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1.
Trends Genet ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38902139

RESUMEN

An i-motif (iM) is a four-stranded (quadruplex) DNA structure that folds from cytosine (C)-rich sequences. iMs can fold under many different conditions in vitro, which paves the way for their formation in living cells. iMs are thought to play key roles in various DNA transactions, notably in the regulation of genome stability, gene transcription, mRNA translation, DNA replication, telomere and centromere functions, and human diseases. We summarize the different techniques used to assess the folding of iMs in vitro and provide an overview of the internal and external factors that affect their formation and stability in vivo. We describe the possible biological relevance of iMs and propose directions towards their use as target in biology.

2.
Am J Hum Genet ; 110(7): 1162-1176, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37352861

RESUMEN

Large-scale genetic association studies have identified multiple susceptibility loci for nasopharyngeal carcinoma (NPC), but the underlying biological mechanisms remain to be explored. To gain insights into the genetic etiology of NPC, we conducted a follow-up study encompassing 6,907 cases and 10,472 controls and identified two additional NPC susceptibility loci, 9q22.33 (rs1867277; OR = 0.74, 95% CI = 0.68-0.81, p = 3.08 × 10-11) and 17q12 (rs226241; OR = 1.42, 95% CI = 1.26-1.60, p = 1.62 × 10-8). The two additional loci, together with two previously reported genome-wide significant loci, 5p15.33 and 9p21.3, were investigated by high-throughput sequencing for chromatin accessibility, histone modification, and promoter capture Hi-C (PCHi-C) profiling. Using luciferase reporter assays and CRISPR interference (CRISPRi) to validate the functional profiling, we identified PHF2 at locus 9q22.33 as a susceptibility gene. PHF2 encodes a histone demethylase and acts as a tumor suppressor. The risk alleles of the functional SNPs reduced the expression of the target gene PHF2 by inhibiting the enhancer activity of its long-range (4.3 Mb) cis-regulatory element, which promoted proliferation of NPC cells. In addition, we identified CDKN2B-AS1 as a susceptibility gene at locus 9p21.3, and the NPC risk allele of the functional SNP rs2069418 promoted the expression of CDKN2B-AS1 by increasing its enhancer activity. The overexpression of CDKN2B-AS1 facilitated proliferation of NPC cells. In summary, we identified functional SNPs and NPC susceptibility genes, which provides additional explanations for the genetic association signals and helps to uncover the underlying genetic etiology of NPC development.


Asunto(s)
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patología , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Estudios de Asociación Genética , Polimorfismo de Nucleótido Simple/genética , Proteínas de Homeodominio/genética
3.
Mol Cell ; 70(5): 894-905.e5, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29883608

RESUMEN

Despite considerable efforts, no physical mechanism has been shown to explain N-terminal codon bias in prokaryotic genomes. Using a systematic study of synonymous substitutions in two endogenous E. coli genes, we show that interactions between the coding region and the upstream Shine-Dalgarno (SD) sequence modulate the efficiency of translation initiation, affecting both intracellular mRNA and protein levels due to the inherent coupling of transcription and translation in E. coli. We further demonstrate that far-downstream mutations can also modulate mRNA levels by occluding the SD sequence through the formation of non-equilibrium secondary structures. By contrast, a non-endogenous RNA polymerase that decouples transcription and translation largely alleviates the effects of synonymous substitutions on mRNA levels. Finally, a complementary statistical analysis of the E. coli genome specifically implicates avoidance of intra-molecular base pairing with the SD sequence. Our results provide general physical insights into the coding-level features that optimize protein expression in prokaryotes.


Asunto(s)
Codón Iniciador , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Motivos de Nucleótidos , ARN Bacteriano/genética , ARN Mensajero/genética , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/biosíntesis , Regulación Bacteriana de la Expresión Génica , Genoma Bacteriano , Conformación de Ácido Nucleico , Biosíntesis de Proteínas , Estabilidad del ARN , ARN Bacteriano/biosíntesis , ARN Mensajero/biosíntesis , Relación Estructura-Actividad , Transcripción Genética
4.
Nucleic Acids Res ; 52(3): 1243-1257, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38180820

