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1.
Cell ; 185(22): 4049-4066.e25, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36208623

RESUMO

Blocking PD-1/PD-L1 signaling transforms cancer therapy and is assumed to unleash exhausted tumor-reactive CD8+ T cells in the tumor microenvironment (TME). However, recent studies have also indicated that the systemic tumor-reactive CD8+ T cells may respond to PD-1/PD-L1 immunotherapy. These discrepancies highlight the importance of further defining tumor-specific CD8+ T cell responders to PD-1/PD-L1 blockade. Here, using multiple preclinical tumor models, we revealed that a subset of tumor-specific CD8+ cells in the tumor draining lymph nodes (TdLNs) was not functionally exhausted but exhibited canonical memory characteristics. TdLN-derived tumor-specific memory (TTSM) cells established memory-associated epigenetic program early during tumorigenesis. More importantly, TdLN-TTSM cells exhibited superior anti-tumor therapeutic efficacy after adoptive transfer and were characterized as bona fide responders to PD-1/PD-L1 blockade. These findings highlight that TdLN-TTSM cells could be harnessed to potentiate anti-tumor immunotherapy.


Assuntos
Antígeno B7-H1 , Neoplasias , Humanos , Receptor de Morte Celular Programada 1 , Linfócitos T CD8-Positivos , Inibidores de Checkpoint Imunológico , Microambiente Tumoral , Neoplasias/terapia , Neoplasias/patologia , Linfonodos/patologia
2.
Mol Cell ; 82(8): 1528-1542.e10, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35245436

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a global health concern with no approved drugs. High-protein dietary intervention is currently the most effective treatment. However, its underlying mechanism is unknown. Here, using Drosophila oenocytes, the specialized hepatocyte-like cells, we find that dietary essential amino acids ameliorate hepatic steatosis by inducing polyubiquitination of Plin2, a lipid droplet-stabilizing protein. Leucine and isoleucine, two branched-chain essential amino acids, strongly bind to and activate the E3 ubiquitin ligase Ubr1, targeting Plin2 for degradation. We further show that the amino acid-induced Ubr1 activity is necessary to prevent steatosis in mouse livers and cultured human hepatocytes, providing molecular insight into the anti-NAFLD effects of dietary protein/amino acids. Importantly, split-intein-mediated trans-splicing expression of constitutively active UBR2, an Ubr1 family member, significantly ameliorates obesity-induced and high fat diet-induced hepatic steatosis in mice. Together, our results highlight activation of Ubr1 family proteins as a promising strategy in NAFLD treatment.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Aminoácidos Essenciais/metabolismo , Aminoácidos Essenciais/farmacologia , Aminoácidos Essenciais/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Hepatócitos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ubiquitinação
3.
Development ; 151(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38646855

RESUMO

Ecdysone-induced protein 93 (E93), known as the 'adult-specifier' transcription factor in insects, triggers metamorphosis in both hemimetabolous and holometabolous insects. Although E93 is conserved in ametabolous insects, its spatiotemporal expression and physiological function remain poorly understood. In this study, we first discover that, in the ametabolous firebrat Thermobia domestica, the previtellogenic ovary exhibits cyclically high E93 expression, and E93 mRNA is broadly distributed in previtellogenic ovarioles. E93 homozygous mutant females of T. domestica exhibit severe fecundity deficiency due to impaired previtellogenic development of the ovarian follicles, likely because E93 induces the expression of genes involved in ECM (extracellular matrix)-receptor interactions during previtellogenesis. Moreover, we reveal that in the hemimetabolous cockroach Blattella germanica, E93 similarly promotes previtellogenic ovarian development. In addition, E93 is also essential for vitellogenesis that is necessary to guarantee ovarian maturation and promotes the vitellogenesis-previtellogenesis switch in the fat body of adult female cockroaches. Our findings deepen the understanding of the roles of E93 in controlling reproduction in insects, and of E93 expression and functional evolution, which are proposed to have made crucial contributions to the origin of insect metamorphosis.


