of LTR retrotransposons, contributed to its genome expansion and complexity. With the genome resource available, we successfully developed a genetic transformation system as well as the gene-editing pipeline in L. chinensis. We knocked out the monocot-specific miR528 using CRISPR/Cas9, resulting in the improvement of yield-related traits with increases in the tiller number and growth rate. Our research provides valuable genomic resources for Triticeae evolutionary studies and presents a conceptual framework illustrating the utilization of genomic information and genome editing to accelerate the improvement of wild L. chinensis with features such as polyploidization and self-incompatibility.


Asunto(s)
Fitomejoramiento , Poaceae , Poaceae/genética , Genoma , Evolución Molecular
15.
Plant J ; 118(5): 1358-1371, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38341799

RESUMEN

Watercore is a common physiological disease of Rosaceae plants, such as apples (Malus domestica), usually occurring during fruit ripening. Apple fruit with watercore symptoms is prone to browning and rotting, thus losing commercial viability. Sorbitol and calcium ions are considered key factors affecting watercore occurrence in apples. However, the mechanism by which they affect the occurrence of watercore remains unclear. Here, we identified that the transcription factor MdWRKY9 directly binds to the promoter of MdSOT2, positively regulates the transcription of MdSOT2, increases sorbitol content in fruit, and promotes watercore occurrence. Additionally, MdCRF4 can directly bind to MdWRKY9 and MdSOT2 promoters, positively regulating their expression. Since calcium ions can induce the ubiquitination and degradation of the transcription factor MdCRF4, they can inhibit the transcription of MdWRKY9 and MdSOT2 by degrading MdCRF4, thereby reducing the sorbitol content in fruit and inhibiting the occurrence of fruit watercore disease. Our data sheds light on how calcium ions mitigate watercore in fruit, providing molecular-level insights to enhance fruit quality artificially.


Asunto(s)
Calcio , Frutas , Regulación de la Expresión Génica de las Plantas , Malus , Proteínas de Plantas , Sorbitol , Factores de Transcripción , Malus/genética , Malus/metabolismo , Frutas/genética , Frutas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Calcio/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Sorbitol/metabolismo , Regiones Promotoras Genéticas/genética
16.
Plant J ; 118(5): 1312-1326, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38319894

RESUMEN

Lignin is an important component of plant cell walls and plays crucial roles in the essential agronomic traits of tea quality and tenderness. However, the molecular mechanisms underlying the regulation of lignin biosynthesis in tea plants remain unclear. CsWRKY13 acts as a negative regulator of lignin biosynthesis in tea plants. In this study, we identified a GRAS transcription factor, phytochrome A signal transduction 1 (CsPAT1), that interacts with CsWRKY13. Silencing CsPAT1 expression in tea plants and heterologous overexpression in Arabidopsis demonstrated that CsPAT1 positively regulates lignin accumulation. Further investigation revealed that CsWRKY13 directly binds to the promoters of CsPAL and CsC4H and suppresses transcription of CsPAL and CsC4H. CsPAT1 indirectly affects the promoter activities of CsPAL and CsC4H by interacting with CsWRKY13, thereby facilitating lignin biosynthesis in tea plants. Compared with the expression of CsWRKY13 alone, the co-expression of CsPAT1 and CsWRKY13 in Oryza sativa significantly increased lignin biosynthesis. Conversely, compared with the expression of CsPAT1 alone, the co-expression of CsPAT1 and CsWRKY13 in O. sativa significantly reduced lignin accumulation. These results demonstrated the antagonistic regulation of the lignin biosynthesis pathway by CsPAT1 and CsWRKY13. These findings improve our understanding of lignin biosynthesis mechanisms in tea plants and provide insights into the role of the GRAS transcription factor family in lignin accumulation.


Asunto(s)
Camellia sinensis , Regulación de la Expresión Génica de las Plantas , Lignina , Proteínas de Plantas , Factores de Transcripción , Lignina/metabolismo , Lignina/biosíntesis , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Camellia sinensis/genética , Camellia sinensis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética
17.
N Engl J Med ; 387(15): 1373-1384, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36239645

RESUMEN

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).


