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1.
Nature ; 618(7966): 799-807, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37316670

RESUMEN

Plants deploy receptor-like kinases and nucleotide-binding leucine-rich repeat receptors to confer host plant resistance (HPR) to herbivores1. These gene-for-gene interactions between insects and their hosts have been proposed for more than 50 years2. However, the molecular and cellular mechanisms that underlie HPR have been elusive, as the identity and sensing mechanisms of insect avirulence effectors have remained unknown. Here we identify an insect salivary protein perceived by a plant immune receptor. The BPH14-interacting salivary protein (BISP) from the brown planthopper (Nilaparvata lugens Stål) is secreted into rice (Oryza sativa) during feeding. In susceptible plants, BISP targets O. satvia RLCK185 (OsRLCK185; hereafter Os is used to denote O. satvia-related proteins or genes) to suppress basal defences. In resistant plants, the nucleotide-binding leucine-rich repeat receptor BPH14 directly binds BISP to activate HPR. Constitutive activation of Bph14-mediated immunity is detrimental to plant growth and productivity. The fine-tuning of Bph14-mediated HPR is achieved through direct binding of BISP and BPH14 to the selective autophagy cargo receptor OsNBR1, which delivers BISP to OsATG8 for degradation. Autophagy therefore controls BISP levels. In Bph14 plants, autophagy restores cellular homeostasis by downregulating HPR when feeding by brown planthoppers ceases. We identify an insect saliva protein sensed by a plant immune receptor and discover a three-way interaction system that offers opportunities for developing high-yield, insect-resistant crops.


Asunto(s)
Hemípteros , Proteínas de Insectos , Oryza , Defensa de la Planta contra la Herbivoria , Proteínas de Plantas , Animales , Hemípteros/inmunología , Hemípteros/fisiología , Leucina/metabolismo , Nucleótidos/metabolismo , Oryza/crecimiento & desarrollo , Oryza/inmunología , Oryza/metabolismo , Oryza/fisiología , Defensa de la Planta contra la Herbivoria/inmunología , Defensa de la Planta contra la Herbivoria/fisiología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Proteínas de Insectos/metabolismo , Autofagia
2.
EMBO J ; 42(17): e113415, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37485728

RESUMEN

The human ABC transporter ABCC3 (also known as MRP3) transports a wide spectrum of substrates, including endogenous metabolites and exogenous drugs. Accordingly, it participates in multiple physiological processes and is involved in diverse human diseases such as intrahepatic cholestasis of pregnancy, which is caused by the intracellular accumulation of bile acids and estrogens. Here, we report three cryogenic electron microscopy structures of ABCC3: in the apo-form and in complexed forms bound to either the conjugated sex hormones ß-estradiol 17-(ß-D-glucuronide) and dehydroepiandrosterone sulfate. For both hormones, the steroid nuclei that superimpose against each other occupy the hydrophobic center of the transport cavity, whereas the two conjugation groups are separated and fixed by the hydrophilic patches in two transmembrane domains. Structural analysis combined with site-directed mutagenesis and ATPase activity assays revealed that ABCC3 possesses an amphiphilic substrate-binding pocket able to hold either conjugated hormone in an asymmetric pattern. These data build on consensus features of the substrate-binding pocket of MRPs and provide a structural platform for the rational design of inhibitors.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Estradiol , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Estradiol/farmacología , Estradiol/metabolismo , Mutagénesis Sitio-Dirigida
3.
Proc Natl Acad Sci U S A ; 121(11): e2318320121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38457518

RESUMEN

Coordinated carbon and nitrogen metabolism is crucial for bacteria living in the fluctuating environments. Intracellular carbon and nitrogen homeostasis is maintained by a sophisticated network, in which the widespread signaling protein PII acts as a major regulatory hub. In cyanobacteria, PII was proposed to regulate the nitrate uptake by an ABC (ATP-binding cassette)-type nitrate transporter NrtABCD, in which the nucleotide-binding domain of NrtC is fused with a C-terminal regulatory domain (CRD). Here, we solved three cryoelectron microscopy structures of NrtBCD, bound to nitrate, ATP, and PII, respectively. Structural and biochemical analyses enable us to identify the key residues that form a hydrophobic and a hydrophilic cavity along the substrate translocation channel. The core structure of PII, but not the canonical T-loop, binds to NrtC and stabilizes the CRD, making it visible in the complex structure, narrows the substrate translocation channel in NrtB, and ultimately locks NrtBCD at an inhibited inward-facing conformation. Based on these results and previous reports, we propose a putative transport cycle driven by NrtABCD, which is allosterically inhibited by PII in response to the cellular level of 2-oxoglutarate. Our findings provide a distinct regulatory mechanism of ABC transporter via asymmetrically binding to a signaling protein.


