Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.400
Filtrar
Más filtros

Intervalo de año de publicación
1.
Cell ; 185(8): 1325-1345.e22, 2022 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-35366418

RESUMEN

Protein aggregation is a hallmark of multiple human pathologies. Autophagy selectively degrades protein aggregates via aggrephagy. How selectivity is achieved has been elusive. Here, we identify the chaperonin subunit CCT2 as an autophagy receptor regulating the clearance of aggregation-prone proteins in the cell and the mouse brain. CCT2 associates with aggregation-prone proteins independent of cargo ubiquitination and interacts with autophagosome marker ATG8s through a non-classical VLIR motif. In addition, CCT2 regulates aggrephagy independently of the ubiquitin-binding receptors (P62, NBR1, and TAX1BP1) or chaperone-mediated autophagy. Unlike P62, NBR1, and TAX1BP1, which facilitate the clearance of protein condensates with liquidity, CCT2 specifically promotes the autophagic degradation of protein aggregates with little liquidity (solid aggregates). Furthermore, aggregation-prone protein accumulation induces the functional switch of CCT2 from a chaperone subunit to an autophagy receptor by promoting CCT2 monomer formation, which exposes the VLIR to ATG8s interaction and, therefore, enables the autophagic function.


Asunto(s)
Chaperonina con TCP-1 , Macroautofagia , Agregado de Proteínas , Animales , Ratones , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/fisiología , Proteínas Portadoras/metabolismo , Chaperonina con TCP-1/metabolismo , Proteína Sequestosoma-1/metabolismo
2.
Cell ; 166(1): 152-66, 2016 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-27368102

RESUMEN

Through a network of progressively maturing vesicles, the endosomal system connects the cell's interior with extracellular space. Intriguingly, this network exhibits a bilateral architecture, comprised of a relatively immobile perinuclear vesicle "cloud" and a highly dynamic peripheral contingent. How this spatiotemporal organization is achieved and what function(s) it curates is unclear. Here, we reveal the endoplasmic reticulum (ER)-located ubiquitin ligase Ring finger protein 26 (RNF26) as the global architect of the entire endosomal system, including the trans-Golgi network (TGN). To specify perinuclear vesicle coordinates, catalytically competent RNF26 recruits and ubiquitinates the scaffold p62/sequestosome 1 (p62/SQSTM1), in turn attracting ubiquitin-binding domains (UBDs) of various vesicle adaptors. Consequently, RNF26 restrains fast transport of diverse vesicles through a common molecular mechanism operating at the ER membrane, until the deubiquitinating enzyme USP15 opposes RNF26 activity to allow vesicle release into the cell's periphery. By drawing the endosomal system's architecture, RNF26 orchestrates endosomal maturation and trafficking of cargoes, including signaling receptors, in space and time.


Asunto(s)
Retículo Endoplásmico/metabolismo , Endosomas/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Neoplasias/metabolismo , Línea Celular Tumoral , Células Dendríticas/citología , Células Dendríticas/metabolismo , Humanos , Macrófagos/citología , Macrófagos/metabolismo , Proteína Sequestosoma-1/metabolismo , Vesículas Transportadoras/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo
3.
Mol Cell ; 83(6): 927-941.e8, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36898370

RESUMEN

Mitophagy is a form of selective autophagy that disposes of superfluous and potentially damage-inducing organelles in a tightly controlled manner. While the machinery involved in mitophagy induction is well known, the regulation of the components is less clear. Here, we demonstrate that TNIP1 knockout in HeLa cells accelerates mitophagy rates and that ectopic TNIP1 negatively regulates the rate of mitophagy. These functions of TNIP1 depend on an evolutionarily conserved LIR motif as well as an AHD3 domain, which are required for binding to the LC3/GABARAP family of proteins and the autophagy receptor TAX1BP1, respectively. We further show that phosphorylation appears to regulate its association with the ULK1 complex member FIP200, allowing TNIP1 to compete with autophagy receptors, which provides a molecular rationale for its inhibitory function during mitophagy. Taken together, our findings describe TNIP1 as a negative regulator of mitophagy that acts at the early steps of autophagosome biogenesis.