Assuntos
Metamorfose Biológica , Ovário , Reprodução , Animais , Feminino , Reprodução/genética , Metamorfose Biológica/genética , Ovário/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Vitelogênese/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/genética
4.
Proc Natl Acad Sci U S A ; 121(17): e2314353121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38635634

RESUMO

Auxin regulates plant growth and development through downstream signaling pathways, including the best-known SCFTIR1/AFB-Aux/IAA-ARF pathway and several other less characterized "noncanonical" pathways. Recently, one SCFTIR1/AFB-independent noncanonical pathway, mediated by Transmembrane Kinase 1 (TMK1), was discovered through the analyses of its functions in Arabidopsis apical hook development. Asymmetric accumulation of auxin on the concave side of the apical hook triggers DAR1-catalyzed release of the C-terminal of TMK1, which migrates into the nucleus, where it phosphorylates and stabilizes IAA32/34 to inhibit cell elongation, which is essential for full apical hook formation. However, the molecular factors mediating IAA32/34 degradation have not been identified. Here, we show that proteins in the CYTOKININ INDUCED ROOT WAVING 1 (CKRW1)/WAVY GROWTH 3 (WAV3) subfamily act as E3 ubiquitin ligases to target IAA32/34 for ubiquitination and degradation, which is inhibited by TMK1c-mediated phosphorylation. This antagonistic interaction between TMK1c and CKRW1/WAV3 subfamily E3 ubiquitin ligases regulates IAA32/34 levels to control differential cell elongation along opposite sides of the apical hook.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Transdução de Sinais , Ubiquitinas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas F-Box/genética , Proteínas F-Box/metabolismo
5.
Nature ; 577(7788): 79-84, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853069

RESUMO

Water lilies belong to the angiosperm order Nymphaeales. Amborellales, Nymphaeales and Austrobaileyales together form the so-called ANA-grade of angiosperms, which are extant representatives of lineages that diverged the earliest from the lineage leading to the extant mesangiosperms1-3. Here we report the 409-megabase genome sequence of the blue-petal water lily (Nymphaea colorata). Our phylogenomic analyses support Amborellales and Nymphaeales as successive sister lineages to all other extant angiosperms. The N. colorata genome and 19 other water lily transcriptomes reveal a Nymphaealean whole-genome duplication event, which is shared by Nymphaeaceae and possibly Cabombaceae. Among the genes retained from this whole-genome duplication are homologues of genes that regulate flowering transition and flower development. The broad expression of homologues of floral ABCE genes in N. colorata might support a similarly broadly active ancestral ABCE model of floral organ determination in early angiosperms. Water lilies have evolved attractive floral scents and colours, which are features shared with mesangiosperms, and we identified their putative biosynthetic genes in N. colorata. The chemical compounds and biosynthetic genes behind floral scents suggest that they have evolved in parallel to those in mesangiosperms. Because of its unique phylogenetic position, the N. colorata genome sheds light on the early evolution of angiosperms.


Assuntos
Genoma de Planta , Nymphaea/genética , Filogenia , Flores/genética , Flores/metabolismo , Nymphaea/metabolismo , Odorantes/análise
6.
Gastroenterology ; 167(5): 993-1007, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38906512

RESUMO

BACKGROUND & AIMS: Portal hypertension (PH) is one of the most frequent complications of chronic liver disease. The peripheral 5-hydroxytryptamine (5-HT) level was increased in cirrhotic patients. We aimed to elucidate the function and mechanism of 5-HT receptor 1A (HTR1A) in the portal vein (PV) on PH. METHODS: PH models were induced by thioacetamide injection, bile duct ligation, or partial PV ligation. HTR1A expression was detected using real-time polymerase chain reaction, in situ hybridization, and immunofluorescence staining. In situ intraportal infusion was used to assess the effects of 5-HT, the HTR1A agonist 8-OH-DPAT, and the HTR1A antagonist WAY-100635 on portal pressure (PP). Htr1a-knockout (Htr1a-/-) rats and vascular smooth muscle cell (VSMC)-specific Htr1a-knockout (Htr1aΔVSMC) mice were used to confirm the regulatory role of HTR1A on PP. RESULTS: HTR1A expression was significantly increased in the hypertensive PV of PH model rats and cirrhotic patients. Additionally, 8-OH-DPAT increased, but WAY-100635 decreased, the PP in rats without affecting liver fibrosis and systemic hemodynamics. Furthermore, 5-HT or 8-OH-DPAT directly induced the contraction of isolated PVs. Genetic deletion of Htr1a in rats and VSMC-specific Htr1a knockout in mice prevented the development of PH. Moreover, 5-HT triggered adenosine 3',5'-cyclic monophosphate pathway-mediated PV smooth muscle cell contraction via HTR1A in the PV. We also confirmed alverine as an HTR1A antagonist and demonstrated its capacity to decrease PP in rats with thioacetamide-, bile duct ligation-, and partial PV ligation-induced PH. CONCLUSIONS: Our findings reveal that 5-HT promotes PH by inducing the contraction of the PV and identify HTR1A as a promising therapeutic target for attenuating PH. As an HTR1A antagonist, alverine is expected to become a candidate for clinical PH treatment.


