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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32814014

RESUMEN

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Asunto(s)
Variación Genética/genética , Enfermedades por Picaduras de Garrapatas/microbiología , Garrapatas/genética , Animales , Línea Celular , Vectores de Enfermedades , Especificidad del Huésped/genética
2.
Cell ; 179(3): 736-749.e15, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31626772

RESUMEN

Underrepresentation of Asian genomes has hindered population and medical genetics research on Asians, leading to population disparities in precision medicine. By whole-genome sequencing of 4,810 Singapore Chinese, Malays, and Indians, we found 98.3 million SNPs and small insertions or deletions, over half of which are novel. Population structure analysis demonstrated great representation of Asian genetic diversity by three ethnicities in Singapore and revealed a Malay-related novel ancestry component. Furthermore, demographic inference suggested that Malays split from Chinese ∼24,800 years ago and experienced significant admixture with East Asians ∼1,700 years ago, coinciding with the Austronesian expansion. Additionally, we identified 20 candidate loci for natural selection, 14 of which harbored robust associations with complex traits and diseases. Finally, we show that our data can substantially improve genotype imputation in diverse Asian and Oceanian populations. These results highlight the value of our data as a resource to empower human genetics discovery across broad geographic regions.


Asunto(s)
Genética de Población , Genoma Humano/genética , Selección Genética , Secuenciación Completa del Genoma , Pueblo Asiatico/genética , Femenino , Genotipo , Humanos , Malasia/epidemiología , Masculino , Polimorfismo de Nucleótido Simple/genética , Singapur/epidemiología
3.
Plant Cell ; 35(6): 2271-2292, 2023 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-36916511

RESUMEN

Ethylene induces anthocyanin biosynthesis in most fruits, including apple (Malus domestica) and plum (Prunus spp.). By contrast, ethylene inhibits anthocyanin biosynthesis in pear (Pyrus spp.), but the underlying molecular mechanism remains unclear. In this study, we identified and characterized an ethylene-induced ETHYLENE RESPONSE FACTOR (ERF) transcription factor, PpETHYLENE RESPONSE FACTOR9 (PpERF9), which functions as a transcriptional repressor. Our analyses indicated PpERF9 can directly inhibit expression of the MYB transcription factor gene PpMYB114 by binding to its promoter. Additionally, PpERF9 inhibits the expression of the transcription factor gene PpRELATED TO APETALA2.4 (PpRAP2.4), which activates PpMYB114 expression, by binding to its promoter, thus forming a PpERF9-PpRAP2.4-PpMYB114 regulatory circuit. Furthermore, PpERF9 interacts with the co-repressor PpTOPLESS1 (PpTPL1) via EAR motifs to form a complex that removes the acetyl group on histone H3 and maintains low levels of acetylated H3 in the PpMYB114 and PpRAP2.4 promoter regions. The resulting suppressed expression of these 2 genes leads to decreased anthocyanin biosynthesis in pear. Collectively, these results indicate that ethylene inhibits anthocyanin biosynthesis by a mechanism that involves PpERF9-PpTPL1 complex-mediated histone deacetylation of PpMYB114 and PpRAP2.4. The data presented herein will be useful for clarifying the relationship between chromatin status and hormone signaling, with implications for plant biology research.


Asunto(s)
Malus , Pyrus , Pyrus/genética , Pyrus/metabolismo , Factores de Transcripción/metabolismo , Antocianinas/metabolismo , Histonas/metabolismo , Regulación de la Expresión Génica de las Plantas , Etilenos/metabolismo , Frutas/metabolismo , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(8): e2213272120, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36787367

RESUMEN

Macropinocytosis is an actin-dependent mode of nonselective endocytosis that mediates the uptake of extracellular fluid-phase cargoes. It is now well recognized that tumor cells exploit macropinocytosis to internalize macromolecules that can be catabolized and used to support cell growth and proliferation under nutrient-limiting conditions. Therefore, the identification of molecular mechanisms that control macropinocytosis is fundamental to the understanding of the metabolic adaptive landscape of tumor cells. Here, we report that the acetyl-CoA-producing enzyme, ATP citrate lyase (ACLY), is a key regulator of macropinocytosis and describes a heretofore-unappreciated association of ACLY with the actin cytoskeleton. The cytoskeletal tethering of ACLY is required for the spatially defined acetylation of heterodimeric actin capping protein, which we identify as an essential mediator of the actin remodeling events that drive membrane ruffling and macropinocytosis. Furthermore, we identify a requirement for mitochondrial-derived citrate, an ACLY substrate, for macropinocytosis, and show that mitochondria traffic to cell periphery regions juxtaposed to plasma membrane ruffles. Collectively, these findings establish a mode of metabolite compartmentalization that supports the spatiotemporal modulation of membrane-cytoskeletal interactions required for macropinocytosis by coupling regional acetyl-CoA availability with dynamic protein acetylation.