Asunto(s)
Proteínas Relacionadas con la Autofagia , Autofagia , Mitofagia , Humanos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia/genética , Familia de las Proteínas 8 Relacionadas con la Autofagia/metabolismo , Proteínas de Unión al ADN/metabolismo , Células HeLa , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mitofagia/genética , Proteínas de Neoplasias/metabolismo
4.
EMBO J ; 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39448883

RESUMEN

Autophagy mediates the degradation of harmful material within lysosomes. In aggrephagy, the pathway mediating the degradation of aggregated, ubiquitinated proteins, this cargo material is collected in larger condensates prior to its sequestration by autophagosomes. In this process, the autophagic cargo receptors SQSTM1/p62 and NBR1 drive cargo condensation, while TAX1BP1, which binds to NBR1, recruits the autophagy machinery to facilitate autophagosome biogenesis at the condensates. The mechanistic basis for the TAX1BP1-mediated switch from cargo collection to its sequestration is unclear. Here we show that TAX1BP1 is not a constitutive component of the condensates. Its recruitment correlates with the induction of autophagosome biogenesis. TAX1BP1 is sufficient to recruit the TBK1 kinase via the SINTBAD adapter. We define the NBR1-TAX1BP1-binding site, which is adjacent to the GABARAP/LC3 interaction site, and demonstrate that the recruitment of TAX1BP1 to cargo mimetics can be enhanced by an increased ubiquitin load. Our study suggests that autophagosome biogenesis is initiated once sufficient cargo is collected in the condensates.

5.
Mol Cell ; 74(2): 347-362.e6, 2019 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-30853401

RESUMEN

Selective autophagy recycles damaged organelles and clears intracellular pathogens to prevent their aberrant accumulation. How ULK1 kinase is targeted and activated during selective autophagic events remains to be elucidated. In this study, we used chemically inducible dimerization (CID) assays in tandem with CRISPR KO lines to systematically analyze the molecular basis of selective autophagosome biogenesis. We demonstrate that ectopic placement of NDP52 on mitochondria or peroxisomes is sufficient to initiate selective autophagy by focally localizing and activating the ULK1 complex. The capability of NDP52 to induce mitophagy is dependent on its interaction with the FIP200/ULK1 complex, which is facilitated by TBK1. Ectopically tethering ULK1 to cargo bypasses the requirement for autophagy receptors and TBK1. Focal activation of ULK1 occurs independently of AMPK and mTOR. Our findings provide a parsimonious model of selective autophagy, which highlights the coordination of ULK1 complex localization by autophagy receptors and TBK1 as principal drivers of targeted autophagosome biogenesis.


Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Autofagia/genética , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Proteínas Relacionadas con la Autofagia , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Células HeLa , Humanos , Mitocondrias/química , Mitocondrias/genética , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Peroxisomas/química , Peroxisomas/genética , Fosforilación , Proteínas Quinasas/genética , Multimerización de Proteína , Proteínas Tirosina Quinasas/química , Proteínas Tirosina Quinasas/genética , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/genética
6.
Proc Natl Acad Sci U S A ; 121(11): e2318365121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38451950

RESUMEN

To construct a stochastic version of [R. J. Barro, J. Polit. Econ. 87, 940-971 (1979)] normative model of tax rates and debt/GDP dynamics, we add risks and markets for trading them along lines suggested by [K. J. Arrow, Rev. Econ. Stud. 31, 91-96 (1964)] and [R. J. Shiller, Creating Institutions for Managing Society's Largest Economic Risks (OUP, Oxford, 1994)]. These modifications preserve Barro's prescriptions that a government should keep its debt-gross domestic product (GDP) ratio and tax rate constant over time and also prescribe that the government insure its primary surplus risk by selling or buying the same number of shares of a Shiller macro security each period.