Assuntos
Hipertensão Portal , Camundongos Knockout , Pressão na Veia Porta , Veia Porta , Receptor 5-HT1A de Serotonina , Agonistas do Receptor 5-HT1 de Serotonina , Animais , Feminino , Humanos , Masculino , Camundongos , Ratos , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , AMP Cíclico/metabolismo , Modelos Animais de Doenças , Hipertensão Portal/metabolismo , Hipertensão Portal/genética , Hipertensão Portal/fisiopatologia , Hipertensão Portal/etiologia , Ligadura , Cirrose Hepática/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/patologia , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/fisiopatologia , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Piperazinas/farmacologia , Pressão na Veia Porta/efeitos dos fármacos , Veia Porta/metabolismo , Piridinas/farmacologia , Ratos Sprague-Dawley , Ratos Wistar , Receptor 5-HT1A de Serotonina/metabolismo , Receptor 5-HT1A de Serotonina/genética , Serotonina/metabolismo , Serotonina/farmacologia , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Transdução de Sinais , Tioacetamida/toxicidade
7.
FASEB J ; 38(3): e23458, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38315453

RESUMO

Diabetic kidney disease (DKD), a major microvascular complication of diabetes, is characterized by its complex pathogenesis, high risk of chronic renal failure, and lack of effective diagnosis and treatment methods. GSK3ß (glycogen synthase kinase 3ß), a highly conserved threonine/serine kinase, was found to activate glycogen synthase. As a key molecule of the glucose metabolism pathway, GSK3ß participates in a variety of cellular activities and plays a pivotal role in multiple diseases. However, these effects are not only mediated by affecting glucose metabolism. This review elaborates on the role of GSK3ß in DKD and its damage mechanism in different intrinsic renal cells. GSK3ß is also a biomarker indicating the progression of DKD. Finally, the protective effects of GSK3ß inhibitors on DKD are also discussed.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Glicogênio Sintase Quinase 3 beta , Humanos , Nefropatias Diabéticas/tratamento farmacológico , Glucose/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Rim/metabolismo
8.
Cell Mol Life Sci ; 81(1): 344, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133273

RESUMO

Osteogenesis is tightly coupled with angiogenesis spatiotemporally. Previous studies have demonstrated that type H blood vessel formed by endothelial cells with high expression of CD31 and Emcn (CD31hi Emcnhi ECs) play a crucial role in bone regeneration. The mechanism of the molecular communication around CD31hi Emcnhi ECs and bone mesenchymal stem cells (BMSCs) in the osteogenic microenvironment is unclear. This study indicates that exosomes from bone mesenchymal stem cells with 7 days osteogenic differentiation (7D-BMSCs-exo) may promote CD31hi Emcnhi ECs angiogenesis, which was verified by tube formation assay, qRT-PCR, Western blot, immunofluorescence staining and µCT assays etc. in vitro and in vivo. Furthermore, by exosomal miRNA microarray and WGCNA assays, we identified downregulated miR-150-5p as the most relative hub gene coupling osteogenic differentiation and type H blood vessel angiogenesis. With bioinformatics assays, dual luciferase reporter experiments, qRT-PCR and Western blot assays, SOX2(SRY-Box Transcription Factor 2) was confirmed as a novel downstream target gene of miR-150-5p in exosomes, which might be a pivotal mechanism regulating CD31hi Emcnhi ECs formation. Additionally, JC-1 immunofluorescence staining, Western blot and seahorse assay results showed that the overexpression of SOX2 could shift metabolic reprogramming from oxidative phosphorylation (OXPHOS) to glycolysis to enhance the CD31hi Emcnhi ECs formation. The PI3k/Akt signaling pathway might play a key role in this process. In summary, BMSCs in osteogenic differentiation might secrete exosomes with low miR-150-5p expression to induce type H blood vessel formation by mediating SOX2 overexpression in ECs. These findings might reveal a molecular mechanism of osteogenesis coupled with type H blood vessel angiogenesis in the osteogenic microenvironment and provide a new therapeutic target or cell-free remedy for osteogenesis impaired diseases.