Asunto(s)
ATP Citrato (pro-S)-Liasa , Actinas , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/metabolismo , Acetilcoenzima A/metabolismo , Actinas/metabolismo , Procesamiento Proteico-Postraduccional , Proliferación Celular
5.
J Biol Chem ; : 107556, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39002683

RESUMEN

Diversity, a hallmark of G protein-coupled receptor (GPCR) signaling, partly stems from alternative splicing of a single gene generating more than one isoform for a receptor. Additionally, receptor responses to ligands can be attenuated by desensitization upon prolonged or repeated ligand exposure. Both phenomena have been demonstrated and exemplified by the deuterostome tachykinin (TK) signaling system, although the role of phosphorylation in desensitization remains a subject of debate. Here, we describe the signaling system for tachykinin-related peptides (TKRPs) in a protostome, mollusk Aplysia. We cloned the Aplysia TKRP precursor, which encodes three TKRPs (apTKRP-1, apTKRP-2a, and apTKRP-2b) containing the FXGXR-amide motif. In situ hybridization and immunohistochemistry showed predominant expression of TKRP mRNA and peptide in the cerebral ganglia. TKRPs and their post-translational modifications were observed in extracts of CNS ganglia using mass spectrometry. We identified two Aplysia TKRP receptors (TKRPRs), named apTKRPR-A and apTKRPR-B. These receptors are two isoforms generated through alternative splicing of the same gene and differ only in their intracellular C-termini. Structure-activity relationship analysis of apTKRP-2b revealed that both C-terminal amidation and conserved residues of the ligand are critical for receptor activation. C-terminal truncates and mutants of apTKRPRs suggested that there is a C-terminal phosphorylation-independent desensitization for both receptors. Moreover, apTKRPR-B also exhibits phosphorylation-dependent desensitization through the phosphorylation of C-terminal Ser/Thr residues. This comprehensive characterization of the Aplysia TKRP signaling system underscores the evolutionary conservation of the TKRP and TK signaling systems, while highlighting the intricacies of receptor regulation through alternative splicing and differential desensitization mechanisms.

6.
Plant J ; 119(2): 746-761, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38733631

RESUMEN

The jasmonic acid (JA) signaling pathway plays an important role in promoting the biosynthesis of tanshinones. While individual transcription factors have been extensively studied in the context of tanshinones biosynthesis regulation, the influence of methyl jasmonate (MeJA)-induced transcriptional complexes remains unexplored. This study elucidates the positive regulatory role of the basic helix-loop-helix protein SmMYC2 in tanshinones biosynthesis in Salvia miltiorrhiza. SmMYC2 not only binds to SmGGPPS1 promoters, activating their transcription, but also interacts with SmMYB36. This interaction enhances the transcriptional activity of SmMYC2 on SmGGPPS1, thereby promoting tanshinones biosynthesis. Furthermore, we identified three JA signaling repressors, SmJAZ3, SmJAZ4, and SmJAZ8, which interact with SmMYC2. These repressors hindered the transcriptional activity of SmMYC2 on SmGGPPS1 and disrupted the interaction between SmMYC2 and SmMYB36. MeJA treatment triggered the degradation of SmJAZ3 and SmJAZ4, allowing the SmMYC2-SmMYB36 complex to subsequently activate the expression of SmGGPPS1, whereas SmJAZ8 inhibited MeJA-mediated degradation due to the absence of the LPIARR motif. These results demonstrate that the SmJAZ-SmMYC2-SmMYB36 module dynamically regulates the JA-mediated accumulation of tanshinones. Our results reveal a new regulatory network for the biosynthesis of tanshinones. This study provides valuable insight for future research on MeJA-mediated modulation of tanshinones biosynthesis.