Asunto(s)
Gobierno , Producto Interno Bruto
7.
Proc Natl Acad Sci U S A ; 121(11): e2315550121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38437556

RESUMEN

TAX1BP1, a multifunctional autophagy adaptor, plays critical roles in different autophagy processes. As an autophagy receptor, TAX1BP1 can interact with RB1CC1, NAP1, and mammalian ATG8 family proteins to drive selective autophagy for relevant substrates. However, the mechanistic bases underpinning the specific interactions of TAX1BP1 with RB1CC1 and mammalian ATG8 family proteins remain elusive. Here, we find that there are two distinct binding sites between TAX1BP1 and RB1CC1. In addition to the previously reported TAX1BP1 SKICH (skeletal muscle and kidney enriched inositol phosphatase (SKIP) carboxyl homology)/RB1CC1 coiled-coil interaction, the first coiled-coil domain of TAX1BP1 can directly bind to the extreme C-terminal coiled-coil and Claw region of RB1CC1. We determine the crystal structure of the TAX1BP1 SKICH/RB1CC1 coiled-coil complex and unravel the detailed binding mechanism of TAX1BP1 SKICH with RB1CC1. Moreover, we demonstrate that RB1CC1 and NAP1 are competitive in binding to the TAX1BP1 SKICH domain, but the presence of NAP1's FIP200-interacting region (FIR) motif can stabilize the ternary TAX1BP1/NAP1/RB1CC1 complex formation. Finally, we elucidate the molecular mechanism governing the selective interactions of TAX1BP1 with ATG8 family members by solving the structure of GABARAP in complex with the non-canonical LIR (LC3-interacting region) motif of TAX1BP1, which unveils a unique binding mode between LIR and ATG8 family protein. Collectively, our findings provide mechanistic insights into the interactions of TAX1BP1 with RB1CC1 and mammalian ATG8 family proteins and are valuable for further understanding the working mode and function of TAX1BP1 in autophagy.


Asunto(s)
Autofagia , Proteínas de Ciclo Celular , Animales , Familia de las Proteínas 8 Relacionadas con la Autofagia , Sitios de Unión , Riñón , Mamíferos
8.
Proc Natl Acad Sci U S A ; 120(31): e2216127120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487091

RESUMEN

Retroviruses and their host have coevolved in a delicate balance between viral replication and survival of the infected cell. In this equilibrium, restriction factors expressed by infected cells control different steps of retroviral replication such as entry, uncoating, nuclear import, expression, or budding. Here, we describe a mechanism of restriction against human T cell leukemia virus type 1 (HTLV-1) by the helicase-like transcription factor (HLTF). We show that RNA and protein levels of HLTF are reduced in primary T cells of HTLV-1-infected subjects, suggesting a clinical relevance. We further demonstrate that the viral oncogene Tax represses HLTF transcription via the Enhancer of zeste homolog 2 methyltransferase of the Polycomb repressive complex 2. The Tax protein also directly interacts with HLTF and induces its proteasomal degradation. RNA interference and gene transduction in HTLV-1-infected T cells derived from patients indicate that HLTF is a restriction factor. Restoring the normal levels of HLTF expression induces the dispersal of the Golgi apparatus and overproduction of secretory granules. By synergizing with Tax-mediated NF-κB activation, physiologically relevant levels of HLTF intensify the autophagic flux. Increased vesicular trafficking leads to an enlargement of the lysosomes and the production of large vacuoles containing viral particles. HLTF induction in HTLV-1-infected cells significantly increases the percentage of defective virions. In conclusion, HLTF-mediated activation of the autophagic flux blunts the infectious replication cycle of HTLV-1, revealing an original mode of viral restriction.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Leucemia de Células T , Humanos , Virus Linfotrópico T Tipo 1 Humano/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Productos del Gen tax/genética , Productos del Gen tax/metabolismo , Linfocitos T/metabolismo , FN-kappa B/metabolismo , Proteínas de Unión al ADN
9.
J Virol ; 98(7): e0040524, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38874362