Assuntos
Diferenciação Celular , Células Endoteliais , Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Neovascularização Fisiológica , Osteogênese , MicroRNAs/genética , MicroRNAs/metabolismo , Exossomos/metabolismo , Osteogênese/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Diferenciação Celular/genética , Neovascularização Fisiológica/genética , Animais , Células Endoteliais/metabolismo , Células Endoteliais/citologia , Camundongos , Humanos , Células Cultivadas , Transdução de Sinais , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição SOXB1/genética , Reprogramação Metabólica , Angiogênese
9.
BMC Biol ; 22(1): 232, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39394161

RESUMO

BACKGROUND: Juvenile hormone (JH) is an insect-exclusive hormone involved in regulating diverse aspects of insect physiology, and the evolution of its diverse function is widely interesting. Studying embryogenesis in basal wingless insects is important to understand the functional evolution of JH; however, experimental studies in this regard are scarce. In this study, we conducted CRISPR/Cas9-mediated knockout (KO) of genes involved in JH biosynthesis and signaling cascades in the ametabolous firebrat, Thermobia domestica. Additionally, we investigated whether the primitive action of JH is conserved in the hemimetabolous cricket, Gryllus bimaculatus. RESULTS: We observed that KO of JHAMT, CYP15A1, Met, and Kr-h1 resulted in embryonic lethality in T. domestica. Deprivation of JH or JH signaling arrested the progression of extraembryonic fluid resorption after dorsal closure and hatching, which is consistent with the gene expression pattern showing high Kr-h1 expression in the late embryos of T. domestica. The embryos deficient in JH signaling displayed wrinkled and weak legs. Comparative transcriptome analysis revealed that JH signaling promotes embryonic leg maturation through inducing energy supply and muscle activity, as validated by transmission electron microscopy (TEM). In addition, JH signaling exhibited similar embryonic effects in G. bimaculatus. CONCLUSIONS: This study reveals the indispensable role of JH signaling in facilitating the maturation of terminal tissues during late embryogenesis, as demonstrated by the regulation of leg development, in ametabolous and hemimetabolous insects. These findings further indicate that the embryonic functions of JH evolved earlier than its anti-metamorphic functions during postembryonic development.


Assuntos
Desenvolvimento Embrionário , Hormônios Juvenis , Transdução de Sinais , Animais , Hormônios Juvenis/metabolismo , Desenvolvimento Embrionário/genética , Gryllidae/embriologia , Gryllidae/genética , Gryllidae/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Regulação da Expressão Gênica no Desenvolvimento , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo
10.
Nano Lett ; 24(23): 7012-7018, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38820129

RESUMO

Light management is critical to maximizing the external quantum efficiency of perovskite light-emitting diodes (PeLEDs), but strategies for enhancing light out-coupling are typically complex and expensive. Here, using a facile solvent treatment strategy, we create a layer of lithium fluoride (LiF) nanoislands that serve as a template to reconstruct the light-extracting interfaces for PeLEDs. The nanoisland interface rearranges the near-field light distribution in order to maximize the efficiency of internal light extraction. With the proper adjustment of the nanoisland size and distribution, we have achieved an optimal balance between charge injection and light out-coupling, resulting in bright, pure-red quasi-two-dimensional PeLEDs with a 21.8% peak external quantum efficiency.