Asunto(s)
Cianobacterias , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas Bacterianas/metabolismo , Regulación Alostérica , Microscopía por Crioelectrón , Cianobacterias/metabolismo , Adenosina Trifosfato/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Proteínas PII Reguladoras del Nitrógeno/genética , Proteínas PII Reguladoras del Nitrógeno/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(4): e2213727120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36656854

RESUMEN

The myophage possesses a contractile tail that penetrates its host cell envelope. Except for investigations on the bacteriophage T4 with a rather complicated structure, the assembly pattern and tail contraction mechanism of myophage remain largely unknown. Here, we present the fine structure of a freshwater Myoviridae cyanophage Pam3, which has an icosahedral capsid of ~680 Å in diameter, connected via a three-section neck to an 840-Å-long contractile tail, ending with a three-module baseplate composed of only six protein components. This simplified baseplate consists of a central hub-spike surrounded by six wedge heterotriplexes, to which twelve tail fibers are covalently attached via disulfide bonds in alternating upward and downward configurations. In vitro reduction assays revealed a putative redox-dependent mechanism of baseplate assembly and tail sheath contraction. These findings establish a minimal myophage that might become a user-friendly chassis phage in synthetic biology.


Asunto(s)
Myoviridae , Ensamble de Virus , Bacteriófago T4/química , Cápside , Proteínas de la Cápside/química , Microscopía por Crioelectrón , Myoviridae/química
5.
Nucleic Acids Res ; 51(D1): D593-D602, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36243971

RESUMEN

Metalloenzymes are attractive research targets in fields of chemistry, biology, and medicine. Given that metalloenzymes can manifest conservation of metal-coordination and ligand binding modes, the excavation and expansion of metalloenzyme-specific knowledge is of interest in bridging metalloenzyme-related fields. Building on our previous metalloenzyme-ligand association database, MeLAD, we have expanded the scope of metalloenzyme-specific knowledge and services, by forming a versatile platform, termed the Metalloenzyme Data Bank and Analysis (MeDBA). The MeDBA provides: (i) manual curation of metalloenzymes into different categories, that this M-I, M-II and M-III; (ii) comprehensive information on metalloenzyme activities, expression profiles, family and disease links; (iii) structural information on metalloenzymes, in particular metal binding modes; (iv) metalloenzyme substrates and bioactive molecules acting on metalloenzymes; (v) excavated metal-binding pharmacophores and (vi) analysis tools for structure/metal active site comparison and metalloenzyme profiling. The MeDBA is freely available at https://medba.ddtmlab.org.


Asunto(s)
Bases de Datos de Proteínas , Metaloproteínas , Dominio Catalítico , Ligandos , Metaloproteínas/metabolismo , Metales , Enzimas
6.
Nucleic Acids Res ; 51(D1): D57-D69, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36243984

RESUMEN

Chromatin loops (or chromatin interactions) are important elements of chromatin structures. Disruption of chromatin loops is associated with many diseases, such as cancer and polydactyly. A few methods, including ChIA-PET, HiChIP and PLAC-Seq, have been proposed to detect high-resolution, specific protein-mediated chromatin loops. With rapid progress in 3D genomic research, ChIA-PET, HiChIP and PLAC-Seq datasets continue to accumulate, and effective collection and processing for these datasets are urgently needed. Here, we developed a comprehensive, multispecies and specific protein-mediated chromatin loop database (ChromLoops, https://3dgenomics.hzau.edu.cn/chromloops), which integrated 1030 ChIA-PET, HiChIP and PLAC-Seq datasets from 13 species, and documented 1 491 416 813 high-quality chromatin loops. We annotated genes and regions overlapping with chromatin loop anchors with rich functional annotations, such as regulatory elements (enhancers, super-enhancers and silencers), variations (common SNPs, somatic SNPs and eQTLs), and transcription factor binding sites. Moreover, we identified genes with high-frequency chromatin interactions in the collected species. In particular, we identified genes with high-frequency interactions in cancer samples. We hope that ChromLoops will provide a new platform for studying chromatin interaction regulation in relation to biological processes and disease.