Asunto(s)
Abietanos , Acetatos , Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Oxilipinas , Proteínas de Plantas , Salvia miltiorrhiza , Ciclopentanos/metabolismo , Ciclopentanos/farmacología , Oxilipinas/metabolismo , Oxilipinas/farmacología , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo , Salvia miltiorrhiza/efectos de los fármacos , Acetatos/farmacología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Transducción de Señal , Regiones Promotoras Genéticas/genética
7.
Plant Physiol ; 194(3): 1794-1814, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38036294

RESUMEN

Bud dormancy is an important physiological process during winter. Its release requires a certain period of chilling. In pear (Pyrus pyrifolia), the abscisic acid (ABA)-induced expression of DORMANCY-ASSOCIATED MADS-box (DAM) genes represses bud break, whereas exogenous gibberellin (GA) promotes dormancy release. However, with the exception of ABA and GA, the regulatory effects of phytohormones on dormancy remain largely uncharacterized. In this study, we confirmed brassinosteroids (BRs) and jasmonic acid (JA) contribute to pear bud dormancy release. If chilling accumulation is insufficient, both 24-epibrassinolide (EBR) and methyl jasmonic acid (MeJA) can promote pear bud break, implying that they positively regulate dormancy release. BRASSINAZOLE RESISTANT 2 (BZR2), which is a BR-responsive transcription factor, inhibited PpyDAM3 expression and accelerated pear bud break. The transient overexpression of PpyBZR2 increased endogenous GA, JA, and JA-Ile levels. In addition, the direct interaction between PpyBZR2 and MYELOCYTOMATOSIS 2 (PpyMYC2) enhanced the PpyMYC2-mediated activation of Gibberellin 20-oxidase genes PpyGA20OX1L1 and PpyGA20OX2L2 transcription, thereby increasing GA3 contents and accelerating pear bud dormancy release. Interestingly, treatment with 5 µm MeJA increased the bud break rate, while also enhancing PpyMYC2-activated PpyGA20OX expression and increasing GA3,4 contents. The 100 µm MeJA treatment decreased the PpyMYC2-mediated activation of the PpyGA20OX1L1 and PpyGA20OX2L2 promoters and suppressed the inhibitory effect of PpyBZR2 on PpyDAM3 transcription, ultimately inhibiting pear bud break. In summary, our data provide insights into the crosstalk between the BR and JA signaling pathways that regulate the BZR2/MYC2-mediated pathway in the pear dormancy release process.


Asunto(s)
Brasinoesteroides , Ciclopentanos , Oxilipinas , Pyrus , Triazoles , Brasinoesteroides/farmacología , Pyrus/genética , Reguladores del Crecimiento de las Plantas/farmacología , Ácido Abscísico
8.
Nature ; 568(7753): 566-570, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30944472

RESUMEN

ATP-citrate lyase (ACLY) is a central metabolic enzyme and catalyses the ATP-dependent conversion of citrate and coenzyme A (CoA) to oxaloacetate and acetyl-CoA1-5. The acetyl-CoA product is crucial for the metabolism of fatty acids6,7, the biosynthesis of cholesterol8, and the acetylation and prenylation of proteins9,10. There has been considerable interest in ACLY as a target for anti-cancer drugs, because many cancer cells depend on its activity for proliferation2,5,11. ACLY is also a target against dyslipidaemia and hepatic steatosis, with a compound currently in phase 3 clinical trials4,5. Many inhibitors of ACLY have been reported, but most of them have weak activity5. Here we report the development of a series of low nanomolar, small-molecule inhibitors of human ACLY. We have also determined the structure of the full-length human ACLY homo-tetramer in complex with one of these inhibitors (NDI-091143) by cryo-electron microscopy, which reveals an unexpected mechanism of inhibition. The compound is located in an allosteric, mostly hydrophobic cavity next to the citrate-binding site, and requires extensive conformational changes in the enzyme that indirectly disrupt citrate binding. The observed binding mode is supported by and explains the structure-activity relationships of these compounds. This allosteric site greatly enhances the 'druggability' of ACLY and represents an attractive target for the development of new ACLY inhibitors.