11.
Nano Lett ; 24(13): 3952-3960, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38527956

RESUMO

Despite light-emitting diodes (LEDs) based on quasi-two-dimensional (Q-2D) perovskites being inexpensive and exhibiting high performance, defects still limit the improvement of electroluminescence efficiency and stability by causing nonradiative recombination. Here, an organic molecule, 1-(o-tolyl) biguanide, is used to simultaneously inhibit and passivate defects of Q-2D perovskites via in situ synchronous crystallization. This molecule not only prevents surface bromine vacancies from forming through hydrogen bonding with the bromine of intermediaries but also passivates surface defects through its interaction with uncoordinated Pb. Via combination of defect inhibition and passivation, the trap density of Q-2D perovskite films can be significantly reduced, and the emission efficiency of the film can be improved. Consequently, the corresponding LED shows an external quantum efficiency of 24.3%, and its operational stability has been increased nearly 15 times.

12.
J Neurosci ; 43(28): 5172-5179, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37225436

RESUMO

It is generally assumed that frequency selectivity varies along the cochlea. For example, at the base of the cochlea, which is a region sensitive to high-frequency sounds, the best frequency of a cochlear location increases toward the most basal end, that is, near the stapes. Response phases also vary along cochlear locations. At any given frequency, there is a decrease in phase lag toward the stapes. This tonotopic arrangement in the cochlea was originally described by Georg von Békésy in a seminal series of experiments on human cadavers and has been confirmed in more recent works on live laboratory animals. Nonetheless, our knowledge of tonotopy at the apex of the cochlea remains incomplete in animals with low-frequency hearing, which is relevant to human speech. The results of our experiments on guinea pig, gerbil, and chinchilla cochleas, regardless of the sex of the animal, show that responses to sound differ at locations across the apex in a pattern consistent with previous studies of the base of the cochlea.SIGNIFICANCE STATEMENT Tonotopy is an important property of the auditory system that has been shown to exist in many auditory centers. In fact, most auditory implants work on the assumption of its existence by assigning different frequencies to different stimulating electrodes based on their location. At the level of the basilar membrane in the cochlea, a tonotopic arrangement implies that high-frequency stimuli evoke largest displacements at the base, near the ossicles, and low-frequency sounds have their greatest effects at the apex. Although tonotopy has been confirmed at the base of the cochlea on live animals at the apex of the cochlea, however, it has been less studied. Here, we show that a tonotopic arrangement does exist at the apex of the cochlea.


Assuntos
Cóclea , Audição , Animais , Humanos , Cobaias , Cóclea/fisiologia , Audição/fisiologia , Som , Gerbillinae , Chinchila
13.
J Cell Mol Med ; 28(8): e18291, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38597412

RESUMO

Natural immunoglobulin M (IgM) antibodies have been shown to recognize post-ischemic neoepitopes following reperfusion of tissues and to activate complement. Specifically, IgM antibodies and complement have been shown to drive hepatic ischemia reperfusion injury (IRI). Herein, we investigate the therapeutic effect of C2 scFv (single-chain antibody construct with specificity of a natural IgM antibody) on hepatic IRI in C57BL/6 mice. Compared with PBS-treated mice, C2 scFv-treated mice displayed almost no necrotic areas, significant reduction in serum ALT, AST and LDH levels, and significantly reduced in the number of TUNEL positive cells. Moreover, C2 scFv-treated mice exhibited a notable reduction in inflammatory cells after hepatic IRI than PBS-treated mice. The serum IL-6, IL-1ß, TNF-α and MPC-1 levels were also severely suppressed by C2 scFv. Interestingly, C2 scFv reconstituted hepatic inflammation and IRI in Rag1-/- mice. We found that C2 scFv promoted hepatic cell death and increased inflammatory cytokines and infiltration of inflammatory cells after hepatic IRI in Rag1-/- mice. In addition, IgM and complement 3d (C3d) were deposited in WT mice and in Rag1-/- mice reconstituted with C2 scFv, indicating that C2 scFv can affect IgM binding and complement activation and reconstitute hepatic IRI. C3d expression was significantly lower in C57BL/6 mice treated with C2 scFv compared to PBS, indicating that excessive exogenous C2 scFv inhibited complement activation. These data suggest that C2 scFv alleviates hepatic IRI by blocking complement activation, and treatment with C2 scFv may be a promising therapy for hepatic IRI.


