RESUMEN

Uracil-DNA glycosylase (UDG) plays a pivotal role in the base repair system. Through bioinformatics, we found that the expression of the UDG enzyme in many cancer cells is increased, and its high expression is not conducive to the prognosis of lung cancer patients. The development of analytical techniques for the quantification of UDG activity and the identification of UDG inhibitors is of paramount importance. We found that when the T base in the G4 loop region mutated to uracil, the G4 structure was not disrupted and still retained the characteristics of a G4 structure (emitting strong fluorescence after binding with ThT (Thioflavin T). Inspired by this phenomenon, we developed a detection method for UDG and its inhibitors utilizing a single DNA strand engineered to form a G-quadruplex structure, containing uracil residues within the loop region, designated as G4-dU. The inclusion of uracil-DNA glycosylase (UDG) in the assay environment induces the removal of uracil, resulting in the formation of apurinic sites (AP) within the G4-dU sequence. Subsequent thermal denaturation leads to strand cleavage at AP sites, precluding the reformation of the G-quadruplex configuration and abrogating fluorescence emission. The detection process in this study can be completed in only 30 min to 1 h, offers a straightforward, expedient, and efficacious modality for assessing UDG activity and UDG inhibitor potency, thereby facilitating the discovery of novel therapeutic agents for cancer treatment.

RESUMEN

The pyrimidine heterocycle plays an important role in anticancer research. In particular, the pyrimidine derivative families of uracil show promise as structural scaffolds relevant to cervical cancer. This group of chemicals lacks data-driven machine learning quantitative structure-activity relationships (QSARs) that allow for generalization and predictive capabilities in the search for new active compounds. To achieve this, a dataset of pyrimidine and uracil compounds from ChEMBL were collected and curated. A workflow was developed for data-driven machine learning QSAR using an intuitive dataset design and forwards selection of molecular descriptors. The model was thoroughly externally validated against available data. Blind validation was also performed by synthesis and antiproliferative evaluation of new synthesized uracil-based and pyrimidine derivatives. The most active compound among new synthesized derivatives, 2,4,5-trisubstituted pyrimidine was predicted with the QSAR model with differences of 0.02 compared to experimentally tested activity.

Asunto(s)

Antineoplásicos , Proliferación Celular , Pirimidinas , Relación Estructura-Actividad Cuantitativa , Uracilo , Uracilo/química , Uracilo/análogos & derivados , Uracilo/farmacología , Uracilo/síntesis química , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Proliferación Celular/efectos de los fármacos , Aprendizaje Automático , Línea Celular Tumoral

RESUMEN

BACKGROUND: The use of adjuvant osimertinib for epidermal growth factor receptor (EGFR) mutants is expected to expand to earlier stage I in the future, potentially competing with the current standard of care, oral tegafur/uracil (UFT), in Japan. However, the effect of EGFR mutation status on the therapeutic effect of UFT remains unclear. This study was conducted as an exploratory analysis of a retrospective observational study that investigated the real-world data of postoperative adjuvant chemotherapy in Japan (CSPOR-LC03). METHODS: Between 2008 and 2013, 1812 patients with completely resected adenocarcinoma diagnosed as pathologic stage I (T1 > 2 cm, TNM classification, sixth edition) who have maintained organ function, and no history of other cancers were included. The primary endpoint was the 5-year disease-free survival (DFS) rate, and we compared this rate between four groups classified based on the administration of adjuvant UFT and EGFR mutation status. RESULTS: Of the 933 (51%) patients with EGFR mutations, 394 underwent adjuvant UFT therapy. Of the 879 (49%) patients without EGFR mutations, 393 underwent adjuvant UFT therapy. The 5-year DFS of UFT+/EGFR+ and UFT-/EGFR+ patients were 82.0 and 87.1%, respectively, and those of UFT+/EGFR- and UFT-/EGFR- patients were 80.0 and 86.9%, respectively. DFS was significantly worse in the UFT+ group than in the UFT- group (P = 0.015). Adjuvant UFT therapy was not an independent prognostic factor for DFS, regardless of the EGFR mutation status. CONCLUSION: In pathologic stage I (>2 cm) lung adenocarcinomas with EGFR mutation, the survival benefit of adjuvant UFT was not observed.

