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1.
Mol Cell ; 84(15): 2900-2917.e10, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39032490

RESUMEN

INTS11 and CPSF73 are metal-dependent endonucleases for Integrator and pre-mRNA 3'-end processing, respectively. Here, we show that the INTS11 binding partner BRAT1/CG7044, a factor important for neuronal fitness, stabilizes INTS11 in the cytoplasm and is required for Integrator function in the nucleus. Loss of BRAT1 in neural organoids leads to transcriptomic disruption and precocious expression of neurogenesis-driving transcription factors. The structures of the human INTS9-INTS11-BRAT1 and Drosophila dIntS11-CG7044 complexes reveal that the conserved C terminus of BRAT1/CG7044 is captured in the active site of INTS11, with a cysteine residue directly coordinating the metal ions. Inspired by these observations, we find that UBE3D is a binding partner for CPSF73, and UBE3D likely also uses a conserved cysteine residue to directly coordinate the active site metal ions. Our studies have revealed binding partners for INTS11 and CPSF73 that behave like cytoplasmic chaperones with a conserved impact on the nuclear functions of these enzymes.


Asunto(s)
Núcleo Celular , Citoplasma , Proteínas de Drosophila , Unión Proteica , Humanos , Animales , Núcleo Celular/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética , Citoplasma/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Endonucleasas/metabolismo , Endonucleasas/genética , Células HEK293 , Neurogénesis/genética , Factor de Especificidad de Desdoblamiento y Poliadenilación/metabolismo , Factor de Especificidad de Desdoblamiento y Poliadenilación/genética , Dominio Catalítico
2.
Nature ; 621(7978): 336-343, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37674081

RESUMEN

Birds are descended from non-avialan theropod dinosaurs of the Late Jurassic period, but the earliest phase of this evolutionary process remains unclear owing to the exceedingly sparse and spatio-temporally restricted fossil record1-5. Information about the early-diverging species along the avialan line is crucial to understand the evolution of the characteristic bird bauplan, and to reconcile phylogenetic controversies over the origin of birds3,4. Here we describe one of the stratigraphically youngest and geographically southernmost Jurassic avialans, Fujianvenator prodigiosus gen. et sp. nov., from the Tithonian age of China. This specimen exhibits an unusual set of morphological features that are shared with other stem avialans, troodontids and dromaeosaurids, showing the effects of evolutionary mosaicism in deep avialan phylogeny. F. prodigiosus is distinct from all other Mesozoic avialan and non-avialan theropods in having a particularly elongated hindlimb, suggestive of a terrestrial or wading lifestyle-in contrast with other early avialans, which exhibit morphological adaptations to arboreal or aerial environments. During our fieldwork in Zhenghe where F. prodigiosus was found, we discovered a diverse assemblage of vertebrates dominated by aquatic and semi-aquatic species, including teleosts, testudines and choristoderes. Using in situ radioisotopic dating and stratigraphic surveys, we were able to date the fossil-containing horizons in this locality-which we name the Zhenghe Fauna-to 148-150 million years ago. The diversity of the Zhenghe Fauna and its precise chronological framework will provide key insights into terrestrial ecosystems of the Late Jurassic.


Asunto(s)
Aves , Dinosaurios , Fósiles , Animales , China , Dinosaurios/anatomía & histología , Dinosaurios/clasificación , Ecosistema , Mosaicismo , Filogenia , Aves/anatomía & histología , Aves/clasificación , Historia Antigua , Miembro Posterior
3.
Cell ; 146(6): 969-79, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-21906795

RESUMEN

Acetylation of histone and nonhistone proteins is an important posttranslational modification affecting many cellular processes. Here, we report that NuA4 acetylation of Sip2, a regulatory ß subunit of the Snf1 complex (yeast AMP-activated protein kinase), decreases as cells age. Sip2 acetylation, controlled by antagonizing NuA4 acetyltransferase and Rpd3 deacetylase, enhances interaction with Snf1, the catalytic subunit of Snf1 complex. Sip2-Snf1 interaction inhibits Snf1 activity, thus decreasing phosphorylation of a downstream target, Sch9 (homolog of Akt/S6K), and ultimately leading to slower growth but extended replicative life span. Sip2 acetylation mimetics are more resistant to oxidative stress. We further demonstrate that the anti-aging effect of Sip2 acetylation is independent of extrinsic nutrient availability and TORC1 activity. We propose a protein acetylation-phosphorylation cascade that regulates Sch9 activity, controls intrinsic aging, and extends replicative life span in yeast.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/fisiología , Transactivadores/metabolismo , Acetilación , Restricción Calórica , División Celular , Histona Acetiltransferasas/metabolismo , Histona Desacetilasas/metabolismo , Proteínas Quinasas/metabolismo , Saccharomyces cerevisiae/enzimología , Factores de Transcripción/metabolismo
5.
Nucleic Acids Res ; 52(16): 9966-9977, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39077943