Asunto(s)
Cromatina , Bases de Datos Genéticas , Cromatina/genética , Cromosomas , Genoma , Genómica , Secuencias Reguladoras de Ácidos Nucleicos , Humanos , Animales
7.
Proc Natl Acad Sci U S A ; 119(14): e2118656119, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35349344

RESUMEN

SignificanceATP8B1 is a P4 ATPase that maintains membrane asymmetry by transporting phospholipids across the cell membrane. Disturbance of lipid asymmetry will lead to the imbalance of the cell membrane and eventually, cell death. Thus, defects in ATP8B1 are usually associated with severe human diseases, such as intrahepatic cholestasis. The present structures of ATP8B1 complexed with its auxiliary noncatalytic partners CDC50A and CDC50B reveal an autoinhibited state of ATP8B1 that could be released upon substrate binding. Moreover, release of this autoinhibition could be facilitated by the bile acids, which are key factors that alter the membrane asymmetry of hepatocytes. This enabled us to figure out a feedback loop of bile acids and lipids across the cell membrane.


Asunto(s)
Adenosina Trifosfatasas , Colestasis Intrahepática , Adenosina Trifosfatasas/metabolismo , Ácidos y Sales Biliares/metabolismo , Membrana Celular/metabolismo , Colestasis Intrahepática/metabolismo , Humanos , Proteínas de Transferencia de Fosfolípidos/metabolismo , Fosfolípidos/metabolismo
8.
Nano Lett ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848333

RESUMEN

The intricate interplay between light and matter provides effective tools for manipulating topological phenomena. Here, we theoretically propose and computationally show that circularly polarized light holds the potential to transform the axion insulating phase into a quantum anomalous Hall state in MnBi2Te4 thin films, featuring tunable Chern numbers (ranging up to ±2). In particular, we reveal the spatial rearrangement of the hidden layer-resolved anomalous Hall effect under light-driven Floquet engineering. Notably, upon Bi2Te3 layer intercalation, the anomalous Hall conductance predominantly localizes in the nonmagnetic Bi2Te3 layers that hold zero Berry curvature in the intact state, suggesting a significant magnetic proximity effect. Additionally, we estimate variations in the magneto-optical Kerr effect, giving a contactless method for detecting topological transitions. Our work not only presents a strategy to investigate emergent topological phases but also sheds light on the possible applications of the layer Hall effect in topological antiferromagnetic spintronics.

9.
J Cell Physiol ; 239(5): e31213, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38308641

RESUMEN

Recent studies have shown that nucleophagy can mitigate DNA damage by selectively degrading nuclear components protruding from the nucleus. However, little is known about the role of nucleophagy in neurons after spinal cord injury (SCI). Western blot analysis and immunofluorescence were performed to evaluate the nucleophagy after nuclear DNA damage and leakage in SCI neurons in vivo and NSC34 expression in primary neurons cultured with oxygen-glucose deprivation (OGD) in vitro, as well as the interaction and colocalization of autophagy protein LC3 with nuclear lamina protein Lamin B1. The effect of UBC9, a Small ubiquitin-related modifier (SUMO) E2 ligase, on Lamin B1 SUMOylation and nucleophagy was examined by siRNA transfection or 2-D08 (a small-molecule inhibitor of UBC9), immunoprecipitation, and immunofluorescence. In SCI and OGD injured NSC34 or primary cultured neurons, neuronal nuclear DNA damage induced the SUMOylation of Lamin B1, which was required by the nuclear Lamina accumulation of UBC9. Furthermore, LC3/Atg8, an autophagy-related protein, directly bound to SUMOylated Lamin B1, and delivered Lamin B1 to the lysosome. Knockdown or suppression of UBC9 with siRNA or 2-D08 inhibited SUMOylation of Lamin B1 and subsequent nucleophagy and protected against neuronal death. Upon neuronal DNA damage and leakage after SCI, SUMOylation of Lamin B1 is induced by nuclear Lamina accumulation of UBC9. Furthermore, it promotes LC3-Lamin B1 interaction to trigger nucleophagy that protects against neuronal DNA damage.