RESUMEN

Excision repair cross-complementation group 2 (ERCC2) encodes the DNA helicase xeroderma pigmentosum group D, which functions in transcription and nucleotide excision repair. Point mutations in ERCC2 are putative drivers in around 10% of bladder cancers (BLCAs) and a potential positive biomarker for cisplatin therapy response. Nevertheless, the prognostic significance directly attributed to ERCC2 mutations and its pathogenic role in genome instability remain poorly understood. We first demonstrated that mutant ERCC2 is an independent predictor of prognosis in BLCA. We then examined its impact on the somatic mutational landscape using a cohort of ERCC2 wild-type (n = 343) and mutant (n = 39) BLCA whole genomes. The genome-wide distribution of somatic mutations is significantly altered in ERCC2 mutants, including T[C>T]N enrichment, altered replication time correlations, and CTCF-cohesin binding site mutation hotspots. We leverage these alterations to develop a machine learning model for predicting pathogenic ERCC2 mutations, which may be useful to inform treatment of patients with BLCA.

Asunto(s)

Mutación , Neoplasias de la Vejiga Urinaria , Proteína de la Xerodermia Pigmentosa del Grupo D , Humanos , Neoplasias de la Vejiga Urinaria/genética , Proteína de la Xerodermia Pigmentosa del Grupo D/genética , Pronóstico

RESUMEN

Uracil-DNA glycosylase (UDG), an enzyme for repairing uracil-containing DNA damage, is crucial for maintaining genomic stability. Simple and fast quantification of UDG activity is essential for biological assay and clinical diagnosis, since its aberrant level is associated with DNA damage and various diseases. Herein, we developed a fully integrated "sample in-signal out" distance-based paper analytical device (dPAD) for visual quantification of UDG using a flow-controlled uracil-rich DNA hydrogel (URDH). The uracil base sites contained in the DNA hydrogel are mis-incorporated with dUTP by rolling circle amplification (RCA), which simplifies the preparation process of the functionalized hydrogel. In the presence of UDG, the uracil in URDH can be recognized and removed to induce the permeability change of URDH, resulting in the visible distance signal along the paper channel. Using dPAD, as low as 6.4 × 10-4 U/mL of UDG (within 80 min) is visually identified without any instruments and complicated operations. This integrated dPAD is advantageous for its simplicity, cost effectiveness, and ease of use. We envision that it has the great potential for point-of-care testing (POCT) in DNA damage testing, personalized healthcare assessment, and biomedical applications.

Asunto(s)

Técnicas Biosensibles , ADN , Hidrogeles , Papel , Uracil-ADN Glicosidasa , Uracilo , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Humanos , ADN/química , Uracilo/química , Hidrogeles/química , Diseño de Equipo , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Técnicas de Amplificación de Ácido Nucleico/métodos , Límite de Detección , Daño del ADN

RESUMEN

The formation and characterization of new diamagnetic ruthenium uracil mono-imine compounds: [(η6-p-cymene)RuII(L)Cl][BF4] (L = H2urpda = 5-((pyridin-2-yl)methyleneamino)-6-aminouracil) for 1, urdpy = 6-amino-1,3-dimethyl-5-((pyridin-2-ylmethylene)amino)uracil) for 2 or urqda = 5-((quinolin-2-yl)methyleneamino)-6-aminouracil) for 3); cis-[RuII(L)(bipy)2] (L =  urpy = 5-((pyridin-2-yl)methyleneamino)uracil) for 4 and H2dadp = 5,6-diaminouracil for 5) are described. A paramagnetic ruthenium uracil Schiff base compound,  trans-[RuIV(L)(PPh3)Cl2] (L = H2urpda for 6) was also formed. Various physicochemical techniques were utilized to characterize the novel ruthenium compounds. Similarly, the stabilities of 1 - 3 and 6 monitored in chloro-containing and the non-coordinating solvent, dichloromethane show that they are kinetically inert, whereas, in a high nucleophilic environment, the chloride co-ligands of these ruthenium complexes were rapidly substituted by DMSO. In contrast, the substitution of the labile co-ligands for these ruthenium complexes by DMSO molecules in a high chloride content was suppressed. Solution chemical reactivities of the different ruthenium complexes were rationalized by density functional theory computations. Furthermore, the binding affinities and strengths between BSA and the respective ruthenium complexes were monitored using fluorescence spectroscopy. In addition, the in vitro anti-diabetic activities of the novel metal complexes were assessed in selected skeletal muscle and liver cell lines.

