Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 111
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Am Chem Soc ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597345

RESUMO

Deubiquitinase-targeting chimeras (DUBTACs) have been recently developed to stabilize proteins of interest, which is in contrast to targeted protein degradation (TPD) approaches that degrade disease-causing proteins. However, to date, only the OTUB1 deubiquitinase has been utilized to develop DUBTACs via an OTUB1 covalent ligand, which could unexpectedly compromise the endogenous function of OTUB1 owing to its covalent nature. Here, we show for the first time that deubiquitinase USP7 can be harnessed for DUBTAC development. Based on a noncovalent ligand of USP7, we developed USP7-based DUBTACs that stabilized the ΔF508-CFTR mutant protein as effectively as the previously reported OTUB1-based DUBTAC. Importantly, using two different noncovalent ligands of USP7, we developed the first AMPK DUBTACs that appear to selectively stabilize different isoforms of AMPKß, leading to elevated AMPK signaling. Overall, these results highlight that, in addition to OTUB1, USP7 can be leveraged to develop DUBTACs, thus significantly expanding the limited toolbox for targeted protein stabilization and the development of novel AMPK DUBTACs as potential therapeutics.

2.
bioRxiv ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38617310

RESUMO

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. The primary causes of COPD are environmental, including cigarette smoking; however, genetic susceptibility also contributes to COPD risk. Genome-Wide Association Studies (GWASes) have revealed more than 80 genetic loci associated with COPD, leading to the identification of multiple COPD GWAS genes. However, the biological relationships between the identified COPD susceptibility genes are largely unknown. Genes associated with a complex disease are often in close network proximity, i.e. their protein products often interact directly with each other and/or similar proteins. In this study, we use affinity purification mass spectrometry (AP-MS) to identify protein interactions with HHIP , a well-established COPD GWAS gene which is part of the sonic hedgehog pathway, in two disease-relevant lung cell lines (IMR90 and 16HBE). To better understand the network neighborhood of HHIP , its proximity to the protein products of other COPD GWAS genes, and its functional role in COPD pathogenesis, we create HUBRIS, a protein-protein interaction network compiled from 8 publicly available databases. We identified both common and cell type-specific protein-protein interactors of HHIP. We find that our newly identified interactions shorten the network distance between HHIP and the protein products of several COPD GWAS genes, including DSP, MFAP2, TET2 , and FBLN5 . These new shorter paths include proteins that are encoded by genes involved in extracellular matrix and tissue organization. We found and validated interactions to proteins that provide new insights into COPD pathobiology, including CAVIN1 (IMR90) and TP53 (16HBE). The newly discovered HHIP interactions with CAVIN1 and TP53 implicate HHIP in response to oxidative stress.

3.
J Am Chem Soc ; 146(11): 7584-7593, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38469801

RESUMO

Given the prevalent advancements in DNA- and RNA-based PROTACs, there remains a significant need for the exploration and expansion of more specific DNA-based tools, thus broadening the scope and repertoire of DNA-based PROTACs. Unlike conventional A- or B-form DNA, Z-form DNA is a configuration that exclusively manifests itself under specific stress conditions and with specific target sequences, which can be recognized by specific reader proteins, such as ADAR1 or ZBP1, to exert downstream biological functions. The core of our innovation lies in the strategic engagement of Z-form DNA with ADAR1 and its degradation is achieved by leveraging a VHL ligand conjugated to Z-form DNA to recruit the E3 ligase. This ingenious construct engendered a series of Z-PROTACs, which we utilized to selectively degrade the Z-DNA-binding protein ADAR1, a molecule that is frequently overexpressed in cancer cells. This meticulously orchestrated approach triggers a cascade of PANoptotic events, notably encompassing apoptosis and necroptosis, by mitigating the blocking effect of ADAR1 on ZBP1, particularly in cancer cells compared with normal cells. Moreover, the Z-PROTAC design exhibits a pronounced predilection for ADAR1, as opposed to other Z-DNA readers, such as ZBP1. As such, Z-PROTAC likely elicits a positive immunological response, subsequently leading to a synergistic augmentation of cancer cell death. In summary, the Z-DNA-based PROTAC (Z-PROTAC) approach introduces a modality generated by the conformational change from B- to Z-form DNA, which harnesses the structural specificity intrinsic to potentiate a selective degradation strategy. This methodology is an inspiring conduit for the advancement of PROTAC-based therapeutic modalities, underscoring its potential for selectivity within the therapeutic landscape of PROTACs to target undruggable proteins.


Assuntos
DNA Forma Z , Quimera de Direcionamento de Proteólise , Proteólise , Adenosina Desaminase/metabolismo , RNA/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Ligação a DNA/metabolismo
4.
EBioMedicine ; 101: 105026, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417378

RESUMO

BACKGROUND: An intergenic region at chromosome 4q31 is one of the most significant regions associated with COPD susceptibility and lung function in GWAS. In this region, the implicated causal gene HHIP has a unique epithelial expression pattern in adult human lungs, in contrast to dominant expression in fibroblasts in murine lungs. However, the mechanism underlying the species-dependent cell type-specific regulation of HHIP remains largely unknown. METHODS: We employed snATAC-seq analysis to identify open chromatin regions within the COPD GWAS region in various human lung cell types. ChIP-quantitative PCR, reporter assays, chromatin conformation capture assays and Hi-C assays were conducted to characterize the regulatory element in this region. CRISPR/Cas9-editing was performed in BEAS-2B cells to generate single colonies with stable knockout of the regulatory element. RT-PCR and Western blot assays were used to evaluate expression of HHIP and epithelial-mesenchymal transition (EMT)-related marker genes. FINDINGS: We identified a distal enhancer within the COPD 4q31 GWAS locus that regulates HHIP transcription at baseline and after TGFß treatment in a SMAD3-dependent, but Hedgehog-independent manner in human bronchial epithelial cells. The distal enhancer also maintains chromatin topological domains near 4q31 locus and HHIP gene. Reduced HHIP expression led to increased EMT induced by TGFß in human bronchial epithelial cells. INTERPRETATION: A distal enhancer regulates HHIP expression both under homeostatic condition and upon TGFß treatment in human bronchial epithelial cells. The interaction between HHIP and TGFß signalling possibly contributes to COPD pathogenesis. FUNDING: Supported by NIH grants R01HL127200, R01HL148667 and R01HL162783 (to X. Z).


Assuntos
Proteínas Hedgehog , Doença Pulmonar Obstrutiva Crônica , Adulto , Humanos , Animais , Camundongos , Proteínas Hedgehog/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Pulmão/patologia , Células Epiteliais/metabolismo , Cromatina/genética , Cromatina/metabolismo , Fator de Crescimento Transformador beta/metabolismo
5.
Sci Transl Med ; 15(725): eadh7668, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38055802

RESUMO

Targeting angiotensin-converting enzyme 2 (ACE2) represents a promising and effective approach to combat not only the COVID-19 pandemic but also potential future pandemics arising from coronaviruses that depend on ACE2 for infection. Here, we report ubiquitin specific peptidase 2 (USP2) as a host-directed antiviral target; we further describe the development of MS102, an orally available USP2 inhibitor with viable antiviral activity against ACE2-dependent coronaviruses. Mechanistically, USP2 serves as a physiological deubiquitinase of ACE2, and targeted inhibition with specific small-molecule inhibitor ML364 leads to a marked and reversible reduction in ACE2 protein abundance, thereby blocking various ACE2-dependent coronaviruses tested. Using human ACE2 transgenic mouse models, we further demonstrate that ML364 efficiently controls disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as evidenced by reduced viral loads and ameliorated lung inflammation. Furthermore, we improved the in vivo performance of ML364 in terms of both pharmacokinetics and antiviral activity. The resulting lead compound, MS102, holds promise as an oral therapeutic option for treating infections with coronaviruses that are reliant on ACE2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2 , Antivirais/farmacologia , Antivirais/uso terapêutico , Camundongos Transgênicos , Pandemias , Peptidil Dipeptidase A/metabolismo , Ubiquitina Tiolesterase
6.
Cell Metab ; 35(12): 2183-2199.e7, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38006878

RESUMO

Methionine is an essential branch of diverse nutrient inputs that dictate mTORC1 activation. In the absence of methionine, SAMTOR binds to GATOR1 and inhibits mTORC1 signaling. However, how mTORC1 is activated upon methionine stimulation remains largely elusive. Here, we report that PRMT1 senses methionine/SAM by utilizing SAM as a cofactor for an enzymatic activity-based regulation of mTORC1 signaling. Under methionine-sufficient conditions, elevated cytosolic SAM releases SAMTOR from GATOR1, which confers the association of PRMT1 with GATOR1. Subsequently, SAM-loaded PRMT1 methylates NPRL2, the catalytic subunit of GATOR1, thereby suppressing its GAP activity and leading to mTORC1 activation. Notably, genetic or pharmacological inhibition of PRMT1 impedes hepatic methionine sensing by mTORC1 and improves insulin sensitivity in aged mice, establishing the role of PRMT1-mediated methionine sensing at physiological levels. Thus, PRMT1 coordinates with SAMTOR to form the methionine-sensing apparatus of mTORC1 signaling.


Assuntos
Metionina , Transdução de Sinais , Animais , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Metionina/metabolismo , Racemetionina/metabolismo , Metilação
7.
J Am Chem Soc ; 145(40): 21871-21878, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37774414

RESUMO

Methyl-CpG-binding protein 2 (MeCP2), a reader of DNA methylation, has been extensively investigated for its function in neurological and neurodevelopmental disorders. Emerging evidence indicates that MeCP2 exerts an oncogenic function in cancer; however, the endeavor to develop a MeCP2-targeted therapy remains a challenge. This work attempts to address it by introducing a methylated nucleotide-based targeting chimera termed methyl-proteolysis-targeting chimera (methyl-PROTAC). The methyl-PROTAC incorporates a methylated cytosine into an oligodeoxynucleotide moiety to recruit MeCP2 for targeted degradation in a von Hippel-Lindau- and proteasome-dependent manner, thus displaying antiproliferative effects in cancer cells reliant on MeCP2 overexpression. This selective cytotoxicity endows methyl-PROTAC with the capacity to selectively eliminate cancer cells that are addicted to the overexpression of the MeCP2 oncoprotein. Furthermore, methyl-PROTAC-mediated MeCP2 degradation induces apoptosis in cancer cells. These findings underscore the therapeutic potential of methyl-PROTAC to degrade undruggable epigenetic regulatory proteins. In summary, the development of methyl-PROTAC introduces an innovative strategy by designing a modified nucleotide-based degradation approach for manipulating epigenetic factors, thereby representing a promising avenue for the advancement of PROTAC-based therapeutics.


Assuntos
Proteína 2 de Ligação a Metil-CpG , Nucleotídeos , Proteína 2 de Ligação a Metil-CpG/genética , Nucleotídeos/metabolismo , Proteólise , Fatores de Transcrição/metabolismo , Metilação de DNA
8.
Nat Cell Biol ; 25(7): 950-962, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37400498

RESUMO

The prolyl hydroxylation of hypoxia-inducible factor 1α (HIF-1α) mediated by the EGLN-pVHL pathway represents a classic signalling mechanism that mediates cellular adaptation under hypoxia. Here we identify RIPK1, a known regulator of cell death mediated by tumour necrosis factor receptor 1 (TNFR1), as a target of EGLN1-pVHL. Prolyl hydroxylation of RIPK1 mediated by EGLN1 promotes the binding of RIPK1 with pVHL to suppress its activation under normoxic conditions. Prolonged hypoxia promotes the activation of RIPK1 kinase by modulating its proline hydroxylation, independent of the TNFα-TNFR1 pathway. As such, inhibiting proline hydroxylation of RIPK1 promotes RIPK1 activation to trigger cell death and inflammation. Hepatocyte-specific Vhl deficiency promoted RIPK1-dependent apoptosis to mediate liver pathology. Our findings illustrate a key role of the EGLN-pVHL pathway in suppressing RIPK1 activation under normoxic conditions to promote cell survival and a model by which hypoxia promotes RIPK1 activation through modulating its proline hydroxylation to mediate cell death and inflammation in human diseases, independent of TNFR1.


Assuntos
Necroptose , Receptores Tipo I de Fatores de Necrose Tumoral , Humanos , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Hidroxilação , Hipóxia , Prolina/metabolismo , Inflamação , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
9.
Neoplasia ; 42: 100912, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37269817

RESUMO

N6-methyladenosine (m6A), the most abundant mRNA modification in mammalian cells, is responsible for mRNA stability and alternative splicing. The METTL3-METTL14-WTAP complex is the only methyltransferase for the m6A modification. Thus, regulation of its enzymatic activity is critical for the homeostasis of mRNA m6A levels in cells. However, relatively little is known about the upstream regulation of the METTL3-METTL14-WTAP complex, especially at the post-translational modification level. The C-terminal RGG repeats of METTL14 are critical for RNA binding. Therefore, modifications on these residues may play a regulatory role in its function. Arginine methylation is a post-translational modification catalyzed by protein arginine methyltransferases (PRMTs), among which PRMT1 preferentially methylates protein substrates with an arginine/glycine-rich motif. In addition, PRMT1 functions as a key regulator of mRNA alternative splicing, which is associated with m6A modification. To this end, we report that PRMT1 promotes the asymmetric methylation of two major arginine residues at the C-terminus of METTL14, and the reader protein SPF30 recognizes this modification. Functionally, PRMT1-mediated arginine methylation on METTL14 is likely essential for its function in catalyzing the m6A modification. Moreover, arginine methylation of METTL14 promotes cell proliferation that is antagonized by the PRMT1 inhibitor MS023. These results indicate that PRMT1 likely regulates m6A modification and promotes tumorigenesis through arginine methylation at the C-terminus of METTL14.


Assuntos
Arginina , Metiltransferases , Animais , Humanos , Metiltransferases/genética , Metiltransferases/metabolismo , Metilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Arginina/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismo
10.
Science ; 380(6652): 1372-1380, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37384704

RESUMO

Adenosine monophosphate-activated protein kinase (AMPK) activity is stimulated to promote metabolic adaptation upon energy stress. However, sustained metabolic stress may cause cell death. The mechanisms by which AMPK dictates cell death are not fully understood. We report that metabolic stress promoted receptor-interacting protein kinase 1 (RIPK1) activation mediated by TRAIL receptors, whereas AMPK inhibited RIPK1 by phosphorylation at Ser415 to suppress energy stress-induced cell death. Inhibiting pS415-RIPK1 by Ampk deficiency or RIPK1 S415A mutation promoted RIPK1 activation. Furthermore, genetic inactivation of RIPK1 protected against ischemic injury in myeloid Ampkα1-deficient mice. Our studies reveal that AMPK phosphorylation of RIPK1 represents a crucial metabolic checkpoint, which dictates cell fate response to metabolic stress, and highlight a previously unappreciated role for the AMPK-RIPK1 axis in integrating metabolism, cell death, and inflammation.


Assuntos
Proteínas Quinases Ativadas por AMP , Metabolismo Energético , Necroptose , Proteína Serina-Treonina Quinases de Interação com Receptores , Estresse Fisiológico , Animais , Camundongos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Fosforilação , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Inflamação/metabolismo , Isquemia/metabolismo
11.
Adv Protein Chem Struct Biol ; 135: 179-201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37061331