RESUMEN

Genome segregation is a fundamental process that preserves the genetic integrity of all organisms, but the mechanisms driving genome segregation in archaea remain enigmatic. This study delved into the unknown function of SegC (SSO0033), a novel protein thought to be involved in chromosome segregation in archaea. Using fluorescence polarization DNA binding assays, we discovered the ability of SegC to bind DNA without any sequence preference. Furthermore, we determined the crystal structure of SegC at 2.8 Å resolution, revealing the multimeric configuration and forming a large positively charged surface that can bind DNA. SegC has a tertiary structure folding similar to those of the ThDP-binding fold superfamily, but SegC shares only 5-15% sequence identity with those proteins. Unexpectedly, we found that SegC has nucleotide triphosphatase (NTPase) activity. We also determined the SegC-ADP complex structure, identifying the NTP binding pocket and relative SegC residues involved in the interaction. Interestingly, images from negative-stain electron microscopy revealed that SegC forms filamentous structures in the presence of DNA and NTPs. Further, more uniform and larger SegC-filaments are observed, when SegA-ATP was added. Notably, the introduction of SegB disrupts these oligomers, with ATP being essential for regulating filament formation. These findings provide insights into the functional and structural role of SegC in archaeal chromosome segregation.


Asunto(s)
Proteínas Arqueales , Segregación Cromosómica , Modelos Moleculares , Proteínas Arqueales/química , Proteínas Arqueales/metabolismo , Proteínas Arqueales/genética , Unión Proteica , Cristalografía por Rayos X , Adenosina Difosfato/metabolismo , Adenosina Difosfato/química , Sitios de Unión , ADN de Archaea/metabolismo , ADN de Archaea/química , ADN de Archaea/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/ultraestructura
6.
Nucleic Acids Res ; 52(12): 7321-7336, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38842933

RESUMEN

The ParABS system, composed of ParA (an ATPase), ParB (a DNA binding protein), and parS (a centromere-like DNA), regulates bacterial chromosome partition. The ParB-parS partition complex interacts with the nucleoid-bound ParA to form the nucleoid-adaptor complex (NAC). In Helicobacter pylori, ParA and ParB homologs are encoded as HpSoj and HpSpo0J (HpParA and HpParB), respectively. We determined the crystal structures of the ATP hydrolysis deficient mutant, HpParAD41A, and the HpParAD41A-DNA complex. We assayed the CTPase activity of HpParB and identified two potential DNA binding modes of HpParB regulated by CTP, one is the specific DNA binding by the DNA binding domain and the other is the non-specific DNA binding through the C-terminal domain under the regulation of CTP. We observed an interaction between HpParAD41A and the N-terminus fragment of HpParB (residue 1-10, HpParBN10) and determined the crystal structure of the ternary complex, HpParAD41A-DNA-HpParBN10 complex which mimics the NAC formation. HpParBN10 binds near the HpParAD41A dimer interface and is clamped by flexible loops, L23 and L34, through a specific cation-π interaction between Arg9 of HpParBN10 and Phe52 of HpParAD41A. We propose a molecular mechanism model of the ParABS system providing insight into chromosome partition in bacteria.