Assuntos
Fígado , Traumatismo por Reperfusão , Animais , Camundongos , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Imunoglobulina M , Proteínas do Sistema Complemento , Proteínas de Homeodomínio/metabolismo
14.
J Am Chem Soc ; 146(7): 4402-4411, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38329936

RESUMO

Fluorogenic RNA aptamers are valuable tools for cell imaging, but they still suffer from shortcomings such as easy degradation, limited photostability, and low fluorescence enhancement. Molecular crowding conditions enable the stabilization of the structure, promotion of folding, and improvement of activity of functional RNA. Based on artificial RNA condensates, here we present a versatile platform to improve fluorogenic RNA aptamer properties and develop sensors for target analyte imaging in living cells. Using the CUG repeat as a general tag to drive phase separation, various fluorogenic aptamer-based RNA condensates (FLARE) were prepared. We show that the molecular crowding of FLARE can improve the enzymatic resistance, thermostability, photostability, and binding affinity of fluorogenic RNA aptamers. Moreover, the FLARE systems can be modularly engineered into sensors (FLARES), which demonstrate enhanced brightness and sensitivity compared to free sensors dispersed in homogeneous solution. This scalable design principle provides new insights into RNA aptamer property regulation and cellular imaging.


Assuntos
Aptâmeros de Nucleotídeos , RNA , RNA/química , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Fluorescência
15.
Am J Physiol Renal Physiol ; 327(1): F158-F170, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38779755

RESUMO

Diabetes is closely associated with K+ disturbances during disease progression and treatment. However, it remains unclear whether K+ imbalance occurs in diabetes with normal kidney function. In this study, we examined the effects of dietary K+ intake on systemic K+ balance and renal K+ handling in streptozotocin (STZ)-induced diabetic mice. The control and STZ mice were fed low or high K+ diet for 7 days to investigate the role of dietary K+ intake in renal K+ excretion and K+ homeostasis and to explore the underlying mechanism by evaluating K+ secretion-related transport proteins in distal nephrons. K+-deficient diet caused excessive urinary K+ loss, decreased daily K+ balance, and led to severe hypokalemia in STZ mice compared with control mice. In contrast, STZ mice showed an increased daily K+ balance and elevated plasma K+ level under K+-loading conditions. Dysregulation of the NaCl cotransporter (NCC), epithelial Na+ channel (ENaC), and renal outer medullary K+ channel (ROMK) was observed in diabetic mice fed either low or high K+ diet. Moreover, amiloride treatment reduced urinary K+ excretion and corrected hypokalemia in K+-restricted STZ mice. On the other hand, inhibition of SGLT2 by dapagliflozin promoted urinary K+ excretion and normalized plasma K+ levels in K+-supplemented STZ mice, at least partly by increasing ENaC activity. We conclude that STZ mice exhibited abnormal K+ balance and impaired renal K+ handling under either low or high K+ diet, which could be primarily attributed to the dysfunction of ENaC-dependent renal K+ excretion pathway, despite the possible role of NCC.NEW & NOTEWORTHY Neither low dietary K+ intake nor high dietary K+ intake effectively modulates renal K+ excretion and K+ homeostasis in STZ mice, which is closely related to the abnormality of ENaC expression and activity. SGLT2 inhibitor increases urinary K+ excretion and reduces plasma K+ level in STZ mice under high dietary K+ intake, an effect that may be partly due to the upregulation of ENaC activity.