Asunto(s)
Autofagia , Daño del ADN , Lamina Tipo B , Neuronas , Traumatismos de la Médula Espinal , Sumoilación , Enzimas Ubiquitina-Conjugadoras , Animales , Ratones , Núcleo Celular/metabolismo , Lamina Tipo B/metabolismo , Lamina Tipo B/genética , Neuronas/metabolismo , Neuronas/patología , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/patología , Enzimas Ubiquitina-Conjugadoras/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Ratones Endogámicos C57BL , Línea Celular Tumoral
10.
J Am Chem Soc ; 146(3): 1984-1991, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38113828

RESUMEN

Asymmetric electrocatalysis offers exciting new strategies for the synthesis of chiral molecules through novel reaction pathways. However, simultaneous activation of reactants on both electrodes via asymmetric paired electrolysis, which is more energy efficient and economic than single half-electrode synthesis, remains a formidable challenge. Herein, an asymmetric olefin-sulfonylimine coupling via paired electrocatalysis is presented for the first time. In this protocol, Co-catalyzed hydrogen atom transfer on the anode and Ni-catalyzed sulfonylimine reduction on the cathode were seamlessly cross-coupled. The new catalytic system enables the formation of chiral amine products bearing a tetrasubstituted carbon stereocenter with a high enantioselectivity (up to 96% ee).

11.
Chemistry ; 30(44): e202401371, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38825569

RESUMEN

Herein, we describe a visible light-induced C(sp2)-H arylation method for quinoxalin-2(1H)-ones and coumarins using iodonium ylides without the need for external photocatalysts. The protocol demonstrates a broad substrate scope, enabling the arylation of diverse heterocycles through a simple and mild procedure. Furthermore, the photochemical reaction showcases its applicability in the efficient synthesis of biologically active molecules. Computational investigations at the CASPT2//CASSCF/PCM level of theory revealed that the excited state of quinoxalin-2(1H)-one facilitates electron transfer from its π bond to the antibonding orbital of the C-I bond in the iodonium ylide, ultimately leading to the formation of an aryl radical, which subsequently participates in the C-H arylation process. In addition, our calculations reveal that during the single-electron transfer (SET) process, the C-I bond cleavage in iodonium ylide and new C-C bond formation between resultant aryl radical and cationic quinoxaline species take place in a concerned manner. This enables the arylation reaction to efficiently proceed along an energy-efficient route.

12.
J Org Chem ; 89(11): 7591-7597, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38723145

RESUMEN

In this study, we present an efficient approach for the synthesis of 3-sulfenyl indoles through an electron donor-acceptor (EDA) complex-promoted photoreaction. This sulfenylation reaction leverages sulfonyl chlorides as the sulfur source and employs PPh3 as the reductant without the need for any transition-metal catalyst or photocatalyst. At the same time, the relaxation process of the excited EDA complex was theoretically investigated at the method and multiconfiguration second-order perturbation//complete active space self-consistent field/PCM level of theory, which involves the π bond of indoles injecting an electron to the antibonding orbital of the S-Cl bond in arylsulfonyl chlorides.

13.
J Org Chem ; 89(6): 4031-4036, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38447165

RESUMEN

Construction of medium-sized ring compounds remains challenging in synthetic chemistry. Herein, we describe the synthesis of medium-sized lactams via a photoinduced ring expansion of benzo-fused cyclic ketones using graphitic carbon nitride (g-C3N4) as a photocatalyst. The ring expansion protocol provided an efficient access to 8-10-membered lactams in good yields and displayed good tolerance to a range of functional groups. The mechanism studies revealed that the photochemical reaction proceeds via an intermediary of a nitrogen radical, which is generated through an oxidative hydrogen atom transfer (HAT) process.