Asunto(s)
Proteínas Bacterianas , Cromosomas Bacterianos , Proteínas de Unión al ADN , Helicobacter pylori , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Helicobacter pylori/genética , Helicobacter pylori/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Cromosomas Bacterianos/metabolismo , Cromosomas Bacterianos/química , Cromosomas Bacterianos/genética , Modelos Moleculares , Cristalografía por Rayos X , Unión Proteica , ADN Bacteriano/metabolismo , ADN Bacteriano/química , ADN Bacteriano/genética , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Segregación Cromosómica , Adenosina Trifosfato/metabolismo , Sitios de Unión
7.
J Neurosci ; 44(17)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38453467

RESUMEN

Pain perception arises from the integration of prior expectations with sensory information. Although recent work has demonstrated that treatment expectancy effects (e.g., placebo hypoalgesia) can be explained by a Bayesian integration framework incorporating the precision level of expectations and sensory inputs, the key factor modulating this integration in stimulus expectancy-induced pain modulation remains unclear. In a stimulus expectancy paradigm combining emotion regulation in healthy male and female adults, we found that participants' voluntary reduction in anticipatory anxiety and pleasantness monotonically reduced the magnitude of pain modulation by negative and positive expectations, respectively, indicating a role of emotion. For both types of expectations, Bayesian model comparisons confirmed that an integration model using the respective emotion of expectations and sensory inputs explained stimulus expectancy effects on pain better than using their respective precision. For negative expectations, the role of anxiety is further supported by our fMRI findings that (1) functional coupling within anxiety-processing brain regions (amygdala and anterior cingulate) reflected the integration of expectations with sensory inputs and (2) anxiety appeared to impair the updating of expectations via suppressed prediction error signals in the anterior cingulate, thus perpetuating negative expectancy effects. Regarding positive expectations, their integration with sensory inputs relied on the functional coupling within brain structures processing positive emotion and inhibiting threat responding (medial orbitofrontal cortex and hippocampus). In summary, different from treatment expectancy, pain modulation by stimulus expectancy emanates from emotion-modulated integration of beliefs with sensory evidence and inadequate belief updating.


Asunto(s)
Anticipación Psicológica , Ansiedad , Imagen por Resonancia Magnética , Humanos , Masculino , Femenino , Ansiedad/psicología , Ansiedad/fisiopatología , Adulto , Anticipación Psicológica/fisiología , Adulto Joven , Percepción del Dolor/fisiología , Dolor/psicología , Dolor/fisiopatología , Teorema de Bayes , Emociones/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Encéfalo/fisiología , Placer/fisiología , Mapeo Encefálico
8.
RNA ; 29(11): 1673-1690, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37562960

RESUMEN

U7 snRNP is a multisubunit endonuclease required for 3' end processing of metazoan replication-dependent histone pre-mRNAs. In contrast to the spliceosomal snRNPs, U7 snRNP lacks the Sm subunits D1 and D2 and instead contains two related proteins, Lsm10 and Lsm11. The remaining five subunits of the U7 heptameric Sm ring, SmE, F, G, B, and D3, are shared with the spliceosomal snRNPs. The pathway that assembles the unique ring of U7 snRNP is unknown. Here, we show that a heterodimer of Lsm10 and Lsm11 tightly interacts with the methylosome, a complex of the arginine methyltransferase PRMT5, MEP50, and pICln known to methylate arginines in the carboxy-terminal regions of the Sm proteins B, D1, and D3 during the spliceosomal Sm ring assembly. Both biochemical and cryo-EM structural studies demonstrate that the interaction is mediated by PRMT5, which binds and methylates two arginine residues in the amino-terminal region of Lsm11. Surprisingly, PRMT5 also methylates an amino-terminal arginine in SmE, a subunit that does not undergo this type of modification during the biogenesis of the spliceosomal snRNPs. An intriguing possibility is that the unique methylation pattern of Lsm11 and SmE plays a vital role in the assembly of the U7 snRNP.


Asunto(s)
Ribonucleoproteína Nuclear Pequeña U7 , Ribonucleoproteínas Nucleares Pequeñas , Animales , Ribonucleoproteína Nuclear Pequeña U7/química , Metilación , Ribonucleoproteínas Nucleares Pequeñas/metabolismo , Histonas/metabolismo , Arginina/química
9.
Nature ; 574(7780): 722-725, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31645759

RESUMEN

The enzyme protochlorophyllide oxidoreductase (POR) catalyses a light-dependent step in chlorophyll biosynthesis that is essential to photosynthesis and, ultimately, all life on Earth1-3. POR, which is one of three known light-dependent enzymes4,5, catalyses reduction of the photosensitizer and substrate protochlorophyllide to form the pigment chlorophyllide. Despite its biological importance, the structural basis for POR photocatalysis has remained unknown. Here we report crystal structures of cyanobacterial PORs from Thermosynechococcus elongatus and Synechocystis sp. in their free forms, and in complex with the nicotinamide coenzyme. Our structural models and simulations of the ternary protochlorophyllide-NADPH-POR complex identify multiple interactions in the POR active site that are important for protochlorophyllide binding, photosensitization and photochemical conversion to chlorophyllide. We demonstrate the importance of active-site architecture and protochlorophyllide structure in driving POR photochemistry in experiments using POR variants and protochlorophyllide analogues. These studies reveal how the POR active site facilitates light-driven reduction of protochlorophyllide by localized hydride transfer from NADPH and long-range proton transfer along structurally defined proton-transfer pathways.