Asunto(s)
Arteriopatías Oclusivas , Arteria Basilar , Procedimientos Endovasculares , Accidente Cerebrovascular , Trombectomía , Humanos , Arteriopatías Oclusivas/complicaciones , Arteriopatías Oclusivas/tratamiento farmacológico , Arteriopatías Oclusivas/mortalidad , Arteriopatías Oclusivas/cirugía , Arteria Basilar/efectos de los fármacos , Arteria Basilar/cirugía , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/etiología , Isquemia Encefálica/mortalidad , Isquemia Encefálica/cirugía , Evaluación de la Discapacidad , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Fibrinolíticos/efectos adversos , Fibrinolíticos/uso terapéutico , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/etiología , Recuperación de la Función , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Accidente Cerebrovascular/cirugía , Trombectomía/efectos adversos , Trombectomía/métodos , Factores de Tiempo , Resultado del Tratamiento
18.
Eur J Immunol ; : e2350655, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973083

RESUMEN

Sepsis arises from an uncontrolled inflammatory response triggered by infection or stress, accompanied by alteration in cellular energy metabolism, and a strong correlation exists between these factors. Alpha-ketoglutarate (α-KG), an intermediate product of the TCA cycle, has the potential to modulate the inflammatory response and is considered a crucial link between energy metabolism and inflammation. The scavenger receptor (SR-A5), a significant pattern recognition receptor, assumes a vital function in anti-inflammatory reactions. In the current investigation, we have successfully illustrated the ability of α-KG to mitigate inflammatory factors in the serum of septic mice and ameliorate tissue damage. Additionally, α-KG has been shown to modulate metabolic reprogramming and macrophage polarization. Moreover, our findings indicate that the regulatory influence of α-KG on sepsis is mediated through SR-A5. We also elucidated the mechanism by which α-KG regulates SR-A5 expression and found that α-KG reduced the N6-methyladenosine level of macrophages by up-regulating the m6A demethylase ALKBH5. α-KG plays a crucial role in inhibiting inflammation by regulating SR-A5 expression through m6A demethylation during sepsis. The outcomes of this research provide valuable insights into the relationship between energy metabolism and inflammation regulation, as well as the underlying molecular regulatory mechanism.

19.
Hepatology ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779918

RESUMEN

BACKGROUND AND AIMS: Circulating tumor cells (CTCs) are precursors of cancer metastasis. However, how CTCs evade immunosurveillance during hematogenous dissemination remains unclear. APPROACH AND RESULTS: We identified CTC-platelet adhesions by single-cell RNA sequencing and multiplex immunofluorescence of blood samples from multiple cancer types. Clinically, CTC-platelet aggregates were associated with significantly shorter progression-free survival and overall survival in patients with HCC. In vitro, ex vivo, and in vivo assays demonstrated direct platelet adhesions gifted cancer cells with an evasive ability from NK cell killing by upregulating inhibitory checkpoint CD155 (PVR cell adhesion molecule), therefore facilitating distant metastasis. Mechanistically, CD155 was transcriptionally regulated by the FAK/JNK/c-Jun cascade in a platelet contact-dependent manner. Further competition assays and cytotoxicity experiments revealed that CD155 on CTCs inhibited NK-cell cytotoxicity only by engaging with immune receptor TIGIT, but not CD96 and DNAM1, another 2 receptors for CD155. Interrupting the CD155-TIGIT interactions with a TIGIT antibody restored NK-cell immunosurveillance on CTCs and markedly attenuated tumor metastasis. CONCLUSIONS: Our results demonstrated CTC evasion from NK-cell-mediated innate immunosurveillance mainly through immune checkpoint CD155-TIGIT, potentially offering an immunotherapeutic strategy for eradicating CTCs.

20.
Plant Physiol ; 195(3): 1906-1924, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38497551

RESUMEN

Root hairs (RHs), extensive structures of root epidermal cells, are important for plant nutrient acquisition, soil anchorage, and environmental interactions. Excessive production of the phytohormone ethylene (ET) leads to substantial root hair growth, manifested as tolerance to plant nutrient deficiencies. However, the molecular basis of ET production during root hair growth in response to nutrient starvation remains unknown. Herein, we found that a critical transcription factor, GLABRA 2 (GL2), inhibits ET production during root hair growth in Arabidopsis (Arabidopsis thaliana). GL2 directly binds to the promoter of the gene encoding ET OVERPRODUCER 1 (ETO1), one of the most important ET-production-regulation factors, in vitro and in vivo, and then regulates the accumulation and function of ETO1 in root hair growth. The GL2-regulated-ETO1 module is required for promoting root hair growth under nitrogen, phosphorus, or potassium deficiency. Genome-wide analysis revealed numerous genes, such as ROOT HAIR DEFECTIVE 6-LIKE 4, ETHYLENE-INSENSITIVE 3-LIKE 2, ROOT HAIR SPECIFIC 13, are involved in the GL2-regulated-ETO1 module. Our work reveals a key transcription mechanism in the control of ET production during root hair growth under three major nutrient deficiencies.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Etilenos , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas , Factores de Transcripción , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Arabidopsis/metabolismo , Etilenos/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Regiones Promotoras Genéticas/genética , Nitrógeno/metabolismo , Nitrógeno/deficiencia , Nutrientes/metabolismo , Fósforo/deficiencia , Fósforo/metabolismo , Proteínas de Homeodominio
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