RESUMEN

Human T-cell leukemia virus type 1 (HTLV-I) is the etiological agent of adult T-cell leukemia (ATL). Mutational analysis has demonstrated that the tumor suppressor, F-box and WD repeat domain containing 7 (FBXW7/FBW7/CDC4), is mutated in primary ATL patients. However, even in the absence of genetic mutations, FBXW7 substrates are stabilized in ATL cells, suggesting additional mechanisms can prevent FBXW7 functions. Here, we report that the viral oncoprotein Tax represses FBXW7 activity, resulting in the stabilization of activated Notch intracellular domain, c-MYC, Cyclin E, and myeloid cell leukemia sequence 1 (BCL2-related) (Mcl-1). Mechanistically, we demonstrate that Tax directly binds to FBXW7 in the nucleus, effectively outcompeting other targets for binding to FBXW7, resulting in decreased ubiquitination and degradation of FBXW7 substrates. In support of the nuclear role of Tax, a non-degradable form of the nuclear factor kappa B subunit 2 (NFκB2/p100) was found to delocalize Tax to the cytoplasm, thereby preventing Tax interactions with FBXW7 and Tax-mediated inhibition of FBXW7. Finally, we characterize a Tax mutant that is unable to interact with FBXW7, unable to block FBXW7 tumor suppressor functions, and unable to effectively transform fibroblasts. These results demonstrate that HTLV-I Tax can inhibit FBXW7 functions without genetic mutations to promote an oncogenic state. These results suggest that Tax-mediated inhibition of FBXW7 is likely critical during the early stages of the cellular transformation process. IMPORTANCE: F-box and WD repeat domain containing 7 (FBXW7), a critical tumor suppressor of human cancers, is frequently mutated or epigenetically suppressed. Loss of FBXW7 functions is associated with stabilization and increased expression of oncogenic factors such as Cyclin E, c-Myc, Mcl-1, mTOR, Jun, and Notch. In this study, we demonstrate that the human retrovirus human T-cell leukemia virus type 1 oncoprotein Tax directly interacts with FBXW7, effectively outcompeting other targets for binding to FBXW7, resulting in decreased ubiquitination and degradation of FBXW7 cellular substrates. We further demonstrate that a Tax mutant unable to interact with and inactivate FBXW7 loses its ability to transform primary fibroblasts. Collectively, our results describe a novel mechanism used by a human tumor virus to promote cellular transformation.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas F-Box , Proteína 7 que Contiene Repeticiones F-Box-WD , Productos del Gen tax , Virus Linfotrópico T Tipo 1 Humano , Ubiquitina-Proteína Ligasas , Proteína 7 que Contiene Repeticiones F-Box-WD/metabolismo , Proteína 7 que Contiene Repeticiones F-Box-WD/genética , Humanos , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/metabolismo , Productos del Gen tax/metabolismo , Productos del Gen tax/genética , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Unión Proteica
10.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35210364

RESUMEN

Adult T-cell leukemia/lymphoma (ATL) is an aggressive malignancy caused by human T-cell leukemia virus type 1 (HTLV-1) infection. HTLV-1 exerts its oncogenic functions by interacting with signaling pathways involved in cell proliferation and transformation. Dysregulation of the Hippo/YAP pathway is associated with multiple cancers, including virus-induced malignancies. In the present study, we observe that expression of YAP, which is the key effector of Hippo signaling, is elevated in ATL cells by the action of the HTLV-1 Tax protein. YAP transcriptional activity is remarkably enhanced in HTLV-1-infected cells and ATL patients. In addition, Tax activates the YAP protein via a mechanism involving the NF-κB/p65 pathway. As a mechanism for this cross talk between the Hippo and NF-κB pathways, we found that p65 abrogates the interaction between YAP and LATS1, leading to suppression of YAP phosphorylation, inhibition of ubiquitination-dependent degradation of YAP, and YAP nuclear accumulation. Finally, knockdown of YAP suppresses the proliferation of ATL cells in vitro and tumor formation in ATL-engrafted mice. Taken together, our results suggest that p65-induced YAP activation is essential for ATL pathogenesis and implicate YAP as a potential therapeutic target for ATL treatment.