RESUMEN

I-motifs (iMs) are four-stranded non-B DNA structures containing C-rich DNA sequences. The formation of iMs is sensitive to pH conditions and DNA methylation, although the extent of which is still unknown in both humans and plants. To investigate this, we here conducted iMab antibody-based immunoprecipitation and sequencing (iM-IP-seq) along with bisulfite sequencing using CK (original genomic DNA without methylation-related treatments) and hypermethylated or demethylated DNA at both pH 5.5 and 7.0 in rice, establishing a link between pH, DNA methylation and iM formation on a genome-wide scale. We found that iMs folded at pH 7.0 displayed higher methylation levels than those formed at pH 5.5. DNA demethylation and hypermethylation differently influenced iM formation at pH 7.0 and 5.5. Importantly, CG hypo-DMRs (differentially methylated regions) and CHH (H = A, C and T) hyper-DMRs alone or coordinated with CG/CHG hyper-DMRs may play determinant roles in the regulation of pH dependent iM formation. Thus, our study shows that the nature of DNA sequences alone or combined with their methylation status plays critical roles in determining pH-dependent formation of iMs. It therefore deepens the understanding of the pH and methylation dependent modulation of iM formation, which has important biological implications and practical applications.


Asunto(s)
Metilación de ADN , Oryza , Humanos , ADN/genética , Genoma , Concentración de Iones de Hidrógeno , Oryza/genética
5.
Proc Natl Acad Sci U S A ; 120(10): e2216062120, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36857348

RESUMEN

SERRATE (SE) is a core protein for microRNA (miRNA) biogenesis as well as for mRNA alternative splicing. Investigating the regulatory mechanism of SE expression is hence critical to understanding its detailed function in diverse biological processes. However, little about the control of SE expression has been clarified, especially through long noncoding RNA (lncRNA). Here, we identified an antisense intragenic lncRNA transcribed from the 3' end of SE, named SEAIRa. SEAIRa repressed SE expression, which in turn led to serrated leaves. SEAIRa recruited plant U-box proteins PUB25/26 with unreported RNA binding ability and a ubiquitin-like protein related to ubiquitin 1 (RUB1) for H2A monoubiquitination (H2Aub) at exon 11 of SE. In addition, PUB25/26 helped cleave SEAIRa and release the 5' domain fragment, which recruited the PRC2 complex for H3 lysine 27 trimethylation (H3K27me3) deposition at the first exon of SE. The distinct modifications of H2Aub and H3K27me3 at different sites of the SE locus cooperatively suppressed SE expression. Collectively, our results uncover an epigenetic mechanism mediated by the lncRNA SEAIRa that modulates SE expression, which is indispensable for plant growth and development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Represión Epigenética , ARN Largo no Codificante , Proteínas de Unión al ARN , Epigénesis Genética , Histonas , ARN Largo no Codificante/genética , Proteínas de Arabidopsis/genética , Proteínas de Unión al ARN/genética
6.
Plant J ; 119(1): 137-152, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38569053

RESUMEN

Alternative splicing (AS) of pre-mRNAs increases the diversity of transcriptome and proteome and plays fundamental roles in plant development and stress responses. However, the prevalent changes in AS events and the regulating mechanisms of plants in response to pathogens remain largely unknown. Here, we show that AS changes are an important mechanism conferring cotton immunity to Verticillium dahliae (Vd). GauSR45a, encoding a serine/arginine-rich RNA binding protein, was upregulated expression and underwent AS in response to Vd infection in Gossypium australe, a wild diploid cotton species highly resistant to Vd. Silencing GauSR45a substantially reduced the splicing ratio of Vd-induced immune-associated genes, including GauBAK1 (BRI1-associated kinase 1) and GauCERK1 (chitin elicitor receptor kinase 1). GauSR45a binds to the GAAGA motif that is commonly found in the pre-mRNA of genes essential for PTI, ETI, and defense. The binding between GauSR45a and the GAAGA motif in the pre-mRNA of BAK1 was enhanced by two splicing factors of GauU2AF35B and GauU1-70 K, thereby facilitating exon splicing; silencing either AtU2AF35B or AtU1-70 K decreased the resistance to Vd in transgenic GauSR45a Arabidopsis. Overexpressing the short splicing variant of BAK1GauBAK1.1 resulted in enhanced Verticillium wilt resistance rather than the long one GauBAK1.2. Vd-induced far more AS events were in G. barbadense (resistant tetraploid cotton) than those in G. hirsutum (susceptible tetraploid cotton) during Vd infection, indicating resistance divergence in immune responses at a genome-wide scale. We provided evidence showing a fundamental mechanism by which GauSR45a enhances cotton resistance to Vd through global regulation of AS of immunity genes.