14.
Environ Res ; 252(Pt 1): 118800, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38555088

RESUMEN

With global climate changing, hypo-salinity events are increasing in frequency and duration because of continuous rainfall and freshwater inflow, which causes reduced cytosolic osmolarity and cellular stress responses in aquatic animals. Sea cucumbers are considered stenohaline because they lack osmoregulatory organs and are vulnerable to salinity fluctuations. In this study, we performed multiple biochemical assays, de novo transcriptomics, and widely targeted metabolomics to comprehensively explore the osmoregulatory mechanisms and physiological responses of sea cucumber Holothuria moebii to hypo-osmotic stress, which is a representative specie that is frequently exposed to hypo-saline intertidal zones. Our results found that H. moebii contracted their ambulacral feet and oral tentacles, and the coelomic fluid ion concentrations were reduced to be consistent with the environment. The microvilli of intestines and respiratory trees underwent degeneration, and the cytoplasm exhibited swelling and vacuolation. Moreover, the Na+, K+, and Cl- concentrations and Na+/K+-ATPase activity were significantly reduced under hypo-osmotic stress. The decrease in protein kinase A activity and increase in 5'-AMP level indicated a significant inhibition of the cAMP signaling pathway to regulate ion concentrations. And small intracellular organic molecules (amino acids, nucleotides and their derivatives) also play crucial roles in osmoregulation through oxidative deamination of glutamate, nucleotide catabolism, and nucleic acid synthesis. Moreover, lysosomes and peroxisomes removed oxidative damage, whereas antioxidant metabolites, such as N-acetyl amino acids and glutathione, were increased to resist oxidative stress. With prolonged hypo-osmotic stress, glycerophospholipid metabolism was enhanced to maintain membrane stability. Furthermore, acyl-CoA-binding protein activity was significantly inhibited, and only a small amount of acylcarnitine was significantly accumulated, which indicated a disruption in energy metabolism. PPAR signaling pathway and choline content were up-regulated to promote fatty acid metabolism under hypo-osmotic stress. Overall, our results provide new insights into the osmoregulatory mechanisms and physiological responses of sea cucumbers to hypo-osmotic stress.


Asunto(s)
Antioxidantes , Metabolismo Energético , Holothuria , Osmorregulación , Presión Osmótica , Animales , Holothuria/fisiología , Antioxidantes/metabolismo , Salinidad
15.
Int J Gynecol Cancer ; 34(7): 1034-1040, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38724236

RESUMEN

OBJECTIVE: Cytotoxic chemotherapy for ovarian cancer can be augmented by co-administration of vascular endothelial growth factor inhibitors but these are contraindicated in patients with bowel obstruction due to the risk of gastrointestinal perforation. We evaluated the safety and feasibility of paclitaxel plus cediranib to treat patients with platinum-resistant ovarian cancer at risk of malignant bowel obstruction. METHODS: A phase II trial included eligible patients between March 2018 and February 2021, identified by clinical symptoms and radiographic risk factors for malignant bowel obstruction. Cediranib (20 mg/day) was added to paclitaxel (70 mg/m2/week) within 9 weeks of starting paclitaxel if pretreatment bowel symptoms had improved. The primary endpoint was the number of patients treated for ≥5 days with cediranib that were free of grade 3-5 gastrointestinal perforation or fistula. Secondary endpoints were hospitalization for bowel obstruction, grade ≥3 adverse events, treatment compliance assessed by relative dose intensity, objective response, progression-free survival, and overall survival. RESULTS: Thirty patients were recruited. Of these, 12 received paclitaxel alone and 17 received paclitaxel and cediranib in combination. One patient died before starting treatment. No patient developed a grade 3-5 gastrointestinal perforation or fistula (one sided 95% confidence interval (CI) upper limit 0.16). One patient required hospitalization for bowel obstruction but recovered with conservative management. The most common cediranib-related grade ≥3 adverse events were fatigue (3/17), diarrhorea (2/17), and hypomagnesemia (2/17). Relative dose intensity for paclitaxel was 90% (interquartile range (IQR) 85-100%; n=29) and for cediranib 88% (IQR 76-93%; n=17). The objective response in patients who received paclitaxel and cediranib was 65.0% (one complete and 10 partial responses). Median progression-free survival was 6.9 months (95% CI 4.4-11.5 months; n=17) and overall survival was 19.4 months (95% CI 10.1-20.4 months; n=17). Median follow-up was 12.4 months (8.9-not reached; n=17). CONCLUSIONS: The unexpectedly high withdrawal rate during paclitaxel alone, before introducing cediranib, meant we were unable to definitely conclude that paclitaxel plus cediranib did not cause gastrointestinal perforation or fistula. The regimen was however tolerated. TRIAL REGISTRATION NUMBER: EudraCT 2016-004618-93.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Obstrucción Intestinal , Neoplasias Ováricas , Paclitaxel , Quinazolinas , Humanos , Femenino , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Persona de Mediana Edad , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/complicaciones , Anciano , Obstrucción Intestinal/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quinazolinas/administración & dosificación , Quinazolinas/efectos adversos , Resistencia a Antineoplásicos , Adulto , Esquema de Medicación , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Indoles
16.
Nucleic Acids Res ; 50(D1): D60-D71, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34664666