Asunto(s)
Carcinogénesis , Proteínas de Ciclo Celular/metabolismo , Virus Linfotrópico T Tipo 1 Humano/fisiología , FN-kappa B/metabolismo , Factores de Transcripción/metabolismo , Núcleo Celular/metabolismo , Proliferación Celular , Productos del Gen tax/metabolismo , Humanos , Células Jurkat , Fosforilación , Ubiquitinación , Regulación hacia Arriba
11.
Proc Natl Acad Sci U S A ; 119(24): e2202679119, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35687672

RESUMEN

Following a brief review of the management of environmental externalities under strategic interactions in the traditional temporal domain, results are extended to the spatiotemporal domain. Conditions for spatial open-loop and feedback Nash equilibria, along with conditions for the benchmark cooperative solution, are presented and compared. A simplified numerical example illustrates the spatial patterns emerging at a steady state under Fickian diffusion and dispersal kernels, and the inefficiency of spatially flat emission taxes. This conceptual framework could provide new research areas.

12.
J Infect Dis ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39302694

RESUMEN

HTLV-1 transforms primary CD4+ T cells in vitro within a short time; however, majority of infected individuals maintain an asymptomatic condition, suggesting there is an equilibrium between the infected cells and the host immunity. In this study, we identified a variation in a major viral antigen epitope, HTLV-1 Tax301-309, in HLA-A24-positive individuals. Mismatch in A24/Tax301-309 multimers impaired detection of anti-Tax CTLs. Notably, over half of the TCRs of the anti-Tax CTLs did not recognize mismatched Tax301-309 peptides. These findings highlighted the importance of matching the viral antigen epitope type in T-cell-based immunotherapy against ATL by using viral antigen Tax.

13.
Cancer Sci ; 115(1): 310-320, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37950425

RESUMEN

Human T-cell leukemia virus type 1 (HTLV-1) establishes chronic infection in humans and induces a T-cell malignancy called adult T-cell leukemia-lymphoma (ATL) and several inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Persistent HTLV-1 infection is established under the pressure of host immunity, and therefore the immune response against HTLV-1 is thought to reflect the status of the disease it causes. Indeed, it is known that cellular immunity against viral antigens is suppressed in ATL patients compared to HAM/TSP patients. In this study, we show that profiling the humoral immunity to several HTLV-1 antigens, such as Gag, Env, and Tax, and measuring proviral load are useful tools for classifying disease status and predicting disease development. Using targeted sequencing, we found that several carriers whom this profiling method predicted to be at high risk for developing ATL indeed harbored driver mutations of ATL. The clonality of HTLV-1-infected cells in those carriers was still polyclonal; it is consistent with an early stage of leukemogenesis. Furthermore, this study revealed significance of anti-Gag proteins to predict high risk group in HTLV-1 carriers. Consistent with this finding, anti-Gag cytotoxic T lymphocytes (CTLs) were increased in patients who received hematopoietic stem cell transplantation and achieved remission state, indicating the significance of anti-Gag CTLs for disease control. Our findings suggest that our strategy that combines anti-HTLV-1 antibodies and proviral load may be useful for prediction of the development of HTLV-1-associated diseases.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T del Adulto , Paraparesia Espástica Tropical , Adulto , Humanos , Virus Linfotrópico T Tipo 1 Humano/genética , Provirus/genética , Biomarcadores , Carga Viral
14.
J Hepatol ; 80(4): 543-552, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38092157