Asunto(s)
Empalme Alternativo , Ascomicetos , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Gossypium , Enfermedades de las Plantas , Proteínas de Plantas , Gossypium/genética , Gossypium/microbiología , Gossypium/inmunología , Empalme Alternativo/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiología , Inmunidad de la Planta/genética , Verticillium
7.
Trends Genet ; 38(10): 999-1002, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35853768

RESUMEN

Genome-wide studies of DNA G- and C-quadruplexes (G4s and i-motifs, respectively) can boost the pace of progress towards a comprehensive understanding of their biological implications and practical applications in plants. We summarize the current state of knowledge about omics studies in order to highlight the current challenges and propose future directions to take studies of plant quadruplexes to the next step.


Asunto(s)
G-Cuádruplex , ADN/genética , Plantas/genética
8.
Plant Physiol ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917225

RESUMEN

Single-stranded DNA (ssDNA) is essential for various DNA-templated processes in both eukaryotes and prokaryotes. However, comprehensive characterizations of ssDNA still lag in plants compared to non-plant systems. Here, we conducted in situ S1-seq (ISS1-seq), with starting gDNA ranging from 5 µg to 250 ng, followed by comprehensive characterizations of ssDNA in rice (Oryza sativa L.). We found that ssDNA loci were substantially associated with a subset of non-B DNA structures and functional genomic loci. Subtypes of ssDNA loci had distinct epigenetic features. Importantly, ssDNA may act alone or partly coordinate with non-B DNA structures, functional genomic loci, or epigenetic marks to actively or repressively modulate gene transcription, which is genomic-region-dependent and associated with the distinct accumulation of RNA Pol II. Moreover, distinct types of ssDNA had differential impacts on the activities and evolution of TEs (especially common or conserved TEs) in the rice genome. Our study showcases an antibody-independent technique for characterizing non-B DNA structures or functional genomic loci in plants. It lays the groundwork and fills a crucial gap for further exploration of ssDNA, non-B DNA structures, or functional genomic loci, thereby advancing our understanding of their biology in plants.

9.
Plant Physiol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38652695

RESUMEN

Centromeres in most multicellular eukaryotes are composed of long arrays of repetitive DNA sequences. Interestingly, several transposable elements, including the well-known long terminal repeat (LTR) retrotransposon CRM (centromeric retrotransposon of maize), were found to be enriched in functional centromeres marked by the centromeric histone H3 (CENH3). Here we report a centromeric long interspersed nuclear element (LINE), Celine, in Populus species. Celine has colonized preferentially in the CENH3-associated chromatin of every poplar chromosome, with 84% of the Celine elements localized in the CENH3-binding domains. By contrast, only 51% of the CRM elements were bound to CENH3 domains in Populus trichocarpa. These results suggest different centromere targeting mechanisms employed by Celine and CRM elements. Nevertheless, the high target specificity seems to be detrimental to further amplification of the Celine elements, leading to a shorter life span and patchy distribution among plant species compared to the CRM elements. Using a phylogenetically guided approach we were able to identify Celine-like LINE elements in tea plant (Camellia sinensis) and green ash tree (Fraxinus pennsylvanica). The centromeric localization of these Celine-like LINEs was confirmed in both species. We demonstrate that the centromere targeting property of Celine-like LINEs is of primitive origin and has been conserved among distantly related plant species.

10.
Blood ; 141(12): 1474-1488, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36574342

RESUMEN

Disorders of the ubiquitin-proteasome system (UPS) are known to influence the incidence and mortality of various diseases. It remains largely unknown whether and how the UPS affects the onset and progression of acute graft-verus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study demonstrated that the deubiquitinase OTUD1 is an essential regulator of aGVHD. Activation of CD4+ T cells after allo-HSCT, elevated the protein levels of OTUD1, which in turn interacted with the Notch2-ICD (NICD) to cleave the ubiquitin of NICD at the K1770 site, thereby inducing NICD protein accumulations in T cells. OTUD1-driven NICD signaling promoted the differentiation and functions of Th1 and Th17 cells and amplified the cascade of aGVHD. Moreover, by screening a FDA-approved drugs library the study identified dapagliflozin as an inhibitor targeting the OTUD1/NICD axis. Dapagliflozin administration significantly prolonged the survival of aGVHD mice. This study characterized a previously unknown role of OTUD1 in T cell-mediated allogeneic responses and provided a promising therapeutic strategy to target OTUD1 for the alleviation of aGVHD.


Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Animales , Ratones , Enfermedad Aguda , Linfocitos T CD4-Positivos/metabolismo , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ubiquitinas
11.
Plant Cell ; 34(9): 3425-3442, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-35642941

RESUMEN

Plants manage the high cost of immunity activation by suppressing the expression of defense genes during normal growth and rapidly switching them on upon pathogen invasion. TGAs are key transcription factors controlling the expression of defense genes. However, how TGAs function, especially in monocot plants like rice with continuously high levels of endogenous salicylic acid (SA) remains elusive. In this study, we characterized the role of OsTGA5 as a negative regulator of rice resistance against blast fungus by transcriptionally repressing the expression of various defense-related genes. Moreover, OsTGA5 repressed PTI responses and the accumulation of endogenous SA. Importantly, we showed that the nucleus-localized casein kinase II (CK2) complex interacts with and phosphorylates OsTGA5 on Ser-32, which reduces the affinity of OsTGA5 for the JIOsPR10 promoter, thereby alleviating the repression of JIOsPR10 transcription and increasing rice resistance. Furthermore, the in vivo phosphorylation of OsTGA5 Ser-32 was enhanced by blast fungus infection. The CK2 α subunit, depending on its kinase activity, positively regulated rice defense against blast fungus. Taken together, our results provide a mechanism for the role of OsTGA5 in negatively regulating the transcription of defense-related genes in rice and the repressive switch imposed by nuclear CK2-mediated phosphorylation during blast fungus invasion.


Asunto(s)
Magnaporthe , Oryza , Quinasa de la Caseína II , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Fosforilación , Enfermedades de las Plantas , Proteínas de Plantas , Ácido Salicílico , Transcripción Genética
12.
J Cell Mol Med ; 28(1): e18006, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850543

RESUMEN

Hepatoblastoma, the most frequently diagnosed primary paediatric liver tumour, bears the lowest somatic mutation burden among paediatric neoplasms. Therefore, it is essential to identify pathogenic germline genetic variants, especially those in oncogenic genes, for this disease. The tRNA methyltransferase 6 noncatalytic subunit (TRMT6) forms a tRNA methyltransferase complex with TRMT61A to catalyse adenosine methylation at position N1 of RNAs. TRMT6 has displayed tumour-promoting functions in several cancer types. However, the contribution of its genetic variants to hepatoblastoma remains unclear. In this study, we investigated the association between four TRMT6 polymorphisms (rs236170 A > G, rs451571 T > C, rs236188 G > A and rs236110 C > A) and the risk of hepatoblastoma in a cohort of 313 cases and 1446 healthy controls. Germline DNA was subjected to polymorphism genotyping via the TaqMan qPCR method. Odds ratio (OR) and 95% confidence interval (CI) were used to determine hepatoblastoma susceptibility variants. The rs236170 A > G, rs236188 G > A and rs236110 C > A polymorphisms were significantly associated with hepatoblastoma risk. Combination analysis of the four polymorphisms revealed that children bearing 1-4 risk genotypes were at significantly enhanced hepatoblastoma risk compared to those without risk genotype (adjusted OR = 1.52, 95% CI = 1.19-1.95, p = 0.0008). We also conducted stratification analyses by age, sex and clinical stage. Ultimately, we found that the rs236110 C > A was significantly associated with the downregulation of MCM8, a neighbouring gene of TRMT6. In conclusion, we identified three susceptibility loci in the TRMT6 gene for hepatoblastoma. Our findings warrant further validation by extensive case-control studies across different ethnicities.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Niño , Humanos , Hepatoblastoma/genética , Estudios de Casos y Controles , Neoplasias Hepáticas/genética , Polimorfismo Genético , ARNt Metiltransferasas/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple
13.
J Biol Chem ; 299(7): 104911, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37311534