Assuntos
Diabetes Mellitus Experimental , Canais Epiteliais de Sódio , Potássio na Dieta , Potássio , Animais , Diabetes Mellitus Experimental/metabolismo , Potássio/metabolismo , Potássio/urina , Masculino , Potássio na Dieta/metabolismo , Canais Epiteliais de Sódio/metabolismo , Camundongos Endogâmicos C57BL , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Camundongos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/fisiopatologia , Rim/metabolismo , Rim/efeitos dos fármacos , Rim/fisiopatologia , Hipopotassemia/metabolismo , Amilorida/farmacologia , Eliminação Renal/efeitos dos fármacos , Homeostase , Membro 3 da Família 12 de Carreador de Soluto/metabolismo , Membro 3 da Família 12 de Carreador de Soluto/genética , Glucosídeos/farmacologia , Estreptozocina , Compostos Benzidrílicos , Transportador 2 de Glucose-Sódio
16.
Gastroenterology ; 164(6): 990-1005, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36764493

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide, but there is a deficiency of early diagnosis biomarkers and therapeutic targets. Drug resistance accounts for most HCC-related deaths, yet the mechanisms underlying drug resistance remain poorly understood. METHODS: Expression of Frizzled-10 (FZD10) in liver cancer stem cells (CSCs) was identified by means of RNA sequencing and validated by means of real-time polymerase chain reaction and immunohistochemistry. In vitro and in vivo experiments were used to assess the effect of FZD10 on liver CSC expansion and lenvatinib resistance. RNA sequencing, RNA binding protein immunoprecipitation, and luciferase report assays were applied to explore the mechanism underlying FZD10-mediated liver CSCs expansion and lenvatinib resistance. RESULTS: Activation of FZD10 in liver CSCs was mediated by METTL3-dependent N6-methyladenosine methylation of FZD10 messenger RNA. Functional studies revealed that FZD10 promotes self-renewal, tumorigenicity, and metastasis of liver CSCs via activating ß-catenin and YAP1. The FZD10-ß-catenin/YAP1 axis is activated in liver CSCs and predicts poor prognosis. Moreover, FZD10-ß-catenin/c-Jun axis transcriptionally activates METTL3 expression, forming a positive feedback loop. Importantly, the FZD10/ß-catenin/c-Jun/MEK/ERK axis determines the responses of hepatoma cells to lenvatinib treatment. Analysis of patient cohort, patient-derived tumor organoids, and patient-derived xenografts further suggest that FZD10 might predict lenvatinib clinical benefit in patients with HCC. Furthermore, treatment of lenvatinib-resistant HCC with adeno-associated virus targeting FZD10 or a ß-catenin inhibitor restored lenvatinib response. CONCLUSIONS: Elevated FZD10 expression promotes expansion of liver CSCs and lenvatinib resistance, indicating that FZD10 expression is a novel prognostic biomarker and therapeutic target for human HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Receptores Frizzled/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Via de Sinalização Hippo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Metiltransferases/genética , Células-Tronco Neoplásicas/patologia , Regulação para Cima , Via de Sinalização Wnt
17.
Anal Chem ; 96(10): 4299-4307, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38414258

RESUMO

To boost the enzyme-like activity, biological compatibility, and antiaggregation effect of noble-metal-based nanozymes, folic-acid-strengthened Ag-Ir quantum dots (FA@Ag-Ir QDs) were developed. Not only did FA@Ag-Ir QDs exhibit excellent synergistic-enhancement peroxidase-like activity, high stability, and low toxicity, but they could also promote the lateral root propagation of Arabidopsis thaliana. Especially, ultratrace cysteine or Hg2+ could exclusively strengthen or deteriorate the inherent fluorescence property with an obvious "turn-on" or "turn-off" effect, and dopamine could alter the peroxidase-like activity with a clear hypochromic effect from blue to colorless. Under optimized conditions, FA@Ag-Ir QDs were successfully applied for the turn-on fluorescence imaging of cysteine or the stress response in cells and plant roots, the turn-off fluorescence monitoring of toxic Hg2+, or the visual detection of dopamine in aqueous, beverage, serum, or medical samples with low detection limits and satisfactory recoveries. The selective recognition mechanisms for FA@Ag-Ir QDs toward cysteine, Hg2+, and dopamine were illustrated. This work will offer insights into constructing some efficient nanozyme sensors for multichannel environmental analyses, especially for the prediagnosis of cysteine-related diseases or stress responses in organisms.