RESUMEN

Human APOBEC single-strand (ss) specific DNA and RNA cytidine deaminases change cytosines to uracils and function in antiviral innate immunity, RNA editing, and can cause hypermutation in chromosomes. The resulting uracils can be directly replicated, resulting in C to T mutations, or uracil-DNA glycosylase can convert the uracils to abasic (AP) sites which are then fixed as C to T or C to G mutations by translesion DNA polymerases. We noticed that in yeast and in human cancers, contributions of C to T and C to G mutations depends on the origin of ssDNA mutagenized by APOBECs. Since ssDNA in eukaryotic genomes readily binds to replication protein A (RPA) we asked if RPA could affect APOBEC-induced mutation spectrum in yeast. For that purpose, we expressed human APOBECs in the wild-type yeast and in strains carrying a hypomorph mutation rfa1-t33 in the large RPA subunit. We confirmed that the rfa1-t33 allele can facilitate mutagenesis by APOBECs. We also found that the rfa1-t33 mutation changed the ratio of APOBEC3A-induced T to C and T to G mutations in replicating yeast to resemble a ratio observed in long-persistent ssDNA in yeast and in cancers. We present the data suggesting that RPA may shield APOBEC formed uracils in ssDNA from Ung1, thereby facilitating C to T mutagenesis through the accurate copying of uracils by replicative DNA polymerases. Unexpectedly, we also found that for uracils shielded from Ung1 by wild-type RPA the mutagenic outcome is reduced in the presence of translesion DNA polymerase zeta.

RESUMEN

The generation of DNA damage causes mutations and consequently cancer. Reactive oxygen species are important sources of DNA damage and some mutation signatures found in human cancers. 8-Oxo-7,8-dihydroguanine (GO, 8-hydroxyguanine) is one of the most abundant oxidized bases and induces a G→T transversion mutation at the modified site. The damaged G base also causes untargeted base substitution mutations at the G bases of 5'-GpA-3' dinucleotides (action-at-a-distance mutations) in human cells, and the cytosine deaminase apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3 (APOBEC3) is involved in the mutation process. The deaminated cytosine, i.e., uracil, bases are expected to be removed by uracil DNA glycosylase. Most of the substitution mutations at the G bases of 5'-GpA-3' might be caused by abasic sites formed by the glycosylase. In this study, we expressed the uracil DNA glycosylase inhibitor from Bacillus subtilis bacteriophage PBS2 in human U2OS cells and examined the effects on the GO-induced action-at-a-distance mutations. The inhibition of uracil DNA glycosylase increased the mutation frequency, and in particular, the frequency of G→A transitions. These results indicated that uracil DNA glycosylase, in addition to APOBEC3, is involved in the untargeted mutation process induced by GO.

Asunto(s)

Guanina , Mutación , Uracil-ADN Glicosidasa , Humanos , Guanina/análogos & derivados , Guanina/metabolismo , Uracil-ADN Glicosidasa/metabolismo , Uracil-ADN Glicosidasa/genética , Línea Celular Tumoral , Daño del ADN , Bacillus subtilis/genética , Bacteriófagos/genética

RESUMEN

DNA glycosylases are a group of enzymes that play a crucial role in the DNA repair process by recognizing and removing damaged or incorrect bases from DNA molecules, which maintains the integrity of the genetic information. The abnormal expression of uracil-DNA glycosylase (UDG), one of significant DNA glycosylases in the base-excision repair pathway, is linked to numerous diseases. Here, we proposed a simple UDG activity detection method based on toehold region triggered CRISPR/Cas12a trans-cleavage. The toehold region on hairpin DNA probe (HP) produced by UDG could induce the trans-cleavage of ssDNA with fluorophore and quencher, generating an obvious fluorescence signal. This protospacer adjacent motif (PAM)-free approach achieves remarkable sensitivity and specificity in detecting UDG, with a detection limit as low as 0.000368 U mL-1. Moreover, this method is able to screen inhibitors and measure UDG in complex biological samples. These advantages render it highly promising for applications in clinical diagnosis and drug discovery.