RESUMEN

Reversible lysine-63 (K63) polyubiquitination regulates proinflammatory signaling in vascular smooth muscle cells (SMCs) and plays an integral role in atherosclerosis. Ubiquitin-specific peptidase 20 (USP20) reduces NFκB activation triggered by proinflammatory stimuli, and USP20 activity attenuates atherosclerosis in mice. The association of USP20 with its substrates triggers deubiquitinase activity; this association is regulated by phosphorylation of USP20 on Ser334 (mouse) or Ser333 (human). USP20 Ser333 phosphorylation was greater in SMCs of atherosclerotic segments of human arteries as compared with nonatherosclerotic segments. To determine whether USP20 Ser334 phosphorylation regulates proinflammatory signaling, we created USP20-S334A mice using CRISPR/Cas9-mediated gene editing. USP20-S334A mice developed ∼50% less neointimal hyperplasia than congenic WT mice after carotid endothelial denudation. WT carotid SMCs showed substantial phosphorylation of USP20 Ser334, and WT carotids demonstrated greater NFκB activation, VCAM-1 expression, and SMC proliferation than USP20-S334A carotids. Concordantly, USP20-S334A primary SMCs in vitro proliferated and migrated less than WT SMCs in response to IL-1ß. An active site ubiquitin probe bound to USP20-S334A and USP20-WT equivalently, but USP20-S334A associated more avidly with TRAF6 than USP20-WT. IL-1ß induced less K63-linked polyubiquitination of TRAF6 and less downstream NFκB activity in USP20-S334A than in WT SMCs. Using in vitro phosphorylation with purified IRAK1 and siRNA-mediated gene silencing of IRAK1 in SMCs, we identified IRAK1 as a novel kinase for IL-1ß-induced USP20 Ser334 phosphorylation. Our findings reveal novel mechanisms regulating IL-1ß-induced proinflammatory signaling: by phosphorylating USP20 Ser334, IRAK1 diminishes the association of USP20 with TRAF6 and thus augments NFκB activation, SMC inflammation, and neointimal hyperplasia.


Asunto(s)
Aterosclerosis , Inflamación , Quinasas Asociadas a Receptores de Interleucina-1 , Interleucina-1beta , Músculo Liso Vascular , Miocitos del Músculo Liso , Fosfoserina , Ubiquitina Tiolesterasa , Animales , Humanos , Ratones , Aterosclerosis/metabolismo , Aterosclerosis/patología , Células Cultivadas , Hiperplasia/metabolismo , Hiperplasia/patología , Inflamación/metabolismo , Inflamación/patología , Quinasas Asociadas a Receptores de Interleucina-1/química , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Fosforilación , Fosfoserina/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Ubiquitina Tiolesterasa/química , Ubiquitina Tiolesterasa/metabolismo , FN-kappa B/metabolismo , Arterias Carótidas/metabolismo , Arterias Carótidas/patología , Interleucina-1beta/metabolismo , Ubiquitinación
14.
Plant J ; 115(1): 220-235, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36999611

RESUMEN

PROTEIN l-ISOASPARTYL O-METHYLTRANSFERASE (PIMT) affects seed vigor by repairing damaged proteins. While PIMT is capable of isoaspartyl (isoAsp) repair in all proteins, those proteins most susceptible to isoAsp formation have not been well characterized, and the mechanisms by which PIMT affects seed vigor remain largely unknown. Using co-immunoprecipitation and LC-MS/MS, we found that maize (Zea mays) PIMT2 (ZmPIMT2) interacted predominantly with both subunits of maize 3-METHYLCROTONYL COA CARBOXYLASE (ZmMCC). ZmPIMT2 is specifically expressed in the maize embryo. Both mRNA and protein levels of ZmPIMT2 increased during seed maturation and declined during imbibition. Maize seed vigor was decreased in the zmpimt2 mutant line, while overexpression of ZmPIMT2 in maize and Arabidopsis thaliana increased seed vigor upon artificial aging. ZmPIMT2 was localized in the mitochondria, as determined by subcellular localization assays using maize protoplasts. ZmPIMT2 binding to ZmMCCα was confirmed by luciferase complementation tests in both tobacco (Nicotiana benthamiana) leaves and maize protoplasts. Knockdown of ZmMCCα decreased maize seed aging tolerance. Furthermore, overexpression of ZmPIMT2 decreased the accumulation of isoAsp of ZmMCCα protein in seed embryos that underwent accelerated aging treatment. Taken together, our results demonstrate that ZmPIMT2 binds ZmMCCα in mitochondria, repairs isoAsp damage, and positively affects maize seed vigor.