RESUMEN

BACKGROUND & AIMS: Chronic liver disease (CLD) causes 1.8% of all deaths in Europe, many of them from liver cancer. We estimated the impact of several policy interventions in France, the Netherlands, and Romania. METHODS: We used a validated microsimulation model to assess seven different policy scenarios in 2022-2030: a minimum unit price (MUP) of alcohol of €0.70 or €1, a volumetric alcohol tax, a sugar-sweetened beverage (SSB) tax, food marketing restrictions, plus two different combinations of these policies compared against current policies (the 'inaction' scenario). RESULTS: All policies reduced the burden of CLD and liver cancer. The largest impact was observed for a MUP of €1, which by 2030 would reduce the cumulative incidence of CLD by between 7.1% to 7.3% in France, the Netherlands, and Romania compared with inaction. For liver cancer, the corresponding reductions in cumulative incidence were between 4.8% to 5.8%. Implementing a package containing a MUP of €0.70, a volumetric alcohol tax, and an SSB tax would reduce the cumulative incidence of CLD by between 4.29% to 4.71% and of liver cancer by between 3.47% to 3.95% in France, the Netherlands, and Romania. The total predicted reduction in healthcare costs by 2030 was greatest with the €1 MUP scenario, with a reduction for liver cancer costs of €8.18M and €612.49M in the Netherlands and France, respectively. CONCLUSIONS: Policy measures tackling primary risk factors for CLD and liver cancer, such as the implementation of a MUP of €1 and/or a MUP of €0.70 plus SSB tax could markedly reduce the number of Europeans with CLD or liver cancer. IMPACT AND IMPLICATIONS: Policymakers must be aware that alcohol and obesity are the two leading risk factors for chronic liver disease and liver cancer in Europe and both are expected to increase in the future if no policy interventions are made. This study assessed the potential of different public health policy measures to mitigate the impact of alcohol consumption and obesity on the general population in three European countries: France, the Netherlands, and Romania. The findings support introducing a €1 minimum unit price for alcohol to reduce the burden of chronic liver disease. In addition, the study shows the importance of targeting multiple drivers of alcohol consumption and obesogenic products simultaneously via a harmonized fiscal policy framework, to complement efforts being made within health systems. These findings should encourage policymakers to introduce such policy measures across Europe to reduce the burden of liver disease. The modeling methods used in this study can assist in structuring similar modeling in other regions to expand on this study's findings.


Asunto(s)
Enfermedades del Sistema Digestivo , Neoplasias Hepáticas , Humanos , Impuestos , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/prevención & control , Obesidad/epidemiología , Obesidad/prevención & control , Etanol , Políticas , Costos de la Atención en Salud , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/prevención & control
15.
EMBO J ; 39(24): e104948, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33226137

RESUMEN

Autophagosome formation requires multiple autophagy-related (ATG) factors. However, we find that a subset of autophagy substrates remains robustly targeted to the lysosome in the absence of several core ATGs, including the LC3 lipidation machinery. To address this unexpected result, we performed genome-wide CRISPR screens identifying genes required for NBR1 flux in ATG7KO cells. We find that ATG7-independent autophagy still requires canonical ATG factors including FIP200. However, in the absence of LC3 lipidation, additional factors are required including TAX1BP1 and TBK1. TAX1BP1's ability to cluster FIP200 around NBR1 cargo and induce local autophagosome formation enforces cargo specificity and replaces the requirement for lipidated LC3. In support of this model, we define a ubiquitin-independent mode of TAX1BP1 recruitment to NBR1 puncta, highlighting that TAX1BP1 recruitment and clustering, rather than ubiquitin binding per se, is critical for function. Collectively, our data provide a mechanistic basis for reports of selective autophagy in cells lacking the lipidation machinery, wherein receptor-mediated clustering of upstream autophagy factors drives continued autophagosome formation.


Asunto(s)
Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Autofagia/genética , Autofagia/fisiología , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Autofagosomas/metabolismo , Proteína 7 Relacionada con la Autofagia/genética , Proteína 7 Relacionada con la Autofagia/metabolismo , Muerte Celular , Análisis por Conglomerados , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células K562 , Lisosomas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Ubiquitina/metabolismo
16.
Proc Biol Sci ; 291(2024): 20240182, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38864335

RESUMEN

In contemporary society, the effective utilization of public resources remains a subject of significant concern. A common issue arises from defectors seeking to obtain an excessive share of these resources for personal gain, potentially leading to resource depletion. To mitigate this tragedy and ensure sustainable development of resources, implementing mechanisms to either reward those who adhere to distribution rules or penalize those who do not, appears advantageous. We introduce two models: a tax-reward model and a tax-punishment model, to address this issue. Our analysis reveals that in the tax-reward model, the evolutionary trajectory of the system is influenced not only by the tax revenue collected but also by the natural growth rate of the resources. Conversely, the tax-punishment model exhibits distinct characteristics when compared with the tax-reward model, notably the potential for bistability. In such scenarios, the selection of initial conditions is critical, as it can determine the system's path. Furthermore, our study identifies instances where the system lacks stable points, exemplified by a limit cycle phenomenon, underscoring the complexity and dynamism inherent in managing public resources using these models.