RESUMEN

DNA methylation is known to be the most stable epigenetic modification and has been extensively studied in relation to cell differentiation, development, X chromosome inactivation and disease. Allele-specific DNA methylation (ASM) is a well-established mechanism for genomic imprinting and regulates imprinted gene expression. Previous studies have confirmed that certain special regions with ASM are susceptible and closely related to human carcinogenesis and plant development. In addition, recent studies have proven ASM to be an effective tumour marker. However, research on the functions of ASM in diseases and development is still extremely scarce. Here, we collected 4400 BS-Seq datasets and 1598 corresponding RNA-Seq datasets from 47 species, including human and mouse, to establish a comprehensive ASM database. We obtained the data on DNA methylation level, ASM and allele-specific expressed genes (ASEGs) and further analysed the ASM/ASEG distribution patterns of these species. In-depth ASM distribution analysis and differential methylation analysis conducted in nine cancer types showed results consistent with the reported changes in ASM in key tumour genes and revealed several potential ASM tumour-related genes. Finally, integrating these results, we constructed the first well-resourced and comprehensive ASM database for 47 species (ASMdb, www.dna-asmdb.com).


Asunto(s)
Metilación de ADN/genética , Bases de Datos Genéticas , Epigénesis Genética/genética , Impresión Genómica/genética , Alelos , Animales , Islas de CpG/genética , Humanos , Ratones , Polimorfismo de Nucleótido Simple/genética , RNA-Seq , Inactivación del Cromosoma X/genética
17.
Nucleic Acids Res ; 50(10): 5443-5466, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35061895

RESUMEN

Although recent regulatory approval of splice-switching oligonucleotides (SSOs) for the treatment of neuromuscular disease such as Duchenne muscular dystrophy has been an advance for the splice-switching field, current SSO chemistries have shown limited clinical benefit due to poor pharmacology. To overcome limitations of existing technologies, we engineered chimeric stereopure oligonucleotides with phosphorothioate (PS) and phosphoryl guanidine-containing (PN) backbones. We demonstrate that these chimeric stereopure oligonucleotides have markedly improved pharmacology and efficacy compared with PS-modified oligonucleotides, preventing premature death and improving median survival from 49 days to at least 280 days in a dystrophic mouse model with an aggressive phenotype. These data demonstrate that chemical optimization alone can profoundly impact oligonucleotide pharmacology and highlight the potential for continued innovation around the oligonucleotide backbone. More specifically, we conclude that chimeric stereopure oligonucleotides are a promising splice-switching modality with potential for the treatment of neuromuscular and other genetic diseases impacting difficult to reach tissues such as the skeletal muscle and heart.


Asunto(s)
Distrofia Muscular de Duchenne , Oligonucleótidos Antisentido/química , Oligonucleótidos Fosforotioatos/química , Animales , Exones , Ratones , Músculo Esquelético , Distrofia Muscular de Duchenne/tratamiento farmacológico , Distrofia Muscular de Duchenne/terapia , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Fosforotioatos/farmacología , Empalme del ARN/efectos de los fármacos
18.
BMC Pediatr ; 24(1): 330, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741052

RESUMEN

BACKGROUND: Thalassemias represent some of the most common monogenic diseases worldwide and are caused by variations in human hemoglobin genes which disrupt the balance of synthesis between the alpha and beta globin chains. Thalassemia gene detection technology is the gold standard to achieve accurate detection of thalassemia, but in clinical practice, most of the tests are only for common genotypes, which can easily lead to missing or misdiagnosis of rare thalassemia genotypes. CASE PRESENTATION: We present the case of an 18-year-old Chinese female with abnormal values of routine hematological indices who was admitted for genetic screening for thalassemia. Genomic DNA was extracted and used for the genetic assays. Gap polymerase chain reaction and agarose gel electrophoresis were performed to detect HBA gene deletions, while PCR-reverse dot blot hybridization was used to detect point mutations in the HBA and HBB genes. Next-generation sequencing and third-generation sequencing (TGS) were used to identify known and potentially novel genotypes of thalassemia. We identified a novel complex variant αHb WestmeadαHb Westmeadαanti3.7/-α3.7 in a patient with rare alpha-thalassemia. CONCLUSIONS: Our study identified a novel complex variant that expands the thalassemia gene variants spectrum. Meanwhile, the study suggests that TGS could effectively improve the specificity of thalassemia gene detection, and has promising potential for the discovery of novel thalassemia genotypes, which could also improve the accuracy of genetic counseling. Couples who are thalassemia carriers have the opportunity to reduce their risk of having a child with thalassemia.


Asunto(s)
Talasemia alfa , Humanos , Talasemia alfa/genética , Talasemia alfa/diagnóstico , Femenino , Adolescente , Secuenciación de Nucleótidos de Alto Rendimiento , Genotipo , Pruebas Genéticas/métodos , Mutación Puntual , Hemoglobinas Anormales/genética
19.
Chem Biodivers ; : e202401767, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39185921

RESUMEN

Insect transient receptor potential vanilloid (TRPV) channels are critical targets for insecticides. In this study, various scaffold-hopping strategies were employed in the rational design of pyridylhydrazono derivatives as potential insect TRPV channels modulators. Insecticidal bioassay demonstrated that the initial target compounds exhibited lower insecticidal activity compared to pymetrozine, with the optimal compound B3 exhibiting a mortality rate of 53.3% against Aphis craccivora at 400 mg·L-1. Conformation analysis indicated that the high energy barrier required for the transition from the lowest-energy conformation to the active conformation may be a key factor contributing to the reduced insecticidal activities of the target compounds. Further structural optimizations aimed at reducing this energy barrier through binding mode-based conformation regulation led to the identification of optimal target 4-(3'-pyridylhydrazono)pyrazol-5-one derivatives C1 and C2. These compounds exhibited reduced transition energy barriers and improved insecticidal activity, with moderate mortality rate of 66.3% and 75.7% against A. craccivora at 400 mg·L-1, respectively. These findings provide valuable insights for future research on the discovery of insect TRPV modulators and have significant implications for the development of more effective agricultural insecticides.

20.
Pharmacogenet Genomics ; 33(2): 24-34, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36729770

RESUMEN

OBJECTIVE: To evaluate Chinese long-term economic impact of universal human leukocyte antigen B (HLA-B)*58:01 genotyping-guided urate-lowering therapy or febuxostat initiation therapy for gout patients with mild to moderate chronic kidney disease (CKD) from perspective of healthcare system. METHODS: A Markov model embedded in a decision tree was structured including four mutually exclusive health states (uncontrolled-on-therapy, controlled-on-therapy, uncontrolled-off-therapy, and death). Mainly based on Chinese real-world data, the incremental costs per quality-adjusted life years (QALYs) gained were evaluated from three groups (universal HLA-B*58:01 testing strategy, and no genotyping prior to allopurinol or febuxostat initiation therapy) at 25-year time horizon. All costs were adjusted to 2021 levels based on Chinese Consumer Price Index and were discounted by 5% annually. One-way and probability sensitivity analysis were performed. RESULTS: Among these three groups, universal HLA-B*58:01 genotyping was the most cost-effective strategy in base-case analysis according to Chinese average willingness-to-pay threshold of $37 654.50 per QALY. The based incremental cost-effectiveness ratio was $31784.55 per QALY, associated with 0.046 additional QALYs and $1463.81 increment costs per patient at a 25-year time horizon compared with no genotyping prior to allopurinol initiation strategy. Sensitivity analysis showed 64.3% robustness of these results. CONCLUSION: From Chinese perspective of healthcare system, HLA-B*58:01 genotyping strategy was cost-effective for gout patients with mild to moderate CKD in mainland China, especially in the most developed area, such as Beijing and Shanghai. Therefore, we suggest China's health authorities choose the genotyping strategy and make different recommendations according to the differences of local conditions.


Asunto(s)
Gota , Antígenos HLA-B , Insuficiencia Renal Crónica , Humanos , Alopurinol/uso terapéutico , China , Análisis Costo-Beneficio , Pueblos del Este de Asia , Febuxostat/uso terapéutico , Gota/tratamiento farmacológico , Gota/genética , Supresores de la Gota/uso terapéutico , Antígenos HLA-B/genética , Años de Vida Ajustados por Calidad de Vida , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/genética
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