Asunto(s)
Arabidopsis , Zea mays , Zea mays/genética , Cromatografía Liquida , Espectrometría de Masas en Tándem , Arabidopsis/metabolismo , Mitocondrias , Semillas/genética , Semillas/metabolismo
15.
Plant J ; 114(1): 55-67, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36703577

RESUMEN

Drought stress is one of the major constraints of global crop production. Raffinose, a non-reducing trisaccharide, has been considered to regulate positively the plant drought stress tolerance; however, evidence that augmenting raffinose production in leaves results in enhanced plant drought stress tolerance is lacking. The biochemical mechanism through which raffinose might act to mitigate plant drought stress remains unidentified. ZmRAFS encodes Zea mays RAFFINOSE SYNTHASE, a key enzyme that transfers galactose from the galactoside galactinol to sucrose for raffinose production. Overexpression of ZmRAFS in maize increased the RAFS protein and the raffinose content and decreased the water loss of leaves and enhanced plant drought stress tolerance. The biomass of the ZmRAFS overexpressing plants was similar to that of non-transgenic control plants when grown under optimal conditions, but was significantly greater than that of non-transgenic plants when grown under drought stress conditions. In contrast, the percentage of water loss of the detached leaves from two independent zmrafs mutant lines, incapable of synthesizing raffinose, was greater than that from null segregant controls and this phenomenon was partially rescued by supplementation of raffinose to detached zmrafs leaves. In addition, while there were differences in water loss among different maize lines, there was no difference in stomata density or aperture. Taken together, our work demonstrated that overexpression of the ZmRAFS gene in maize, in contrast to Arabidopsis, increased the raffinose content in leaves, assisted the leaf to retain water, and enhanced the plant drought stress tolerance without causing a detectable growth penalty.


Asunto(s)
Arabidopsis , Zea mays , Zea mays/metabolismo , Rafinosa , Resistencia a la Sequía , Arabidopsis/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Sequías , Plantas Modificadas Genéticamente/metabolismo , Agua/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas
16.
Hum Genet ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526745

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with poor prognosis and high mortality. Although a large number of studies have explored its potential prognostic markers using traditional RNA sequencing (RNA-Seq) data, they have not achieved good prediction effect. In order to explore the possible prognostic signaling pathways leading to the difference in prognosis, we identified differentially expressed genes from one scRNA-seq cohort and four GEO cohorts, respectively. Then Cox and Lasso regression analysis showed that 12 genes were independent prognostic factors for PDAC. AUC and calibration curve analysis showed that the prognostic model had good discrimination and calibration. Compared with the low-risk group, the high-risk group had a higher proportion of gene mutations than the low-risk group. Immune infiltration analysis revealed differences in macrophages and monocytes between the two groups. Prognosis related genes were mainly distributed in fibroblasts, macrophages and type 2 ducts. The results of cell communication analysis showed that there was a strong communication between cancer-associated fibroblasts (CAF) and type 2 ductal cells, and collagen formation was the main interaction pathway.

17.
J Gene Med ; 26(1): e3576, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37580111

RESUMEN

BACKGROUND: Adenoviral vectors are among the most frequently used vectors for gene therapy and cancer treatment. Most vectors are derived from human adenovirus (Ad) serotype 5 despite limited applicability caused by pre-existing immunity and unfavorable liver tropism, whereas the other more than 100 known human serotypes remain largely unused. Here, we screened a library of human Ad types and identified Ad4 as a promising candidate vector. METHODS: Reporter-gene-expressing viruses representative of the natural human Ad diversity were used to transduce an array of muscle cell lines and two- or three-dimensional tumor cultures. The time-course of transgene expression was monitored by fluorescence or luminescence measurements. To generate replication-deficient Ad4 vector genomes, successive homologous recombination was applied. RESULTS: Ad4, 17 and 50 transduced human cardiomyocytes more efficiently than Ad5, whereas Ad37 was found to be superior in rhabdomyocytes. Despite its moderate transduction efficiency, Ad4 showed efficient and long-lasting gene expression in papillomavirus (HPV) positive tumor organoids. Therefore, we aimed to harness the potential of Ad4 for improved muscle transduction or oncolytic virotherapy of HPV-positive tumors. We deleted the E1 and E3 transcription units to produce first generation Ad vectors for gene therapy. The E1- and E1/E3-deleted vectors were replication-competent in HEK293 cells stably expressing E1 but not in the other cell lines tested. Furthermore, we show that the Ad5 E1 transcription unit can complement the replication of E1-deleted Ad4 vectors. CONCLUSIONS: Our Ad4-based gene therapy vector platform contributes to the development of improved Ad vectors based on non-canonical serotypes for a broad range of applications.


Asunto(s)
Adenovirus Humanos , Neoplasias , Infecciones por Papillomavirus , Humanos , Serogrupo , Células HEK293 , Adenoviridae/genética , Adenovirus Humanos/genética , Vectores Genéticos/genética , Terapia Genética , Neoplasias/genética , Neoplasias/terapia
18.
Genome Res ; 31(12): 2276-2289, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34503979

RESUMEN

More than 80% of the wheat genome consists of transposable elements (TEs), which act as major drivers of wheat genome evolution. However, their contributions to the regulatory evolution of wheat adaptations remain largely unclear. Here, we created genome-binding maps for 53 transcription factors (TFs) underlying environmental responses by leveraging DAP-seq in Triticum urartu, together with epigenomic profiles. Most TF binding sites (TFBSs) located distally from genes are embedded in TEs, whose functional relevance is supported by purifying selection and active epigenomic features. About 24% of the non-TE TFBSs share significantly high sequence similarity with TE-embedded TFBSs. These non-TE TFBSs have almost no homologous sequences in non-Triticeae species and are potentially derived from Triticeae-specific TEs. The expansion of TE-derived TFBS linked to wheat-specific gene responses, suggesting TEs are an important driving force for regulatory innovations. Altogether, TEs have been significantly and continuously shaping regulatory networks related to wheat genome evolution and adaptation.

19.
Small ; : e2402915, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38845481

RESUMEN

The bismuth anode has garnered significant attention due to its high theoretical Na-storage capacity (386 mAh g-1). There have been numerous research reports on the stable solid electrolyte interphase (SEI) facilitated by electrolytes utilizing ether solvents. In this contribution, cyclic tetrahydrofuran (THF) and 2-methyltetrahydrofuran (MeTHF) ethers are employed as solvents to investigate the sodium-ion storage properties of bismuth anodes. A series of detailed characterizations are utilized to analyze the impact of electrolyte solvation structure and SEI chemical composition on the kinetics of sodium-ion storage. The findings reveal that bismuth anodes in both THF and MeTHF-based electrolytes exhibit exceptional rate performance at low current densities, but in THF-based electrolytes, the reversible capacity is higher at high current densities (316.7 mAh g-1 in THF compared to 9.7 mAh g-1 in MeTHF at 50 A g-1). This stark difference is attributed to the formation of an inorganic-rich, thin, and uniform SEI derived from THF-based electrolyte. Although the SEI derived from MeTHF-based electrolyte also consists predominantly of inorganic components, it is thicker and contains more organic species compared to the THF-derived SEI, impeding charge transfer and ion diffusion. This study offers valuable insights into the utilization of cyclic ether electrolytes for Na-ion batteries.

20.
Ann Rheum Dis ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38777376

RESUMEN

OBJECTIVES: This study aims to evaluate the safety and efficacy of BCMA-CD19 compound chimeric antigen receptor T cells (cCAR) to dual reset the humoral and B cell immune system in patients with systemic lupus erythematosus (SLE) with lupus nephritis (LN). METHODS: This is a single-arm open-label multicentre phase 1 study of BCMA and CD19-directed cCAR in patients suffering from SLE/LN with autoantibodies produced by B cells and plasma/long-lived plasma cells. In this clinical trial, we sequentially assigned biopsy-confirmed (classes III-V) LN patients to receive 3×106 cCAR cells/kg postcessation of all SLE medications and conditioning. The primary endpoint of safety and toxicity was assessed. Complete immune reset was indicated by B cell receptor (BCR) deep sequencing and flow cytometry analysis. Patient 11 (P11) had insufficient lymphocyte counts and was underdosed as compassionate use. RESULTS: P1 and P2 achieved symptom and medication-free remission (MFR) from SLE and complete remission from lymphoma. P3-P13 (excluding P11) received an initial dose of 3×106 cCAR cells /kg and were negative for all autoantibodies, including those derived from long-lived plasma cells, 3 months post-cCAR and the complement returned to normal levels. These patients achieved symptom and MFR with post-cCAR follow-up to 46 months. Complete recovery of B cells was seen in 2-6 months post-cCAR. Mean SLE Disease Activity Index 2000 reduced from 10.6 (baseline) to 2.7 (3 months), and renal function significantly improved in 10 LN patients ≤90 days post-cCAR. cCAR T therapy was well tolerant with mild cytokine-release syndrome. CONCLUSIONS: Data suggest that cCAR therapy was safe and effective in inducing MFR and depleting disease-causing autoantibodies in patients with SLE.

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