Asunto(s)

Sistemas CRISPR-Cas , Uracil-ADN Glicosidasa , Uracil-ADN Glicosidasa/metabolismo , Uracil-ADN Glicosidasa/genética , Sistemas CRISPR-Cas/genética , Humanos , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Asociadas a CRISPR/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ADN de Cadena Simple/metabolismo , ADN de Cadena Simple/genética

RESUMEN

Human APOBEC single-strand (ss) specific DNA and RNA cytidine deaminases change cytosines to uracils and function in antiviral innate immunity, RNA editing, and can cause hypermutation in chromosomes. The resulting uracils can be directly replicated, resulting in C to T mutations, or uracil-DNA glycosylase can convert the uracils to abasic (AP) sites which are then fixed as C to T or C to G mutations by translesion DNA polymerases. We noticed that in yeast and in human cancers, contributions of C to T and C to G mutations depends on the origin of ssDNA mutagenized by APOBECs. Since ssDNA in eukaryotic genomes readily binds to replication protein A (RPA) we asked if RPA could affect APOBEC-induced mutation spectrum in yeast. For that purpose, we expressed human APOBECs in the wild-type yeast and in strains carrying a hypomorph mutation rfa1-t33 in the large RPA subunit. We confirmed that the rfa1-t33 allele can facilitate mutagenesis by APOBECs. We also found that the rfa1-t33 mutation changed the ratio of APOBEC3A-induced T to C and T to G mutations in replicating yeast to resemble a ratio observed in long-persistent ssDNA in yeast and in cancers. We present the data suggesting that RPA may shield APOBEC formed uracils in ssDNA from Ung1, thereby facilitating C to T mutagenesis through the accurate copying of uracils by replicative DNA polymerases. Unexpectedly, we also found that for uracils shielded from Ung1 by wild-type RPA the mutagenic outcome is reduced in the presence of translesion DNA polymerase zeta.

RESUMEN

OBJECTIVES: Dihydropyrimidinase deficiency is a rare autosomal recessive disorder of the pyrimidine degradation pathway, with fewer than 40 patients published. Clinical findings are variable and some patients may remain asymptomatic. Global developmental delay and increased susceptibility to 5-fluorouracil are commonly reported. Here we present atrioventricular septal defect as a novel feature in dihydropyrimidinase deficiency. CASE PRESENTATION: A four-year-old male with global developmental delay, dysmorphic facies, autistic features and a history of seizures was diagnosed with dihydropyrimidinase deficiency based on strikingly elevated urinary dihydrouracil and dihydrothymine and a homozygous pathogenic nonsense variant in DPYS gene. He had a history of complete atrioventricular septal defect corrected surgically in infancy. CONCLUSIONS: This is the second report of congenital heart disease in dihydropyrimidinase deficiency, following a single patient with a ventricular septal defect. The rarity of the disease and the variability of the reported findings make it difficult to describe a disease-specific clinical phenotype. The mechanism of neurological and other systemic findings is unclear. Dihydropyrimidinase deficiency should be considered in patients with microcephaly, developmental delay, epilepsy and autistic traits. We suggest that congenital heart disease may also be a rare phenotypic feature.