Asunto(s)
Recompensa , Impuestos , Castigo , Humanos , Modelos Teóricos
17.
Milbank Q ; 102(1): 122-140, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37788392

RESUMEN

Policy Points The Paycheck Plus randomized controlled trial tested a fourfold increase in the Earned Income Tax Credit (EITC) for single adults without dependent children over 3 years in New York and Atlanta. In New York, the intervention improved economic, mental, and physical health outcomes. In Atlanta, it had no economic benefit or impact on physical health and may have worsened mental health. In Atlanta, tax filing and bonus receipt were lower than in the New York arm of the trial, which may explain the lack of economic benefits. Lower mental health scores in the treatment group were driven by disadvantaged men, and the study sample was in good mental health. CONTEXT: The Paycheck Plus experiment examined the effects of an enhanced Earned Income Tax Credit (EITC) for single adults on economic and health outcomes in Atlanta, GA and New York City (NYC). The NYC study was completed two years prior to the Atlanta study and found mental and physical benefits for the subgroups that responded best to the economic incentives provided. In this article, we present the findings from the Atlanta study, in which the uptake of the treatment (tax filings and EITC bonus) were lower and economic and health benefits were not observed. METHODS: Paycheck Plus Atlanta was an unblinded randomized controlled trial that assigned n = 3,971 participants to either the standard federal EITC (control group) or an EITC supplement of up to $2,000 (treatment group) for three tax years (2017-2019). Administrative data on employment and earnings were obtained from the Georgia Department of Labor and survey data were used to examine validated measures of health and well-being. FINDINGS: In Atlanta, the treatment group had significantly higher earnings in the first project year but did not have significantly higher cumulative earnings than the control group overall (mean difference = $1,812, 95% CI = -150, 3,774, p = 0.07). The treatment group also had significantly lower scores on two measures of mental health after the intervention was complete: the Patient Health Questionnaire 8 (mean difference = 0.19, 95% CI = 0.06, 0.32, p = 0.005) and the Kessler 6 (mean difference = 0.15, 95% CI = 0.03, 0.27, p = 0.012). Secondary analyses suggested these results were driven by disadvantaged men, but the study sample was in good mental health. CONCLUSIONS: The EITC experiment in Atlanta was not associated with gains in earnings or improvements in physical or mental health.


Asunto(s)
Impuesto a la Renta , Salud Mental , Masculino , Adulto , Niño , Humanos , Estados Unidos , Renta , Impuestos , Ciudad de Nueva York
18.
Int J Behav Nutr Phys Act ; 21(1): 39, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622655

RESUMEN

BACKGROUND: High consumption of red and processed meat contributes to both health and environmental harms. Warning labels and taxes for red meat reduce selection of red meat overall, but little is known about how these potential policies affect purchases of subcategories of red meat (e.g., processed versus unprocessed) or of non-red-meat foods (e.g., cheese, pulses) relevant to health and environmental outcomes. This study examined consumer responses to warning labels and taxes for red meat in a randomized controlled trial. METHODS: In October 2021, we recruited 3,518 US adults to complete a shopping task in a naturalistic online grocery store. Participants were randomly assigned to one of four arms: control (no warning labels or tax), warning labels only (health and environmental warning labels appeared next to products containing red meat), tax only (prices of products containing red meat were increased 30%) or combined warning labels + tax. Participants selected items to hypothetically purchase, which we categorized into food groups based on the presence of animal- and plant-source ingredients (e.g., beef, eggs, pulses), meat processing level (e.g., processed pork versus unprocessed pork), and meat species (e.g., beef versus pork). We assessed the effects of the warning labels and tax on selections from each food group. RESULTS: Compared to control, all three interventions led participants to select fewer items with processed meat (driven by reductions in processed pork) and (for the tax and warning labels + tax interventions only) fewer items with unprocessed meat (driven by reductions in unprocessed beef). All three interventions also led participants to select more items containing cheese, while only the combined warning labels + tax intervention led participants to select more items containing processed poultry. Except for an increase in selection of pulses in the tax arm, the interventions did not affect selections of fish or seafood (processed or unprocessed), eggs, or plant-based items (pulses, nuts & seeds, tofu, meat mimics, grains & potatoes, vegetables). CONCLUSIONS: Policies to reduce red meat consumption are also likely to affect consumption of other types of foods that are relevant to both health and environmental outcomes. TRIAL REGISTRATION: NCT04716010 on www. CLINICALTRIALS: gov .