Asunto(s)
ATP Citrato (pro-S)-Liasa/antagonistas & inhibidores , ATP Citrato (pro-S)-Liasa/ultraestructura , Compuestos de Bencilo/farmacología , Microscopía por Crioelectrón , Inhibidores Enzimáticos/farmacología , ATP Citrato (pro-S)-Liasa/química , ATP Citrato (pro-S)-Liasa/metabolismo , Adenosina Difosfato/metabolismo , Regulación Alostérica/efectos de los fármacos , Compuestos de Bencilo/química , Sitios de Unión/efectos de los fármacos , Ácido Cítrico/metabolismo , Inhibidores Enzimáticos/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Dominios Proteicos , Multimerización de Proteína , Relación Estructura-Actividad
9.
Nature ; 575(7782): 375-379, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31618756

RESUMEN

Mitochondrial homeostasis depends on mitophagy, the programmed degradation of mitochondria. Only a few proteins are known to participate in mitophagy. Here we develop a multidimensional CRISPR-Cas9 genetic screen, using multiple mitophagy reporter systems and pro-mitophagy triggers, and identify numerous components of parkin-dependent mitophagy1. Unexpectedly, we find that the adenine nucleotide translocator (ANT) complex is required for mitophagy in several cell types. Whereas pharmacological inhibition of ANT-mediated ADP/ATP exchange promotes mitophagy, genetic ablation of ANT paradoxically suppresses mitophagy. Notably, ANT promotes mitophagy independently of its nucleotide translocase catalytic activity. Instead, the ANT complex is required for inhibition of the presequence translocase TIM23, which leads to stabilization of PINK1, in response to bioenergetic collapse. ANT modulates TIM23 indirectly via interaction with TIM44, which regulates peptide import through TIM232. Mice that lack ANT1 show blunted mitophagy and consequent profound accumulation of aberrant mitochondria. Disease-causing human mutations in ANT1 abrogate binding to TIM44 and TIM23 and inhibit mitophagy. Together, our findings show that ANT is an essential and fundamental mediator of mitophagy in health and disease.


Asunto(s)
Mitofagia , Animales , Línea Celular , Ratones , Proteínas de Transporte de Membrana Mitocondrial/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Nucleótidos/metabolismo , Unión Proteica , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo
10.
Mol Cell ; 67(2): 214-227.e7, 2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28625552

RESUMEN

Circular RNAs (circRNAs) generated via back-splicing are enhanced by flanking complementary sequences. Expression levels of circRNAs vary under different conditions, suggesting participation of protein factors in their biogenesis. Using genome-wide siRNA screening that targets all human unique genes and an efficient circRNA expression reporter, we identify double-stranded RNA-binding domain containing immune factors NF90/NF110 as key regulators in circRNA biogenesis. NF90/NF110 promote circRNA production in the nucleus by associating with intronic RNA pairs juxtaposing the circRNA-forming exon(s); they also interact with mature circRNAs in the cytoplasm. Upon viral infection, circRNA expression is decreased, in part owing to the nuclear export of NF90/NF110 to the cytoplasm. Meanwhile, NF90/NF110 released from circRNP complexes bind to viral mRNAs as part of their functions in antiviral immune response. Our results therefore implicate a coordinated regulation of circRNA biogenesis and function by NF90/NF110 in viral infection.


Asunto(s)
Núcleo Celular/metabolismo , Proteínas del Factor Nuclear 90/metabolismo , Unión Proteica , ARN Mensajero/metabolismo , ARN Viral/metabolismo , ARN/biosíntesis , Virosis/metabolismo , Transporte Activo de Núcleo Celular , Núcleo Celular/efectos de los fármacos , Perfilación de la Expresión Génica , Células HEK293 , Células HeLa , Interacciones Huésped-Patógeno , Humanos , Proteínas del Factor Nuclear 90/genética , Proteínas del Factor Nuclear 90/inmunología , Poli I-C/farmacología , ARN/química , ARN/genética , Interferencia de ARN , Procesamiento Postranscripcional del ARN , Empalme del ARN , Estabilidad del ARN , ARN Circular , ARN Mensajero/genética , ARN Viral/genética , Transfección , Virosis/genética , Virosis/inmunología
11.
Nucleic Acids Res ; 51(14): 7691-7703, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37395400