RESUMO

The recent findings advance our knowledge for the prevention of the premature activation of the major oncogenic pathways including MYC and the cyclin D-cyclin-dependent kinases 4 and 6 (CDK4/6) axis. D-type cyclins are frequently deregulated in human cancer and promote cell division in part through activation of CDK4/6. Therefore, the activation of the cyclin D-CDK4/6 axis stimulates cell proliferation and cancer progression, which represents a unique therapeutic target. However, we have shown that inhibition of CDK4/6 upregulates protein levels of RB1 and CDK6 for acquisition of drug resistance to CDK4/6 inhibitors. Here, we review new progress in the control of cyclin D-dependent cancer cell cycle and proliferation, along with identification of novel E3 ligase for the stability of cyclin D. Cullin4-RING E3 ligase (CRL4)AMBRA1 complex plays a critical role in regulating D-type cyclins through their protein destabilization to control S phase entry and maintain genomic integrity. We also summarize the strategy for inhibition of the cyclin D-associated kinases CDK4/6 and other potential cell cycle regulators for targeting cancer with altered cyclin D expression. We also uncover the function of CK1ɛ as an effective target to potentiate therapeutic efficacy of CDK4/6 inhibitors. Moreover, as the level of PD-L1 is considered in the severe clinical problem in the patients treated with CDK4 inhibitors, we assume that a therapeutic combination using PD-L1 immunotherapy might lower the development of drug resistance and targeting cyclin D will likely inhibit tumor growth and overcome resistance to cyclin D-associated CDK4/6 inhibitors.


Assuntos
Antígeno B7-H1 , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Proteína do Retinoblastoma/metabolismo , Fosforilação , Ciclinas/genética , Ciclina D/metabolismo , Transdução de Sinais , Neoplasias/tratamento farmacológico , Carcinogênese , Quinase 4 Dependente de Ciclina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
12.
J Biol Chem ; 299(4): 104572, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870680

RESUMO

Post-translational modifications (PTMs) regulate all aspects of protein function. Therefore, upstream regulators of PTMs, such as kinases, acetyltransferases, or methyltransferases, are potential therapeutic targets for human diseases, including cancer. To date, multiple inhibitors and/or agonists of these PTM upstream regulators are in clinical use, while others are still in development. However, these upstream regulators control not only the PTMs of disease-related target proteins but also other disease-irrelevant substrate proteins. Thus, nontargeted perturbing activities may introduce unwanted off-target toxicity issues that limit the use of these drugs in successful clinical applications. Therefore, alternative drugs that solely regulate a specific PTM of the disease-relevant protein target may provide a more precise effect in treating disease with relatively low side effects. To this end, chemically induced proximity has recently emerged as a powerful research tool, and several chemical inducers of proximity (CIPs) have been used to target and regulate protein ubiquitination, phosphorylation, acetylation, and glycosylation. These CIPs have a high potential to be translated into clinical drugs and several examples such as PROTACs and MGDs are now in clinical trials. Hence, more CIPs need to be developed to cover all types of PTMs, such as methylation and palmitoylation, thus providing a full spectrum of tools to regulate protein PTM in basic research and also in clinical application for effective cancer treatment.


Assuntos
Neoplasias , Processamento de Proteína Pós-Traducional , Humanos , Proteínas , Ubiquitinação , Fosforilação , Glicosilação , Acetilação , Neoplasias/tratamento farmacológico
13.
Neoplasia ; 38: 100890, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871351

RESUMO

SKP2, an F-box protein of the SCF type of the E3 ubiquitin ligase complex, plays an important function in driving tumorigenesis through the destruction of numerous tumor-suppressive proteins. Besides its critical role in cell cycle regulation, proto-oncogenic functions of SKP2 have also been shown in a cell cycle regulation-independent manner. Therefore, uncovering novel physiological upstream regulators of SKP2 signaling pathways would be essential to retard aggressive malignancies. Here, we report that elevation of SKP2 and EP300 transcriptomic expression is a hallmark of castration-resistant prostate cancer. We also found that SKP2 acetylation is likely a critical driven event in castration-resistant prostate cancer cells. Mechanistically, SKP2-acetylation is mediated by the p300 acetyltransferase enzyme for post-translational modification (PTM) event that is induced upon stimulation with dihydrotestosterone (DHT) in prostate cancer cells. Moreover, ectopic expression of acetylation-mimetic K68/71Q mutant of SKP2 in LNCaP cells could confer resistance to androgen withdrawal-induced growth arrest and promotes prostate cancer stem cell (CSC)-like traits including survival, proliferation, stemness formation, lactate production, migration, and invasion. Furthermore, inhibition of p300-mediated SKP2 acetylation or SKP2-mediated p27-degradation by pharmacological inhibition of p300 or SKP2 could attenuate epithelial-mesenchymal transition (EMT) and the proto-oncogenic activities of the SKP2/p300 and androgen receptor (AR) signaling pathways. Therefore, our study identifies the SKP2/p300 axis as a possible molecular mechanism driving castration-resistant prostate cancers, which provides pharmaceutical insight into inactivation of the SKP2/p300 axis for restriction of CSC-like properties, thereby benefiting clinical diagnosis and cancer therapy.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/metabolismo , Androgênios , Transdução de Sinais , Processamento de Proteína Pós-Traducional , Linhagem Celular Tumoral
14.
Nat Metab ; 5(2): 265-276, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732624

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth in response to amino acid and glucose levels. However, how mTORC1 senses glucose availability to regulate various downstream signalling pathways remains largely elusive. Here we report that AMP-activated protein kinase (AMPK)-mediated phosphorylation of WDR24, a core component of the GATOR2 complex, has a role in the glucose-sensing capability of mTORC1. Mechanistically, glucose deprivation activates AMPK, which directly phosphorylates WDR24 on S155, subsequently disrupting the integrity of the GATOR2 complex to suppress mTORC1 activation. Phosphomimetic Wdr24S155D knock-in mice exhibit early embryonic lethality and reduced mTORC1 activity. On the other hand, compared to wild-type littermates, phospho-deficient Wdr24S155A knock-in mice are more resistant to fasting and display elevated mTORC1 activity. Our findings reveal that AMPK-mediated phosphorylation of WDR24 modulates glucose-induced mTORC1 activation, thereby providing a rationale for targeting AMPK-WDR24 signalling to fine-tune mTORC1 activation as a potential therapeutic means to combat human diseases with aberrant activation of mTORC1 signalling including cancer.


Assuntos
Proteínas Quinases Ativadas por AMP , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos , Serina-Treonina Quinases TOR , Animais , Humanos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Complexos Multiproteicos/metabolismo , Fosforilação , Serina-Treonina Quinases TOR/metabolismo
15.
Mol Cell ; 83(1): 74-89.e9, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36528027

RESUMO

The GATOR2-GATOR1 signaling axis is essential for amino-acid-dependent mTORC1 activation. However, the molecular function of the GATOR2 complex remains unknown. Here, we report that disruption of the Ring domains of Mios, WDR24, or WDR59 completely impedes amino-acid-mediated mTORC1 activation. Mechanistically, via interacting with Ring domains of WDR59 and WDR24, the Ring domain of Mios acts as a hub to maintain GATOR2 integrity, disruption of which leads to self-ubiquitination of WDR24. Physiologically, leucine stimulation dissociates Sestrin2 from the Ring domain of WDR24 and confers its availability to UBE2D3 and subsequent ubiquitination of NPRL2, contributing to GATOR2-mediated GATOR1 inactivation. As such, WDR24 ablation or Ring deletion prevents mTORC1 activation, leading to severe growth defects and embryonic lethality at E10.5 in mice. Hence, our findings demonstrate that Ring domains are essential for GATOR2 to transmit amino acid availability to mTORC1 and further reveal the essentiality of nutrient sensing during embryonic development.


Assuntos
Complexos Multiproteicos , Serina-Treonina Quinases TOR , Animais , Camundongos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais
16.
Nature ; 609(7927): 502-506, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36104553

RESUMO

Hund's multiplicity rule states that a higher spin state has a lower energy for a given electronic configuration1. Rephrasing this rule for molecular excited states predicts a positive energy gap between spin-singlet and spin-triplet excited states, as has been consistent with numerous experimental observations over almost a century. Here we report a fluorescent molecule that disobeys Hund's rule and has a negative singlet-triplet energy gap of -11 ± 2 meV. The energy inversion of the singlet and triplet excited states results in delayed fluorescence with short time constants of 0.2 µs, which anomalously decrease with decreasing temperature owing to the emissive singlet character of the lowest-energy excited state. Organic light-emitting diodes (OLEDs) using this molecule exhibited a fast transient electroluminescence decay with a peak external quantum efficiency of 17%, demonstrating its potential implications for optoelectronic devices, including displays, lighting and lasers.

17.
Semin Cancer Biol ; 86(Pt 3): 32-40, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35908574

RESUMO

Necroptosis is a caspase-independent form of programmed cell death executed by the receptor interacting protein kinase 1 (RIPK1)-RIPK3-mixed lineage kinase domain-like protein (MLKL) signaling cascade, deregulation of which can cause various human diseases including cancer. Escape from programmed cell death is a hallmark of cancer, leading to uncontrolled growth and drug resistance. Therefore, it is crucial to further understand whether necroptosis plays a key role in therapeutic resistance. In this review, we summarize the recent findings of the link between necroptosis and cancer, and discuss that targeting necroptosis is a new strategy to overcome apoptosis resistance in tumor therapy.


Assuntos
Necroptose , Proteínas Quinases , Humanos , Necroptose/genética , Apoptose/genética , Transdução de Sinais , Carcinogênese/genética
18.
Semin Cancer Biol ; 86(Pt 2): 269-279, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35798235

RESUMO

Tumor microenvironment (TME) composes of multiple cell types and non-cellular components, which supports the proliferation, metastasis and immune surveillance evasion of tumor cells, as well as accounts for the resistance to therapies. Therefore, therapeutic strategies using small molecule inhibitors (SMIs) and antibodies to block potential targets in TME are practical for cancer treatment. Targeted protein degradation using PROteolysis-TArgeting Chimera (PROTAC) technic has several advantages over traditional SMIs and antibodies, including overcoming drug resistance. Thus many PROTACs are currently under development for cancer treatment. In this review, we summarize the recent progress of PROTAC development that target TME pathways and propose the potential direction of future PROTAC technique to advance as novel cancer treatment options.


Assuntos
Descoberta de Drogas , Neoplasias , Humanos , Descoberta de Drogas/métodos , Proteólise , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Ubiquitina-Proteína Ligases/metabolismo , Microambiente Tumoral
19.
J Am Chem Soc ; 144(16): 7302-7307, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35414173

RESUMO

Chirality-induced current-perpendicular-to-plane magnetoresistance (CPP-MR) originates from current-induced spin polarization in molecules. The current-induced spin polarization is widely recognized as a fundamental principle of chiral-induced spin selectivity (CISS). In this study, we investigate chirality-induced current-in-plane magnetoresistance (CIP-MR) in a chiral molecule/ferromagnetic metal bilayer at room temperature. In contrast to CPP-MR, CIP-MR observed in the present study requires no bias charge current through the molecule. The temperature dependence of CIP-MR suggests that thermally driven spontaneous spin polarization in chiral molecules is the key to the observed MR. The novel MR is consistent with recent CISS-related studies, that is, chiral molecules in contact with a metallic surface possess a finite spin polarization.

20.
Acta Mater Med ; 1(1): 24-41, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237768

RESUMO

Neurodegenerative diseases (NDs) are characteristic with progression of neuron degeneration, resulting in dysfunction of cognition and mobility. Many neurodegenerative diseases are because of proteinopathies that results from unusual protein accumulations and aggregations. The aggregation of misfolded proteins like ß-amyloid, α-synuclein, tau, and polyglutamates are hallmarked in Alzheimer's disease (AD), which are undruggable targets, and usually do not respond to conventional small-molecule agents. Therefore, developing novel technology and strategy for reducing the levels of protein aggregates would be critical for treatment of AD. Recently, the emerging proteolysis targeting chimeras (PRPTACs) technology has been significantly considered for artificial and selective degradation of aberrant target proteins. These engineered bifunctional molecules engage target proteins to be degraded by either the cellular degradation machinery in the ubiquitin-proteasome system (UPS) or via the autophagy-lysosome degradation pathway. Although the application of PROTACs technology is preferable than oligonucleotide and antibodies for treatment of NDs, many limitations such as their pharmacokinetic properties, tissue distribution and cell permeabilities, still need to be corrected. Herein, we review the recent advances in PROTACs technology with their limitation for pharmaceutical targeting of aberrant proteins involved in Alzheimer's diseases. We also review therapeutic potential of dysregulated signaling such as PI3K/AKT/mTOR axis for the management of AD.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...