Asunto(s)

Deficiencia de Dihidropirimidina Deshidrogenasa , Defectos de los Tabiques Cardíacos , Humanos , Masculino , Preescolar , Defectos de los Tabiques Cardíacos/genética , Deficiencia de Dihidropirimidina Deshidrogenasa/complicaciones , Deficiencia de Dihidropirimidina Deshidrogenasa/genética , Pronóstico , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/etiología , Discapacidades del Desarrollo/patología , Amidohidrolasas

RESUMEN

Real-time PCR with intercalating dyes can only be performed once. The expensive fluorescent hydrolysis probes are target specific and are suitable to detect multiplex targets. Uracil-DNA N-glycosylase (UNG), which specifically hydrolyzes and degrades any uracil-containing PCR products, is often applied before PCR to reduce carryover contamination. We developed an optimized protocol for recovering DNA from PCR products and revaluating by real-time PCR with intercalating dye using UNG processing, which is particularly useful when the sample volume is very small and insufficient for multiple assays of real-time PCR.•A real-time PCR master mix with dUTP instead of dTTP was used.•UNG at 1 % and 10 % concentrations of PCR product volumes were used for the first and second processing.•The second real-time PCR was performed with different primer pairs than the first real-time PCR.

RESUMEN

Fluorouracil is among the most used antimetabolite drugs for the chemotherapeutic treatment of various types of gastrointestinal malignancies. Dihydropyrimidine dehydrogenase (DPYD) genotyping prior to fluorouracil treatment is considered standard practice in most European countries. Yet, current pre-therapeutic DPYD genotyping procedures do not identify all dihydropyrimidine dehydrogenase (DPD)-deficient patients. Alternatively, DPD activity can be estimated by determining the DPD phenotype by quantification of plasma concentrations of the endogenous uracil and thymine concentrations and their respective metabolites dihydrouracil (DHU) and dihydrothymine (DHT). Liquid chromatography - mass spectrometry (LC-MS) detection is currently considered as the most adequate method for quantification of low-molecular weight molecules, although the sample preparation method is highly critical for analytical outcome. It was hypothesized that during protein precipitation, the recovery of the molecule of interest highly depends on the choice of precipitation agent and the extent of protein binding in plasma. In this work, the effect of protein precipitation using acetonitrile (ACN) compared to strong acid perchloric acid (PCA) on the recovery of uracil, thymine, DHU and DHT is demonstrated. Upon the analysis of plasma samples, PCA precipitation showed higher concentrations of uracil and thymine as compared to ACN precipitation. Using ultrafiltration, it was shown that uracil and thymine are significantly (60-65 %) bound to proteins compared to DHU and DHT. This shows that before harmonized cut-off levels of DPD phenotyping can be applied in clinical practice, the analytical methodology requires extensive further optimization.

Asunto(s)

Dihidrouracilo Deshidrogenasa (NADP) , Fenotipo , Unión Proteica , Timina , Uracilo , Timina/metabolismo , Uracilo/análogos & derivados , Uracilo/metabolismo , Uracilo/sangre , Dihidrouracilo Deshidrogenasa (NADP)/metabolismo , Dihidrouracilo Deshidrogenasa (NADP)/genética , Humanos , Cromatografía Liquida/métodos , Fluorouracilo/metabolismo , Fluorouracilo/sangre , Genotipo , Deficiencia de Dihidropirimidina Deshidrogenasa/metabolismo , Espectrometría de Masas en Tándem/métodos

RESUMEN

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide. Significantly activated uridine nucleotide and fatty acid metabolism in HCC cells promote malignant proliferation and immune evasion. Herein, it is demonstrated that the tripartite motif 65 (TRIM65) E3 ubiquitin-protein ligase, O-GlcNAcylated via O-GlcNAcylation transferase, is highly expressed in HCC and facilitated metabolic remodeling to promote the accumulation of products related to uracil metabolism and palmitic acid, driving the progression of HCC. Mechanistically, it is showed that TRIM65 mediates ubiquitylation at the K44 residue of neurofibromatosis type 2 (NF2), the key protein upstream of classical Hippo signaling. Accelerated NF2 degradation inhibits yes-associated protein 1 phosphorylation, inducing aberrant activation of related metabolic enzyme transcription, and orchestrating metabolic and immune advantages. In conclusion, these results reveal a critical role for the TRIM family molecule TRIM65 in supporting HCC cell survival and highlight the therapeutic potential of targeting its E3 ligase activity to alter the regulation of proteasomal degradation.

RESUMEN

Determination of plasma uracil was reported as a method for evaluation of Dihydropyrimidine dehydrogenase (DPD) activity that is highly demanded to ensure the safe administration of 5-fluorouracil (5-FU)-based therapies to cancer patients. This work reports the development of a simple electroanalytical method based on adsorptive stripping square wave voltammetry (AdSWV) at mercury film-coated glassy carbon electrode (MF/GCE) for the highly sensitive determination of uracil in biological fluids that can be used for diagnosis of decreased DPD activity. Due to the formation of the HgII-Uracil complex at the electrode surface, the accuracy of the measurement was not affected by the complicated matrices in biological fluids including human serum, plasma, and urine. The high sensitivity of the developed method results in a low limit of detection (≈1.3 nM) in human plasma samples, falling below the practical cut-off level of 15 ng mL-1 (≈0.14 µM). This threshold concentration is crucial for predicting 5-FU toxicity, as reported in buffer, and ≤1.15% in biological samples), and accuracy (recovery percentage close to 100%).

Asunto(s)

Técnicas Biosensibles , Deficiencia de Dihidropirimidina Deshidrogenasa , Electrodos , Fluorouracilo , Mercurio , Uracilo , Humanos , Uracilo/sangre , Mercurio/sangre , Límite de Detección , Técnicas Electroquímicas/métodos , Dihidrouracilo Deshidrogenasa (NADP)/metabolismo

RESUMEN

BACKGROUND: The efficacy of adjuvant chemotherapy for high-risk stage II colon cancer (CC) has not been well established. Using propensity score matching, we previously reported that the 3-year disease-free survival (DFS) rate was significantly higher in patients treated with uracil and tegafur plus leucovorin (UFT/LV) against surgery alone. We report the final results, including updated 5-year overall survival (OS) rates and risk factor analysis outcomes. METHODS: In total, 1902 high-risk stage II CC patients with T4, perforation/penetration, poorly differentiated adenocarcinoma/mucinous carcinoma, and/or < 12 dissected lymph nodes were enrolled in this prospective, non-randomized controlled study based on their self-selected treatment. Oral UFT/LV therapy was administered for six months after surgery. RESULTS: Of the 1880 eligible patients, 402 in Group A (surgery alone) and 804 in Group B (UFT/LV) were propensity score-matched. The 5-year DFS rate was significantly higher in Group B than in Group A (P = 0.0008). The 5-year OS rates were not significantly different between groups. The inverse probability of treatment weighting revealed significantly higher 5-year DFS (P = 0.0006) and 5-year OS (P = 0.0122) rates in group B than in group A. Multivariate analyses revealed that male sex, age ≥ 70 years, T4, < 12 dissected lymph nodes, and no adjuvant chemotherapy were significant risk factors for DFS and/or OS. CONCLUSION: The follow-up data from our prospective non-randomized controlled study revealed a considerable survival advantage in DFS offered by adjuvant chemotherapy with UFT/LV administered for six months over surgery alone in individuals with high-risk stage II CC. TRIAL REGISTRATION: Japan Registry of Clinical Trials: jRCTs031180155 (date of registration: 25/02/2019), UMIN Clinical Trials Registry: UMIN000007783 (date of registration: 18/04/2012).

Asunto(s)

Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias del Colon , Leucovorina , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Puntaje de Propensión , Tegafur , Uracilo , Humanos , Tegafur/administración & dosificación , Tegafur/uso terapéutico , Masculino , Femenino , Anciano , Uracilo/administración & dosificación , Uracilo/uso terapéutico , Persona de Mediana Edad , Leucovorina/uso terapéutico , Leucovorina/administración & dosificación , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Estudios Prospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Factores de Riesgo , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Supervivencia sin Enfermedad , Anciano de 80 o más Años

RESUMEN

OBJECTIVES: Dihydropyrimidine dehydrogenase (DPD) deficiency is the main cause of severe fluoropyrimidine-related toxicities. The best strategy for identifying DPD-deficient patients is still not defined. The EMA recommends targeted DPYD genotyping or uracilemia (U) testing. We analyzed the concordance between both approaches. METHODS: This study included 19,376 consecutive French patients with pre-treatment plasma U, UH2 and targeted DPYD genotyping (*2A, *13, D949V, *7) analyzed at Eurofins Biomnis (2015-2022). RESULTS: Mean U was 9.9 ± 10.1 ng/mL (median 8.7, range 1.6-856). According to French recommendations, 7.3 % of patients were partially deficient (U 16-150 ng/mL) and 0.02 % completely deficient (U≥150 ng/mL). DPYD variant frequencies were *2A: 0.83 %, *13: 0.17 %, D949V: 1.16 %, *7: 0.05 % (2 homozygous patients with U at 22 and 856 ng/mL). Variant carriers exhibited higher U (median 13.8 vs. 8.6 ng/mL), and lower UH2/U (median 7.2 vs. 11.8) and UH2/U2 (median 0.54 vs. 1.37) relative to wild-type patients (p<0.00001). Sixty-six% of variant carriers exhibited uracilemia <16 ng/mL, challenging correct identification of DPD deficiency based on U. The sensitivity (% patients with a deficient phenotype among variant carriers) of U threshold at 16 ng/mL was 34 %. The best discriminant marker for identifying variant carriers was UH2/U2. UH2/U2<0.942 (29.7 % of patients) showed enhanced sensitivity (81 %) in identifying deleterious genotypes across different variants compared to 16 ng/mL U. CONCLUSIONS: These results reaffirm the poor concordance between DPD phenotyping and genotyping, suggesting that both approaches may be complementary and that targeted DPYD genotyping is not sufficiently reliable to identify all patients with complete deficiency.

RESUMEN

In the structure of the title complex, [Zn(C4H2FN2O2)(C10H24N4)]ClO4, the zinc(II) ion forms coordination bonds with the four nitro-gen atoms of cyclam (1,4,8,11-tetra-aza-cyclo-tetra-decane or [14]aneN4) as well as with the nitro-gen atom of a deprotonated 5-fluoro-uracil ion (FU-). Cyclam adopts a trans-I type conformation within this structure. The coordination structure of the zinc(II) ion is a square pyramid with a distorted base plane formed by the four nitro-gen atoms of the cyclam. FU- engages in inter-molecular hydrogen bonding with neighboring FU- mol-ecules and with the cyclam mol-ecule.

RESUMEN

Fusarium verticillioides (F. verticillioides) is a globally recognized and highly impactful fungal pathogen of maize, causing yield losses and producing harmful mycotoxins that pose a threat to human and animal health. However, the genetic tools available for studying this crucial fungus are currently limited in comparison to other important fungal pathogens. To address this, an efficient CRISPR/Cas9 genome editing system based on an autonomously replicating plasmid with an AMA1 sequence was established in this study. First, gene disruption of pyrG and pyrE via nonhomologous end-joining (NHEJ) pathway was successfully achieved, with efficiency ranging from 66 to 100%. Second, precise gene deletions were achieved with remarkable efficiency using a dual sgRNA expression strategy. Third, the developed genome editing system can be applied to generate designer chromosomes in F. verticillioides, as evidenced by the deletion of a crucial 38 kb fragment required for fumonisin biosynthesis. Fourth, the pyrG recycling system has been established and successfully applied in F. verticillioides. Lastly, the developed ΔFUM1 and ΔFUM mutants can serve as biocontrol agents to reduce the fumonisin B1 (FB1) contamination produced by the toxigenic strain. Taken together, these significant advancements in genetic manipulation and biocontrol strategies provide valuable tools for studying and mitigating the impact of F. verticillioides on maize crops.

Asunto(s)

Sistemas CRISPR-Cas , Proteínas Fúngicas , Fusarium , Edición Génica , Micotoxinas , Zea mays , Fusarium/genética , Fusarium/metabolismo , Edición Génica/métodos , Zea mays/microbiología , Micotoxinas/metabolismo , Micotoxinas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Fumonisinas/metabolismo , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control