RESUMEN

Construction of synthetic circuits that can reprogram genetic networks and signal pathways is a long-term goal for manipulation of biosystems. However, it is still highly challenging to build artificial genetic communications among endogenous RNA species due to their sequence independence and structural diversities. Here we report an RNA-based synthetic circuit that can establish regulatory linkages between expression of endogenous genes in both Escherichiacoli and mammalian cells. This design employs a displacement-assembly approach to modulate the activity of guide RNA for function control of CRISPR/Cas9. Our experiments demonstrate the great effectiveness of this RNA circuit for building artificial connections between expression of originally unrelated genes. Both exogenous and naturally occurring RNAs, including small/microRNAs and long mRNAs, are capable of controlling expression of another endogenous gene through this approach. Moreover, an artificial signal pathway inside mammalian cells is also successfully established to control cell apoptosis through our designed synthetic circuit. This study provides a general strategy for constructing synthetic RNA circuits, which can introduce artificial connections into the genetic networks of mammalian cells and alter the cellular phenotypes.


Asunto(s)
Sistemas CRISPR-Cas , MicroARNs , Animales , Sistemas CRISPR-Cas/genética , Genes Sintéticos , Redes Reguladoras de Genes/genética , ARN Mensajero , Edición Génica , Mamíferos/genética
12.
Anal Chem ; 96(5): 2117-2123, 2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38268109

RESUMEN

Despite the progress that has been made in diverse DNA-based nanodevices to in situ monitor the activity of the DNA repair enzymes in living cells, the significance of improving both the sensitivity and specificity has remained largely neglected and understudied. Herein, we propose a regulatable DNA nanodevice to specifically monitor the activity of DNA repair enzymes for early evaluation of cancer mediated by genomic instability. Concretely, an AND logic gate-regulated DNAzyme nanoflower was rationally designed by the self-assembly of the DNA duplex modified with both apurinic/apyrimidinic (AP) site and methyl lesion site. The DNAzyme nanoflower could be reconfigured under the repair of AP sites and O6-methylguanine sites by apurinic/apyrimidinic endonuclease 1 (APE1) and O6-methylguanine methyltransferase (MGMT) to produce a fluorescent signal, realizing the sensitive monitoring of the activity of APE1 and MGMT. Compared to the free DNAzyme duplex, the fluorescent response of the DNAzyme nanoflower increased by 60%, due to the effective enrichment of the DNA probes by the nanoflower structure. More importantly, we have demonstrated that the dual-enzyme activated strategy allows imaging of specific cancer cells in the AND logic gate manner using MCF-7 as a cancer cell model, improving the specificity of cancer cell imaging. This AND logic gate-regulated multifunctional DNAzyme nanoflower provides a simple tool for simultaneously visualizing multiple DNA repair enzymes, holding great potential in early clinical diagnosis and drug discovery.


Asunto(s)
Reparación del ADN , ADN Catalítico , Daño del ADN , Enzimas Reparadoras del ADN/genética , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , ADN/química
13.
Nat Methods ; 18(1): 51-59, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33288960

RESUMEN

Circular RNAs (circRNAs) produced from back-spliced exons are widely expressed, but individual circRNA functions remain poorly understood owing to the lack of adequate methods for distinguishing circRNAs from cognate messenger RNAs with overlapping exons. Here, we report that CRISPR-RfxCas13d can effectively discriminate circRNAs from mRNAs by using guide RNAs targeting sequences spanning back-splicing junction (BSJ) sites featured in RNA circles. Using a lentiviral library that targets sequences across BSJ sites of highly expressed human circRNAs, we show that a group of circRNAs are important for cell growth mostly in a cell-type-specific manner and that a common oncogenic circRNA, circFAM120A, promotes cell proliferation by preventing the mRNA for family with sequence similarity 120A (FAM120A) from binding the translation inhibitor IGF2BP2. Further application of RfxCas13d-BSJ-gRNA screening has uncovered circMan1a2, which has regulatory potential in mouse embryo preimplantation development. Together, these results establish CRISPR-RfxCas13d as a useful tool for the discovery and functional study of circRNAs at both individual and large-scale levels.


Asunto(s)
Sistemas CRISPR-Cas , Neoplasias del Colon/patología , Regulación Neoplásica de la Expresión Génica , ARN Circular/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Empalme Alternativo , Animales , Apoptosis , Proliferación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
14.
RNA ; 28(11): 1534-1541, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36130077

RESUMEN

The polyadenylation signal (PAS) is a key sequence element for 3'-end cleavage and polyadenylation of messenger RNA precursors (pre-mRNAs). This hexanucleotide motif is recognized by the mammalian polyadenylation specificity factor (mPSF), consisting of CPSF160, WDR33, CPSF30, and Fip1 subunits. Recent studies have revealed how the AAUAAA PAS, the most frequently observed PAS, is recognized by mPSF. We report here the structure of human mPSF in complex with the AUUAAA PAS, the second most frequently identified PAS. Conformational differences are observed for the A1 and U2 nucleotides in AUUAAA compared to the A1 and A2 nucleotides in AAUAAA, while the binding modes of the remaining 4 nt are essentially identical. The 5' phosphate of U2 moves by 2.6 Å and the U2 base is placed near the six-membered ring of A2 in AAUAAA, where it makes two hydrogen bonds with zinc finger 2 (ZF2) of CPSF30, which undergoes conformational changes as well. We also attempted to determine the binding modes of two rare PAS hexamers, AAGAAA and GAUAAA, but did not observe the RNA in the cryo-electron microscopy density. The residues in CPSF30 (ZF2 and ZF3) and WDR33 that recognize PAS are disordered in these two structures.


Asunto(s)
Poliadenilación , Factores de Escisión y Poliadenilación de ARNm , Animales , Humanos , Factores de Escisión y Poliadenilación de ARNm/genética , Factores de Escisión y Poliadenilación de ARNm/metabolismo , Factor de Especificidad de Desdoblamiento y Poliadenilación/metabolismo , Microscopía por Crioelectrón , ARN Mensajero/metabolismo , Unión Proteica , Precursores del ARN/metabolismo , Mamíferos/genética , Nucleótidos/metabolismo , Poli A/metabolismo
15.
Opt Lett ; 49(6): 1437-1440, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489419

RESUMEN

A high-performance 5-junction cascade quantum dot (QD) vertical cavity surface-emitting laser (VCSEL) with 1.3 µm wavelength was designed. The characteristics of the QD as active regions and tunnel junctions are combined to effectively increase output power. The photoelectric characteristics of single-junction, 3-junction cascade, and 5-junction cascade QD VCSELs are compared at continuous-wave conditions. Results indicate that the threshold current gradually decreases, and the output power and slope efficiency exponential increase with the increase of the number of active regions. The peak power conversion efficiency of 58.4% is achieved for the 5-junction cascade individual QD VCSEL emitter with 10 µm oxide aperture. The maximum slope efficiency of the device is 6.27 W/A, which is approximately six times than that of the single-junction QD VCSEL. The output power of the 5-junction cascade QD VCSEL reaches 188.13 mW at injection current 30 mA. High-performance multi-junction cascade 1.3-µm QD VCSEL provides data and theoretical support for the preparation of epitaxial materials.

16.
Cytotherapy ; 26(5): 456-465, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38385909

RESUMEN

BACKGROUND AIMS: The combination therapy of autologous hematopoietic stem cell transplantation (ASCT) and chimeric antigen receptor T-cell (CART) therapy has been employed to improve outcomes for relapsed or refractory (R/R) B-cell non-Hodgkin-lymphoma (B-NHL). The widely used conditioning regimen before ASCT plus CART therapy reported in the literature was carmustine, etoposide, cytarabine and melphalan (BEAM). However, whether adding fludarabine to the BEAM regimen (BEAMF) can improve the survival of patients with R/R B-NHL remains unknown. METHODS: In total, 39 and 19 patients with R/R B-NHL were enrolled to compare clinical outcomes in the BEAM and BEAMF regimens before ASCT plus CD19/22 CART therapy, respectively. RESULTS: The objective response (OR) rates at 3 months to BEAM and BEAMF regimens before ASCT plus CD19/22 CART therapy were 71.8% and 94.7%, respectively (P = 0.093). The BEAMF regimen showed a trend towards a superior duration of response compared with the BEAM regimen (P = 0.09). After a median follow-up of 28 months (range: 0.93-51.9 months), the BEAMF regimen demonstrated superior 2-year progression-free survival (PFS) (89.5% versus 63.9%; P = 0.048) and 2-year overall survival (OS) (100% vs 77.3%; P = 0.035) compared with the BEAM regimen. In the multivariable Cox regression analysis, OR at month 3 (responders) was remarkably correlated with better OS (hazard ratio: 0.112, P = 0.005) compared with OR (non-responders). CONCLUSIONS: For patients with R/R B-NHL, the BEAMF regimen before ASCT plus CD19/22 CART therapy was correlated with superior PFS and OS than the BEAM regimen, and the BEAMF regimen is a promising alternative conditioning regimen for ASCT plus CAR-T therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Carmustina , Citarabina , Etopósido , Trasplante de Células Madre Hematopoyéticas , Melfalán , Trasplante Autólogo , Vidarabina , Vidarabina/análogos & derivados , Humanos , Masculino , Carmustina/uso terapéutico , Carmustina/administración & dosificación , Melfalán/uso terapéutico , Melfalán/administración & dosificación , Citarabina/uso terapéutico , Citarabina/administración & dosificación , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Persona de Mediana Edad , Adulto , Trasplante Autólogo/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Etopósido/uso terapéutico , Etopósido/administración & dosificación , Vidarabina/administración & dosificación , Vidarabina/uso terapéutico , Pronóstico , Anciano , Linfoma de Células B/terapia , Linfoma de Células B/mortalidad , Podofilotoxina/uso terapéutico , Podofilotoxina/administración & dosificación , Inmunoterapia Adoptiva/métodos , Adulto Joven , Terapia Combinada , Acondicionamiento Pretrasplante/métodos , Receptores Quiméricos de Antígenos/uso terapéutico
17.
BMC Cancer ; 24(1): 445, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38600469

RESUMEN

BACKGROUND: Proprotein convertase subtilisin/kexin type 9 (PCSK9), the last member of the proprotein convertase family, functions as a classic regulator of low-density lipoprotein (LDL) by interacting with low-density lipoprotein receptor (LDLR). Recent studies have shown that PCSK9 can affect the occurrence and development of tumors and can be used as a novel therapeutic target. However, a comprehensive pan-cancer analysis of PCSK9 has yet to be conducted. METHODS: The potential oncogenic effects of PCSK9 in 33 types of tumors were explored based on the datasets of The Cancer Genome Atlas (TCGA) dataset. In addition, the immune regulatory role of PCSK9 inhibition was evaluated via in vitro cell coculture and the tumor-bearing mouse model. Finally, the antitumor efficacy of targeted PCSK9 combined with OVA-II vaccines was verified. RESULTS: Our results indicated that PCSK9 was highly expressed in most tumor types and was significantly correlated with late disease stage and poor prognosis. Additionally, PCSK9 may regulate the tumor immune matrix score, immune cell infiltration, immune checkpoint expression, and major histocompatibility complex expression. Notably, we first found that dendritic cell (DC) infiltration and major histocompatibility complex-II (MHC-II) expression could be upregulated by PCSK9 inhibition and improve CD8+ T cell activation in the tumor immune microenvironment, thereby achieving potent tumor control. Combining PCSK9 inhibitors could enhance the efficacies of OVA-II tumor vaccine monotherapy. CONCLUSIONS: Conclusively, our pan-cancer analysis provided a more comprehensive understanding of the oncogenic and immunoregulatory roles of PCSK9 and demonstrated that targeting PCSK9 could increase the efficacy of long peptide vaccines by upregulating DC infiltration and MHC-II expression on the surface of tumor cells. This study reveals the critical oncogenic and immunoregulatory roles of PCSK9 in various tumors and shows the promise of PCSK9 as a potent immunotherapy target.


Asunto(s)
Genes MHC Clase II , Inmunoterapia , Neoplasias , Proproteína Convertasa 9 , Proproteína Convertasas , Animales , Ratones , Antígenos de Histocompatibilidad , Lipoproteínas LDL , Neoplasias/genética , Neoplasias/terapia , Proproteína Convertasa 9/metabolismo , Proproteína Convertasas/antagonistas & inhibidores , Receptores de LDL/genética , Microambiente Tumoral
18.
Int Arch Allergy Immunol ; 185(7): 718-728, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38513629

RESUMEN

INTRODUCTION: The purpose of this study was to assess the clinical effectiveness and safety profile of omalizumab as a therapeutic intervention for chronic urticaria (CU). METHODS: From March 1, 2023, to September 30, 2023, data on a cohort comprising 96 patients with CU, who underwent treatment with omalizumab at our medical institution's allergy clinic, were systematically compiled. Subsequent to the administration of omalizumab, the therapeutic efficacy was assessed utilizing the 7-day urticaria activity score and the urticaria control test. RESULTS: Based on the statistical analysis, the mean duration of therapeutic intervention was 2.4 ± 1.3 months, with a corresponding mean cumulative dosage of 765 ± 450 mg. Of the subset of 42 patients with CU who were subjected to a follow-up period exceeding 3 months, it was observed that the treatment led to complete symptom remission, and no instances of recurrence were documented. Notably, there were statistically significant differences in the treatment duration and the cumulative dosage between patients who experienced co-morbid conditions and those who did not (p < 0.01, 95% CI: 0.280-1.326; p < 0.01, 95% CI: 0.597-2.997). Furthermore, there were significant differences in the treatment duration and cumulative dosage between patients in the combined allergic rhinitis group and those in the non-combined allergic rhinitis group (p < 0.01, 95% CI: 0.204-1.305; p = 0.01, 95% CI: 0.326-2.860). CONCLUSION: Omalizumab demonstrates efficacy in the management of CU among Chinese patients by exerting effective symptom control and facilitating the regression of skin lesions. The assessment of its therapeutic efficacy typically requires a 12-week treatment period. Moreover, the co-occurrence of CU with other allergic disorders serves as a pertinent consideration for the adjustment of omalizumab dosing regimens.


Asunto(s)
Antialérgicos , Urticaria Crónica , Omalizumab , Humanos , Omalizumab/uso terapéutico , Urticaria Crónica/tratamiento farmacológico , Femenino , Masculino , Adulto , Persona de Mediana Edad , Resultado del Tratamiento , Antialérgicos/uso terapéutico , Adulto Joven
19.
Langmuir ; 40(28): 14291-14302, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38950193

RESUMEN

The key to enhancing water electrolysis efficiency lies in selecting highly efficient catalysts. Currently, high-entropy alloys (HEAs) are utilized in electrocatalysis applications owing to their diverse elemental composition, disordered elemental distribution, and the high solubility of each element, endowing them with excellent catalytic performance. The experiments were conducted using isoatomic FeNiCrMo HEA as a precursor, with a high-activity three-dimensional nanoporous structure rapidly synthesized via electrochemical one-step dealloying in a choline chloride-thiourea (ChCl-TU) deep eutectic solvent (DES). The results indicate that the dealloyed Fe20Co20Ni20Cr20Mo20 HEA mainly consists of two phases: face-centered cubic and σ phases. The imbalance in the distribution of elements in these two phases leads to quite different corrosion speeds with the FCC phase being preferentially corroded. Furthermore, synergistic electron coupling between surface atoms in the three-dimensional nanoporous structure strengthens the behavior of the oxygen evolution reaction (OER). At a current density of 40 mA cm-2, the overpotential after dealloying decreased to 370 mV, demonstrating excellent stability. The technique demonstrated in this work provides a novel approach to improve the catalytic activity of OER.

20.
Mol Cell Biochem ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38782835

RESUMEN

Thioredoxin reductase (TrxR) is a pivotal regulator of redox homeostasis. It is frequently overexpressed in various cancer cells, including prostate cancer, making it a promising target for the development of anti-cancer drugs. In this study, we screened a series of newly designed complexes of gold(I) phosphine. Specifically, Compound 5 exhibited the highest cytotoxicity against prostate cancer cells and demonstrated stronger antitumor effects than commonly used drugs, such as cisplatin and auranofin. Importantly, our mechanistic study revealed that Compound 5 effectively inhibits the TrxR system in vitro. Additionally, Compound 5 promoted intracellular accumulation of reactive oxygen species (ROS), leading to mitochondrial dysfunction and irreversible apoptosis in prostate cancer cells. Our in vivo xenograft study further demonstrated that Compound 5 has excellent antitumor activity against prostate cancer cells, but does not cause severe side effects. These findings provide a promising lead Compound for the development of novel antitumor agents targeting prostate cancer and offer a valuable tool for investigating biological pathways involving TrxR and ROS modulation.

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