Assuntos
Mercúrio , Pontos Quânticos , Pontos Quânticos/toxicidade , Cisteína , Dopamina , Ácido Fólico , Imagem Óptica , Peroxidases , Raízes de Plantas
18.
Biochem Biophys Res Commun ; 690: 149252, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995452

RESUMO

Alfalfa (Medicago sativa L.), a crucial and widely grown forage legume, faces yield and quality challenges due to salinity stress. The defender against apoptotic death (DAD) gene, recognized initially as an apoptosis suppressor in mammals, plays a pivotal role in catalyzing N-glycosylation, acting as a positive regulator for protein folding and endoplasmic reticulum (ER) export. Here, we found that the MsDAD2 gene was specially induced in the salt-tolerant alfalfa cultivar (DL) under salinity stress, but not in the salt-sensitive cultivar (SD). Overexpression of MsDAD2 enhanced the salinity resistance of transgenic alfalfa by promoting NAD(P)H-quinone oxidoreductase (NQO1) and cytochrome b6f complex subunit (Cyt b6/f) expression, thereby mitigating reactive oxygen species (ROS) production. ChIP-qPCR analysis suggested that the differential expression of MsDAD2 in DL and SD under salinity stress may be linked to dynamic histone modifications in its promoter. Therefore, our findings elucidate a novel regulatory mechanism of MsDAD2 in alfalfa's response to salinity stress, underscoring its significance as a target for alfalfa breeding to enhance salt tolerance.


Assuntos
Regulação da Expressão Gênica de Plantas , Medicago sativa , Medicago sativa/genética , Medicago sativa/metabolismo , Estresse Salino/genética , Tolerância ao Sal/genética , Salinidade
19.
Development ; 148(7)2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33688074

RESUMO

Discs large (Dlg) is an essential polarity protein and a tumor suppressor originally characterized in Drosophila but also well conserved in vertebrates. Like the majority of polarity proteins, plasma membrane (PM)/cortical localization of Dlg is required for its function in polarity and tumorigenesis, but the exact mechanisms targeting Dlg to the PM remain to be fully elucidated. Here, we show that, similar to recently discovered polybasic polarity proteins such as Lgl and aPKC, Dlg also contains a positively charged polybasic domain that electrostatically binds the PM phosphoinositides PI4P and PI(4,5)P2 Electrostatic targeting by the polybasic domain contributes significantly to the PM localization of Dlg in follicular and early embryonic epithelial cells, and is crucial for Dlg to regulate both polarity and tumorigenesis. The electrostatic PM targeting of Dlg is controlled by a potential phosphorylation-dependent allosteric regulation of its polybasic domain, and is specifically enhanced by the interactions between Dlg and another basolateral polarity protein and tumor suppressor, Scrib. Our studies highlight an increasingly significant role of electrostatic PM targeting of polarity proteins in regulating cell polarity.


Assuntos
Membrana Celular/metabolismo , Proteínas de Drosophila/metabolismo , Eletricidade Estática , Proteínas Supressoras de Tumor/metabolismo , Animais , Animais Geneticamente Modificados , Carcinogênese/metabolismo , Membrana Celular/genética , Fenômenos Fisiológicos Celulares , Polaridade Celular , Drosophila/metabolismo , Proteínas de Drosophila/genética , Células Epiteliais/metabolismo , Feminino , Genes Supressores de Tumor , Masculino , Proteínas Supressoras de Tumor/genética
20.
Small ; 20(29): e2311461, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38386310

RESUMO

PbS quantum dot (QD) solar cells harvest near-infrared solar radiation. Their conventional hole transport layer has limited hole collection efficiency due to energy level mismatch and poor film quality. Here, how to resolve these two issues by using Ag-doped PbS QDs are demonstrated. On the one hand, Ag doping relieves the compressive stress during layer deposition and thus improves film compactness and homogeneity to suppress leakage currents. On the other hand, Ag doping increases hole concentration, which aligns energy levels and increases hole mobility to boost hole collection. Increased hole concentration also broadens the depletion region of the active layer, decreasing interface charge accumulation and promoting carrier extraction efficiency. A champion power conversion efficiency of 12.42% is achieved by optimizing the hole transport layer in PbS QD solar cells, compared to 9.38% for control devices. Doping can be combined with compressive strain relief to optimize carrier concentration and energy levels in QDs, and even introduce other novel phenomena such as improved film quality.

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