Asunto(s)
Clorofila/biosíntesis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/química , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Synechococcus/enzimología , Synechocystis/enzimología , Catálisis , Clorofila/química , Estructura Molecular , Fotoquímica , Protoclorofilida/metabolismo , Relación Estructura-Actividad , Especificidad por Sustrato
10.
PLoS Genet ; 18(1): e1009952, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35051171

RESUMEN

Overweight and obese are risk factors for various diseases. In Taiwan, the combined prevalence of overweight and obesity has increased dramatically. Here, we conducted a genome-wide association study (GWAS) on four adiposity traits, including body-mass index (BMI), body fat percentage (BF%), waist circumference (WC), and waist-hip ratio (WHR), using the data for more than 21,000 subjects in Taiwan Biobank. Associations were evaluated between 6,546,460 single-nucleotide polymorphisms (SNPs) and adiposity traits, yielding 13 genome-wide significant (GWS) adiposity-associated trait-loci pairs. A known gene, FTO, as well as two BF%-associated loci (GNPDA2-GABRG1 [4p12] and RNU6-2-PIAS1 [15q23]) were identified as pleiotropic effects. Moreover, RALGAPA1 was found as a specific genetic predisposing factor to high BMI in a Taiwanese population. Compared to other populations, a slightly lower heritability of the four adiposity traits was found in our cohort. Surprisingly, we uncovered the importance of neural pathways that might influence BF%, WC and WHR in the Taiwanese (East Asian) population. Additionally, a moderate genetic correlation between the WHR and BMI (γg = 0.52; p = 2.37×10-9) was detected, suggesting different genetic determinants exist for abdominal adiposity and overall adiposity. In conclusion, the obesity-related genetic loci identified here provide new insights into the genetic underpinnings of adiposity in the Taiwanese population.


Asunto(s)
Adiposidad/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Adulto , Bancos de Muestras Biológicas , Estudios de Cohortes , Femenino , Proteínas Activadoras de GTPasa/genética , Humanos , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/genética , Obesidad/genética , Sobrepeso/genética , Polimorfismo de Nucleótido Simple , Taiwán
11.
Proc Natl Acad Sci U S A ; 119(32): e2123379119, 2022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35914151

RESUMEN

Xylomyrocins, a unique group of nonribosomal peptide secondary metabolites, were discovered in Paramyrothecium and Colletotrichum spp. fungi by employing a combination of high-resolution tandem mass spectrometry (HRMS/MS)-based chemometrics, comparative genome mining, gene disruption, stable isotope feeding, and chemical complementation techniques. These polyol cyclodepsipeptides all feature an unprecedented d-xylonic acid moiety as part of their macrocyclic scaffold. This biosynthon is derived from d-xylose supplied by xylooligosaccharide catabolic enzymes encoded in the xylomyrocin biosynthetic gene cluster, revealing a novel link between carbohydrate catabolism and nonribosomal peptide biosynthesis. Xylomyrocins from different fungal isolates differ in the number and nature of their amino acid building blocks that are nevertheless incorporated by orthologous nonribosomal peptide synthetase (NRPS) enzymes. Another source of structural diversity is the variable choice of the nucleophile for intramolecular macrocyclic ester formation during xylomyrocin chain termination. This nucleophile is selected from the multiple available alcohol functionalities of the polyol moiety, revealing a surprising polyspecificity for the NRPS terminal condensation domain. Some xylomyrocin congeners also feature N-methylated amino acid residues in positions where the corresponding NRPS modules lack N-methyltransferase (M) domains, providing a rare example of promiscuous methylation in the context of an NRPS with an otherwise canonical, collinear biosynthetic program.


Asunto(s)
Depsipéptidos , Proteínas Fúngicas , Hongos , Aminoácidos/química , Metabolismo de los Hidratos de Carbono , Quimiometría , Depsipéptidos/química , Depsipéptidos/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Hongos/genética , Hongos/metabolismo , Familia de Multigenes , Biosíntesis de Péptidos Independientes de Ácidos Nucleicos , Péptido Sintasas/química , Azúcares
12.
Nano Lett ; 24(34): 10664-10673, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39140448

RESUMEN

Here we report a brand-new bioactive polymer featuring sulfonium moieties that exhibits the capability of inducing immunogenic cell death (ICD) for anticancer therapy. The optimized polysulfonium presents a wide spectrum of potent anticancer activity and remarkable selectivity. In-depth mechanistic studies reveal that the polymer exerts its cytotoxic effects on cancer cells through a membrane-disrupting mechanism. This further initiates the release of a plethora of damage-associated molecular patterns, effectively triggering ICD and resulting in systemic anticancer immune responses. Notably, the compound demonstrated significant efficacy in suppressing tumor growth in the B16-F10 melanoma tumor model. Furthermore, it exhibits robust immune memory effects, effectively suppressing tumor recurrence and metastasis in both the rechallenge model and the lung metastatic tumor model. To the best of our knowledge, the study represents the pioneering exportation of cationic polysulfoniums, showcasing not only their remarkable safety and efficacy against primary tumors but also their unique ability in activating long-term immune memory.


Asunto(s)
Antineoplásicos , Muerte Celular Inmunogénica , Polímeros , Animales , Muerte Celular Inmunogénica/efectos de los fármacos , Ratones , Humanos , Línea Celular Tumoral , Polímeros/química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Compuestos de Sulfonio/química , Compuestos de Sulfonio/farmacología , Compuestos de Sulfonio/uso terapéutico , Melanoma Experimental/inmunología , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología
13.
Am J Physiol Cell Physiol ; 326(1): C206-C213, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38047298

RESUMEN

People with primary focal hyperhidrosis (PFH) usually have an overactive sympathetic nervous system, which can activate the sweat glands through the chemical messenger of acetylcholine. The role of aquaporin 5 (AQP5) and Na-K-2Cl cotransporter 1 (NKCC1) in PFH is still unknown. The relative mRNA and protein levels of AQP5 and NKCC1 in the sweat gland tissues of three subtypes of patients with PFH (primary palmar hyperhidrosis, PPH; primary axillary hyperhidrosis, PAH; and primary craniofacial hyperhidrosis, PCH) were detected with real-time PCR (qPCR) and Western blot. Primary sweat gland cells from healthy controls (NPFH-SG) were incubated with different concentrations of acetylcholine, and the relative mRNA and protein expression of AQP5 and NKCC1 were also detected. NPFH-SG cells were also transfected with si-AQP5 or shNKCC1, and acetylcholine stimulation-induced calcium transients were assayed with Fluo-3 AM calcium assay. Upregulated AQP5 and NKCC1 expression were observed in sweat gland tissues, and AQP5 demonstrated a positive Pearson correlation with NKCC1 in patients with PPH (r = 0.66, P < 0.001), patients with PAH (r = 0.71, P < 0.001), and patients with PCH (r = 0.62, P < 0.001). Upregulated AQP5 and NKCC1 expression were also detected in primary sweat gland cells derived from three subtypes of patients with PFH when compared with primary sweat gland cells derived from healthy control. Acetylcholine stimulation could induce the upregulated AQP5 and NKCC1 expression in NPFH-SG cells, and AQP5 or NKCC1 inhibitions attenuated the calcium transients induced by acetylcholine stimulation in NPFH-SG cells. The dependence of ACh-stimulated calcium transients on AQP5 and NKCC1 expression may be involved in the development of PFH.NEW & NOTEWORTHY The dependence of ACh-stimulated calcium transients on AQP5 and Na-K-2Cl cotransporter 1 (NKCC1) expression may be involved in the development of primary focal hyperhidrosis (PFH).


Asunto(s)
Acuaporina 5 , Hiperhidrosis , Humanos , Acetilcolina/farmacología , Acetilcolina/metabolismo , Acuaporina 5/genética , Acuaporina 5/metabolismo , Calcio/metabolismo , Técnicas de Cultivo de Célula , Hiperhidrosis/metabolismo , ARN Mensajero/metabolismo , Glándulas Sudoríparas/química , Glándulas Sudoríparas/metabolismo
14.
J Biol Chem ; 299(4): 103047, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36822327

RESUMEN

Human cleavage and polyadenylation specificity factor (CPSF)73 (also known as CPSF3) is the endoribonuclease that catalyzes the cleavage reaction for the 3'-end processing of pre-mRNAs. The active site of CPSF73 is located at the interface between a metallo-ß-lactamase domain and a ß-CASP domain. Two metal ions are coordinated by conserved residues, five His and two Asp, in the active site, and they are critical for the nuclease reaction. The metal ions have long been thought to be zinc ions, but their exact identity has not been examined. Here we present evidence from inductively coupled plasma mass spectrometry and X-ray diffraction analyses that a mixture of metal ions, including Fe, Zn, and Mn, is present in the active site of CPSF73. The abundance of the various metal ions is different in samples prepared from different expression hosts. Zinc is present at less than 20% abundance in a sample expressed in insect cells, but the sample is active in cleaving a pre-mRNA substrate in a reconstituted canonical 3'-end processing machinery. Zinc is present at 75% abundance in a sample expressed in human cells, which has comparable endonuclease activity. We also observe a mixture of metal ions in the active site of the CPSF73 homolog INTS11, the endonuclease for Integrator. Taken together, our results provide further insights into the role of metal ions in the activity of CPSF73 and INTS11 for RNA 3'-end processing.


Asunto(s)
Factor de Especificidad de Desdoblamiento y Poliadenilación , Endonucleasas , Humanos , Dominio Catalítico , Factor de Especificidad de Desdoblamiento y Poliadenilación/química , Factor de Especificidad de Desdoblamiento y Poliadenilación/metabolismo , Endonucleasas/química , Endonucleasas/metabolismo , Procesamiento Postranscripcional del ARN , Zinc/metabolismo
15.
J Am Chem Soc ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858162

RESUMEN

Understanding how life's essential homochiral biopolymers arose from racemic precursors is a challenging quest. Herein, we present a groundbreaking approach involving hierarchical chiral assembly-driven stereoselective ring-opening polymerization of ε-benzyloxycarbonyl-l/d-lysine N-carboxyanhydrides assisted by ultrasonication in an aqueous medium. This method enabled a narrow dispersity within a few minutes and the achievement of high molecular weight for polypeptides, employing a living polymerization mechanism. The polymerization of l and d enantiomers yielded predominantly right- and left-handed superhelical assemblies in a one-pot preparation, respectively. Notably, stereoselective polypeptide segments were efficiently prepared through hierarchical assembly-driven polymerization of racemic monomers in the absence of a catalyst. This research offers an innovative strategy for the convenient preparations of stereoenriched polypeptides and, more importantly, sheds light on the plausible emergence of homochiral peptides in the origin of life.

16.
Lancet ; 402(10416): 2004-2017, 2023 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-37931629

RESUMEN

BACKGROUND: In patients with chronic kidney disease, SGLT2 inhibitors and endothelin A receptor antagonists (ERAs) can reduce albuminuria and glomerular filtration rate (GFR) decline. We assessed the albuminuria-lowering efficacy and safety of the ERA zibotentan combined with the SGLT2 inhibitor dapagliflozin. METHODS: ZENITH-CKD was a multicentre, randomised, double-blind, active-controlled clinical trial, done in 170 clinical practice sites in 18 countries. Adults (≥18 to ≤90 years) with an estimated GFR (eGFR) of 20 mL/min per 1·73 m2 or greater and a urinary albumin-to-creatinine ratio (UACR) of 150-5000 mg/g were randomly assigned (2:1:2) to 12 weeks of daily treatment with zibotentan 1·5 mg plus dapagliflozin 10 mg, zibotentan 0·25 mg plus dapagliflozin 10 mg, or dapagliflozin 10 mg plus placebo, as adjunct to angiotensin-converting enzyme inhibitors or angiotensin receptor blockers if tolerated. The primary endpoint was a change from baseline in log-transformed UACR (zibotentan 1·5 mg plus dapagliflozin vs dapagliflozin plus placebo) at week 12. Fluid retention was an event of special interest, defined as an increase in bodyweight of at least 3% (at least 2·5% must have been from total body water) from baseline or an increase of at least 100% in B-type natriuretic peptide (BNP) and either a BNP concentration greater than 200 pg/mL if without atrial fibrillation or BNP greater than 400 pg/mL if with atrial fibrillation. This trial is registered with ClinicalTrials.gov, NCT04724837, and is completed. FINDINGS: Between April 28, 2021, and Jan 17, 2023, we assessed 1492 participants for eligibility. For the main analysis, we randomly assigned 449 (30%) participants, 447 (99%) of whom (mean age 62·8 years [SD 12·1], 138 [31%] female, 309 [69%] male, 305 [68%] White, mean eGFR 46·7 mL/min per 1·73 m2 [SD 22·4], and median UACR 565·5 mg/g [IQR 243·0-1212·6]) received treatment with zibotentan 1·5 mg plus dapagliflozin (n=179 [40%]), zibotentan 0·25 mg plus dapagliflozin (n=91 [20%]), or dapagliflozin plus placebo (n=177 [40%]). Zibotentan 1·5 mg plus dapagliflozin and zibotentan 0·25 mg plus dapagliflozin reduced UACR versus dapagliflozin plus placebo throughout the treatment period of the study. At week 12, the difference in UACR versus dapagliflozin plus placebo was -33·7% (90% CI -42·5 to -23·5; p<0·0001) for zibotentan 1·5 mg plus dapagliflozin and -27·0% (90% CI -38·4 to -13·6; p=0·0022) for zibotentan 0·25 mg plus dapagliflozin. Fluid-retention events were observed in 33 (18%) of 179 participants in the zibotentan 1·5 mg plus dapagliflozin group, eight (9%) of 91 in the zibotentan 0·25 mg plus dapagliflozin group, and 14 (8%) of 177 in the dapagliflozin plus placebo group. INTERPRETATION: Zibotentan combined with dapagliflozin reduced albuminuria with an acceptable tolerability and safety profile and is an option to reduce chronic kidney disease progression in patients already receiving currently recommended therapy. FUNDING: AstraZeneca.


Asunto(s)
Fibrilación Atrial , Diabetes Mellitus Tipo 2 , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Albuminuria , Fibrilación Atrial/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Tasa de Filtración Glomerular , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Anciano , Anciano de 80 o más Años
17.
Radiology ; 312(3): e232815, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39254448

RESUMEN

Background Contrast-enhanced US (CEUS) can be used preoperatively for evaluating muscle invasion in bladder cancer, which is important for determining appropriate treatment. However, diagnostic criteria for assessing this at CEUS have not been standardized. Purpose To develop and validate a CEUS Vesical Imaging Reporting and Data System (VI-RADS) for evaluating muscle invasion in bladder cancer. Materials and Methods This single-center prospective study consecutively enrolled patients with suspected bladder cancer. Participants underwent transabdominal or intracavity CEUS between July 2021 and May 2023. Participants were divided into a training set and a validation set at a 2:1 ratio based on the chronologic order of enrollment. The training set was used to identify major imaging features to include in CEUS VI-RADS, and the likelihood of muscle invasion per category was determined using a pathologic reference standard. The optimal VI-RADS category cutoff for muscle invasion was determined with use of the maximum Youden index. The validation set was assessed by novice and expert readers and used to validate the diagnostic performance and interreader agreement of the developed system. Results Overall, 126 participants (median age, 64 years [IQR, 57-71 years]; 107 male) and 67 participants (median age, 64 years [IQR, 56-69 years]; 49 male) were included in the training and validation set, respectively. In the training set, the optimal CEUS VI-RADS category cutoff for muscle invasion was VI-RADS 4 or higher (Youden index, 0.77). In the validation set, CEUS VI-RADS achieved good performance for both novice and expert readers (area under the receiver operating characteristic curve, 0.80 [95% CI: 0.70, 0.90] vs 0.88 [95% CI: 0.80, 0.97]; P = .09). The interreader agreement regarding the evaluation of CEUS VI-RADS category was 0.77 (95% CI: 0.65, 0.85) for novice readers, 0.87 (95% CI: 0.79, 0.92) for expert readers, and 0.78 (95% CI: 0.70, 0.84) for all readers. Conclusion The developed CEUS VI-RADS showed good performance and interreader agreement for the assessment of muscle invasion in bladder cancer. Chinese Clinical Trial Registry no. ChiCTR2100049435 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Morrell in this issue.


Asunto(s)
Medios de Contraste , Invasividad Neoplásica , Ultrasonografía , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico por imagen , Neoplasias de la Vejiga Urinaria/patología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Ultrasonografía/métodos , Invasividad Neoplásica/diagnóstico por imagen , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria/patología , Reproducibilidad de los Resultados
18.
Artículo en Inglés | MEDLINE | ID: mdl-39198300

RESUMEN

The relationship among baseline pupil size, fixation stability, and inhibitory control were examined in this study. Participants performed a baseline eye measure in which they were instructed to stare at a fixation dot on screen for 2 min. Following the baseline eye measure, participants completed an antisaccade task to measure inhibitory control ability. We found a correlation between baseline pupil size variability and inhibitory control, as well as between fixation stability and inhibitory control. We showed that participants with better inhibitory control exhibited larger variability in pupil size, and those with better fixation stability showed superior inhibitory control ability. Overall, our results indicate that there are significant correlations between inhibitory control and baseline pupil size, as well as between inhibitory control and fixation stability.

19.
Small ; : e2402427, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751309

RESUMEN

Halogenated methane serves as a universal platform molecule for building high-value chemicals. Utilizing sodium chloride solution for photocatalytic methane chlorination presents an environmentally friendly method for methane conversion. However, competing reactions in gas-solid-liquid systems leads to low efficiency and selectivity in photocatalytic methane chlorination. Here, an in situ method is employed to fabricate a hydrophobic layer of TaOx species on the surface of NaTaO3. Through in-situ XPS and XANES spectra analysis, it is determined that TaOx is a coordination unsaturated species. The TaOx species transforms the surface properties from the inherent hydrophilicity of NaTaO3 to the hydrophobicity of TaOx/NaTaO3, which enhances the accessibility of CH4 for adsorption and activation, and thus promotes the methane chlorination reaction within the gas-liquid-solid three-phase system. The optimized TaOx/NaTaO3 photocatalyst has a good durability for multiple cycles of methane chlorination reactions, yielding CH3Cl at a rate of 233 µmol g-1 h-1 with a selectivity of 83%. In contrast, pure NaTaO3 exhibits almost no activity toward CH3Cl formation, instead catalyzing the over-oxidation of CH4 into CO2. Notably, the activity of the optimized TaOx/NaTaO3 photocatalyst surpasses that of reported noble metal photocatalysts. This research offers an effective strategy for enhancing the selectivity of photocatalytic methane chlorination using inorganic chlorine ions.

20.
Toxicol Appl Pharmacol ; 483: 116816, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38218207

RESUMEN

Phthalates (PEs), such as di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and butyl benzyl phthalate (BBP) could cause reproductive and developmental toxicities, while human beings are increasingly exposed to them at low-doses. Phytochemical quercetin (Que) is a flavonoid that has estrogenic effect, anti-inflammatory and anti-oxidant effects. This study was conducted to assess the alleviative effect of Que. on male reproductive toxicity induced by the mixture of three commonly used PEs (MPEs) at low-dose in rats, and explore the underlying mechanism. Male rats were treated with MPEs (16 mg/kg/day) and/or Que. (50 mg/kg/d) for 91 days. The results showed that MPEs exposure caused male reproductive injuries, such as decreased serum sex hormones levels, abnormal testicular pathological structure, increased abnormal sperm rate and changed expressions of PIWIL1 and PIWIL2. Furthermore, MPEs also changed the expression of steroidogenic proteins in steroid hormone metabolism, including StAR, CYP11A1, CYP17A1, 17ß-HSD, CYP19A1. However, the alterations of these parameters were reversed by Que. MPEs caused male reproductive injuries in rats; Que. inhibited MPEs' male reproductive toxicity, which might relate to the improvement of testosterone biosynthesis.


Asunto(s)
Dietilhexil Ftalato , Ácidos Ftálicos , Humanos , Ratas , Masculino , Animales , Quercetina/farmacología , Testosterona , Ratas Sprague-Dawley , Semen/metabolismo , Ácidos Ftálicos/toxicidad , Ácidos Ftálicos/metabolismo , Testículo , Dietilhexil Ftalato/toxicidad , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacología
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