Asunto(s)
Carne Roja , Impuestos , Adulto , Humanos , Comportamiento del Consumidor , Etiquetado de Alimentos , Carne
19.
Virus Genes ; 60(2): 117-125, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38273115

RESUMEN

Human T-cell lymphotropic virus type 1 (HTLV-1) is linked to two debilitating diseases, adult T-cell leukemia/lymphoma (ATLL) and HTLV-1 associated myelopathy tropical spastic paraparesis (HAM/TSP), which are prevalent in various parts of the world, including the Alborz province in Iran. Understanding the prevalence and evolutionary relationships of HTLV-1 infections in these endemic areas is of utmost importance. In the realm of phylogenetic studies, long terminal repeat (LTR) region of HTLV-1 stands out as highly conserved, yet more variable compared to other gene segments. Consequently, it is the primary focus for phylogenetic analyses. Additionally, trans-activator of transcription (Tax), an oncoprotein, holds a pivotal role in the regulation of gene expression. This cross-sectional study delved into the phylogenetic analysis of HTLV-1 among individuals in Alborz province of Iran. To confirm infection, we amplified partial sequence LTR (PLTR) and HTLV-1 bZIP factor (PHBZ). For phylogenetic analysis, we sequenced the full sequence LTR (FLTR) and full Tax sequence (FTax). The FLTR and FTax sequences underwent analysis using BioEdit, and phylogenetic trees were constructed using MEGA-X software. Out of the roughly 15,000 annual blood donors in Alborz, 19 samples tested positive for HTLV-1, indicating a 0.13% HTLV-1 positivity rate among blood donors. Furthermore, the HTLV-1 virus prevalent in the Alborz province belongs to subtype A (cosmopolitan) subgroup A. The findings revealed that while mutations were observed in both the LTR and Tax genes, they were not significant enough to bring about fundamental alterations. Despite positive selection detected in three Alborz isolates, it has not led to mutations affecting Tax function and virulence.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Adulto , Humanos , Virus Linfotrópico T Tipo 1 Humano/genética , Filogenia , Irán/epidemiología , Estudios Transversales , Paraparesia Espástica Tropical/epidemiología
20.
Environ Sci Technol ; 58(42): 18484-18495, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39382550

RESUMEN

Hydrogen will potentially play a key role while transitioning to a net-zero economy. This study addresses resource, environmental, economic, policy, and societal issues related to low-carbon hydrogen production by steam methane reforming with carbon capture and storage in Wyoming and other natural-gas-rich states. For low-carbon hydrogen produced from natural gas and electricity supplies and which stores CO2 in saline reservoirs in Wyoming, the levelized cost of hydrogen (LCOH) ranges from $1.62-2.00/kg H2, and the life cycle emissions range from 3.85-5.74 kg CO2-eq/kg H2. If claimed, the 45Q tax credit decreases the LCOH by 19%. Although the supplies of renewable natural gas feedstock and zero- or low-carbon electricity can lower the carbon footprint to make hydrogen projects qualified for the 45V tax credit, the 45Q tax credit is still a stronger economic incentive. To reduce the supply cost, a hydrogen cluster can be developed in the state by leveraging the colocation and coavailability of multiple natural resources and transport infrastructure. Developing a hydrogen cluster can directly create several thousand construction jobs and several hundred permanent jobs in Wyoming. Low-carbon hydrogen production can also be scaled up in other states across the nation.


Asunto(s)
Carbono , Hidrógeno , Gas Natural , Estados Unidos , Wyoming , Metano
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA