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1.
RNA Biol ; 21(1): 1-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38711165

RESUMO

Spliceosome assembly contributes an important but incompletely understood aspect of splicing regulation. Prp45 is a yeast splicing factor which runs as an extended fold through the spliceosome, and which may be important for bringing its components together. We performed a whole genome analysis of the genetic interaction network of the truncated allele of PRP45 (prp45(1-169)) using synthetic genetic array technology and found chromatin remodellers and modifiers as an enriched category. In agreement with related studies, H2A.Z-encoding HTZ1, and the components of SWR1, INO80, and SAGA complexes represented prominent interactors, with htz1 conferring the strongest growth defect. Because the truncation of Prp45 disproportionately affected low copy number transcripts of intron-containing genes, we prepared strains carrying intronless versions of SRB2, VPS75, or HRB1, the most affected cases with transcription-related function. Intron removal from SRB2, but not from the other genes, partly repaired some but not all the growth phenotypes identified in the genetic screen. The interaction of prp45(1-169) and htz1Δ was detectable even in cells with SRB2 intron deleted (srb2Δi). The less truncated variant, prp45(1-330), had a synthetic growth defect with htz1Δ at 16°C, which also persisted in the srb2Δi background. Moreover, htz1Δ enhanced prp45(1-330) dependent pre-mRNA hyper-accumulation of both high and low efficiency splicers, genes ECM33 and COF1, respectively. We conclude that while the expression defects of low expression intron-containing genes contribute to the genetic interactome of prp45(1-169), the genetic interactions between prp45 and htz1 alleles demonstrate the sensitivity of spliceosome assembly, delayed in prp45(1-169), to the chromatin environment.


Assuntos
Íntrons , Fenótipo , Splicing de RNA , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Spliceossomos , Spliceossomos/metabolismo , Spliceossomos/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulação Fúngica da Expressão Gênica , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Histonas/metabolismo , Histonas/genética
2.
Inorg Chem ; 63(13): 5852-5864, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38507718

RESUMO

Four kinds of polyoxometalate (POM)-viologen compounds were synthesized by hydrothermal method, namely (1-cby)2·[H2(SiMo12O40)]·2H2O (1), (1-cby)2·[H2(SiW12O40)]·2H2O (2), (1-cby)2·(1,1'-bcby)2·{H4[Co4(H2O)2(PW9O34)2]}·12H2O (3), (1-cby)·(1,1'-bcby)·[H(α-PW11O39)CoII(1-cby)]·8H2O (4) (1-cby·Br = 1-Cyclopropylmethyl-[4,4']bipyridinyl-1-ium bromide, 1,1'-bcby·Br = 1,1'-Bis-cyclopropylmethyl-[4,4']bipyridinyl-1-ium bromide). These four POM-viologen compounds exhibit one-dimensional supramolecular network structures. Especially, compound 3 contains a rare sandwich POM subunit {Co4(H2O)2(PW9O34)2}10-. These four compounds can be used as color-changing materials, and they all exhibit noticeable color changes upon exposure to light, heat, and electricity. The discoloration mechanism involves viologen derivatives with electron-deficient properties accepting electrons from POM with electron-rich properties under external stimulation, leading to the formation of viologen free radicals. Among them, compounds 1 and 2 also have good properties for ink-free erasable printing, double anticounterfeiting, and ultraviolet detector because of their rapid color response to ultraviolet (UV) light. In addition, compounds 1-4 also show different color changes in the detection of volatile amines.

3.
Nat Commun ; 15(1): 315, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182580

RESUMO

The resilience of cellular proteostasis declines with age, which drives protein aggregation and compromises viability. The nucleus has emerged as a key quality control compartment that handles misfolded proteins produced by the cytosolic protein biosynthesis system. Here, we find that age-associated metabolic cues target the yeast protein disaggregase Hsp104 to the nucleus to maintain a functional nuclear proteome during quiescence. The switch to respiratory metabolism and the accompanying decrease in translation rates direct cytosolic Hsp104 to the nucleus to interact with latent translation initiation factor eIF2 and to suppress protein aggregation. Hindering Hsp104 from entering the nucleus in quiescent cells results in delayed re-entry into the cell cycle due to compromised resumption of protein synthesis. In sum, we report that cytosolic-nuclear partitioning of the Hsp104 disaggregase is a critical mechanism to protect the latent protein synthesis machinery during quiescence in yeast, ensuring the rapid restart of translation once nutrients are replenished.


Assuntos
Proteínas de Choque Térmico , Biossíntese de Proteínas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Ciclo Celular , Divisão Celular , Citosol , Agregados Proteicos , Saccharomyces cerevisiae/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
4.
Int J Mol Sci ; 24(23)2023 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-38069094

RESUMO

Establishing an immune balance between the mother and fetus during gestation is crucial, with the placenta acting as the epicenter of immune tolerance. The placental transfer of antibodies, mainly immunoglobulin G (IgG), is critical in protecting the developing fetus from infections. This review looks at how immunomodulation of antibody glycosylation occurs during placental transfer and how it affects fetal health. The passage of maternal IgG antibodies through the placental layers, including the syncytiotrophoblast, stroma, and fetal endothelium, is discussed. The effect of IgG subclass, glycosylation, concentration, maternal infections, and antigen specificity on antibody transfer efficiency is investigated. FcRn-mediated IgG transport, influenced by pH-dependent binding, is essential for placental transfer. Additionally, this review delves into the impact of glycosylation patterns on antibody functionality, considering both protective and pathological effects. Factors affecting the transfer of protective antibodies, such as maternal vaccination, are discussed along with reducing harmful antibodies. This in-depth examination of placental antibody transfer and glycosylation provides insights into improving neonatal immunity and mitigating the effects of maternal autoimmune and alloimmune conditions.


Assuntos
Imunoglobulina G , Placenta , Gravidez , Feminino , Humanos , Placenta/metabolismo , Glicosilação , Trofoblastos/metabolismo , Imunomodulação , Troca Materno-Fetal
5.
J Cardiovasc Pharmacol Ther ; 28: 10742484231219603, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38099726

RESUMO

Backgrounds: Our study aimed to identify and predict patients with heart failure (HF) taking novel-dose Sacubitril/Valsartan (S/V) at risk for all-cause readmission, as well as investigate the possible role of left ventricular reverse remodeling (LVRR). Methods and results: There were 464 patients recruited from December 2017 to September 2021 in our hospital with a median follow-up of 660 days (range, 17-1494). Competing risk analysis with Gray's Test showed statistically significant differences in all-cause readmission (p-value< .001) across the three different dose groups. Models 1 and 2 were developed based on the results of univariable competing risk analysis, least absolute shrinkage and selection operator approach, backward stepwise regression, and multivariable competing risk analysis. The internal verification (data-splitting method) indicated that Model 1 had better discrimination, calibration, and clinical utility. The corresponding nomogram showed that patients aged 75 years and above, or taking the lowest-dose S/V (≤50 mg twice a day), or diagnosed with ventricular tachycardia, or valvular heart disease, or chronic obstructive pulmonary disease, or diabetes mellitus were at the highest risk of all-cause readmission. In the causal mediation analysis, LVRR was considered as a critical mediator that negatively affected the difference of novel-dose S/V in readmission. Conclusions: A significant association was detected between novel-dose S/V and all-cause readmission in HF patients, in part negatively mediated by LVRR. The web-based nomogram could provide individual prediction of all-cause readmission in HF patients receiving novel-dose S/V. The effects of different novel-dose S/V are still needed to be explored further in the future.


Assuntos
Insuficiência Cardíaca , Readmissão do Paciente , Humanos , Análise de Mediação , Tetrazóis/efeitos adversos , Volume Sistólico , Resultado do Tratamento , Antagonistas de Receptores de Angiotensina/efeitos adversos , Valsartana/efeitos adversos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Combinação de Medicamentos , Função Ventricular Esquerda
6.
Cell Rep ; 42(11): 113372, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37938971

RESUMO

Metacaspases are ancestral homologs of caspases that can either promote cell death or confer cytoprotection. Furthermore, yeast (Saccharomyces cerevisiae) metacaspase Mca1 possesses dual biochemical activity: proteolytic activity causing cell death and cytoprotective, co-chaperone-like activity retarding replicative aging. The molecular mechanism favoring one activity of Mca1 over another remains elusive. Here, we show that this mechanism involves calmodulin binding to the N-terminal pro-domain of Mca1, which prevents its proteolytic activation and promotes co-chaperone-like activity, thus switching from pro-cell death to anti-aging function. The longevity-promoting effect of Mca1 requires the Hsp40 co-chaperone Sis1, which is necessary for Mca1 recruitment to protein aggregates and their clearance. In contrast, proteolytically active Mca1 cleaves Sis1 both in vitro and in vivo, further clarifying molecular mechanism behind a dual role of Mca1 as a cell-death protease versus gerontogene.


Assuntos
Peptídeo Hidrolases , Proteínas de Saccharomyces cerevisiae , Peptídeo Hidrolases/metabolismo , Calmodulina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Caspases/metabolismo , Saccharomyces cerevisiae/metabolismo , Chaperonas Moleculares/metabolismo
7.
Dalton Trans ; 52(38): 13537-13546, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37721162

RESUMO

Hydrothermal synthesis was used to create four different POM-based compounds, namely {[Co(Hptpm)2(ß-Mo8O26)0.5(ξ-Mo8O26)0.5]}·H2O (1), [Co(Hptpm)2(δ-Mo8O26)]·H2O (2), [Co(Hptpm)2(ß-Mo8O26)] (3) and [Zn(Hptpm)2(ß-Mo8O26)] (4) (ptpm = 4-[3-(3-pyridine-2-yl-[1,2,4]triazol-4-yl)-propyl]-morpholine). 1-4 containing different octamolybdate isomers were characterized. Compounds 1-4 showed good electrochemical performance and can be utilized as bifunctional sensors for NO2-, H2O2, Cr(VI) and Fe(III). Taking compound 1 as an example, the detection limits are 0.081 µM for NO2-, 0.072 µM for H2O2, 0.054 µM for Cr(VI) and 0.063 µM for Fe(III), respectively. Compounds 1-4 have good capacitance. Moreover, compounds 1-4 also show good adsorption properties for organic cationic dyes. The cationic dyes include methylene blue (MB), crystal violet (CV) and neutral red (NR). In addition, 1-4 have excellent characteristics that can reduce Cr(VI) to Cr(III) by photocatalytic technology. Within 30 min, the reduction rates were 95.85% for 1, 93.99% for 2, 90.29% for 3 and 88.18% for 4.

8.
Sci Rep ; 13(1): 14068, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640758

RESUMO

ER-to-Golgi trafficking partakes in the sorting of misfolded cytoplasmic proteins to reduce their cytological toxicity. We show here that yeast Sec7, a protein involved in proliferation of the Golgi, is part of this pathway and participates in an Hsp70-dependent formation of insoluble protein deposits (IPOD). Sec7 associates with the disaggregase Hsp104 during a mild heat shock and increases the rate of Hsp104 diffusion in an Hsp70-dependent manner when overproduced. Sec7 overproduction increased formation of IPODs from smaller aggregates and mitigated the toxicity of Huntingtin exon-1 upon heat stress while Sec7 depletion increased sensitivity to aẞ42 of the Alzheimer's disease and α-synuclein of the Parkinson's disease, suggesting a role of Sec7 in mitigating proteotoxicity.


Assuntos
Doença de Alzheimer , Doenças do Sistema Nervoso , Doença de Parkinson , Fermento Seco , Humanos , Saccharomyces cerevisiae/genética , Proteínas de Choque Térmico HSP70/genética
9.
Sci Rep ; 13(1): 9285, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286562

RESUMO

A hallmark of aging in a variety of organisms is a breakdown of proteostasis and an ensuing accumulation of protein aggregates and inclusions. However, it is not clear if the proteostasis network suffers from a uniform breakdown during aging or if some distinct components act as bottlenecks especially sensitive to functional decline. Here, we report on a genome-wide, unbiased, screen for single genes in young cells of budding yeast required to keep the proteome aggregate-free under non-stress conditions as a means to identify potential proteostasis bottlenecks. We found that the GET pathway, required for the insertion of tail-anchored (TA) membrane proteins in the endoplasmic reticulum, is such a bottleneck as single mutations in either GET3, GET2 or GET1 caused accumulation of cytosolic Hsp104- and mitochondria-associated aggregates in nearly all cells when growing at 30 °C (non-stress condition). Further, results generated by a second screen identifying proteins aggregating in GET mutants and analyzing the behavior of cytosolic reporters of misfolding, suggest that there is a general collapse in proteostasis in GET mutants that affects other proteins than TA proteins.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteostase , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo
10.
Nat Commun ; 14(1): 2663, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37160881

RESUMO

Spatial Protein Quality Control (sPQC) sequesters misfolded proteins into specific, organelle-associated inclusions within the cell to control their toxicity. To approach the role of sPQC in cellular fitness, neurodegenerative diseases and aging, we report on the construction of Hsp100-based systems in budding yeast cells, which can artificially target protein aggregates to non-canonical locations. We demonstrate that aggregates of mutant huntingtin (mHtt), the disease-causing agent of Huntington's disease can be artificially targeted to daughter cells as well as to eisosomes and endosomes with this approach. We find that the artificial removal of mHtt inclusions from mother cells protects them from cell death suggesting that even large mHtt inclusions may be cytotoxic, a trait that has been widely debated. In contrast, removing inclusions of endogenous age-associated misfolded proteins does not significantly affect the lifespan of mother cells. We demonstrate also that this approach is able to manipulate mHtt inclusion formation in human cells and has the potential to be useful as an alternative, complementary approach to study the role of sPQC, for example in aging and neurodegenerative disease.


Assuntos
Doenças Neurodegenerativas , Agregados Proteicos , Humanos , Doenças Neurodegenerativas/genética , Envelhecimento , Longevidade , Morte Celular
11.
Lab Med ; 54(5): e117-e120, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36458948

RESUMO

OBJECTIVE: The aim of this study was to retrospectively analyze the etiology of a case of suspected transfusion-related acute lung injury (TRALI) occurring after blood transfusion. METHODS: The clinical symptoms, signs, imaging examinations, and laboratory test results of a patient with suspected TRALI after blood transfusion were retrospectively analyzed, and human leukocyte antigen (HLA) genotyping of the patient and HLA antibodies of the plasma donors were performed. RESULTS: The clinical manifestations of the patient were consistent with those of TRALI after blood transfusion. This TRALI was treated by timely ventilator support. The patient results of high-resolution HLA genotyping were HLA-A* 01:01, 11:01; HLA-B* 15:02, 37:01; HLA-C* 06:02, 08:01; DRB1* 10:01, 12:02; DRB3* 03:01, 03:01; DQA1* 01:05, 06:01; DQB1* 03:01, 05:01; DPA1* 01:03, 02:01; and DPB1* 02:01, 09:01. Of the 6 plasma donors tested, 3 were found to have HLA-II antibodies, which were HLA-DPA1*01:03, HLA-DQB1*03:01, and HLA-DQB1*03:01 antibodies. CONCLUSION: We described a case of TRALI caused by HLA-DQB1*03:01 antibody and DPA1*01:03 antibody.


Assuntos
Lesão Pulmonar Aguda Relacionada à Transfusão , Humanos , Lesão Pulmonar Aguda Relacionada à Transfusão/diagnóstico , Estudos Retrospectivos , Anticorpos , Doadores de Sangue
12.
PLoS One ; 17(11): e0272742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36441714

RESUMO

China is determined to accomplish universal preschool education by asking the kindergartens to participate in social responsibility programs. This study intends to assess the level of participation of inclusive kindergartens in social responsibility programs. This study uses the Delphi expert method, integrated ISO26000 International Standard Guidelines for Social Responsibility, CSR (Corporate Social Responsibility) Scale, and the characteristics of the preschool education industry to construct a social responsibility evaluation model for inclusive kindergartens. It includes five dimensions (responsibility management, customer responsibility, employee responsibility, social service, and organizational responsibility) to show the social responsibility status of kindergartens. Data was collected from 832 respondents from 27 provinces, cities, and regions in China. This study reveals that the overall performance of social responsibility of inclusive kindergarten (3.67) is better, while organization responsibility (3.91) shows the highest performance. In comparison, customer (3.63) and staff responsibility (3.63) deliver average performance, and responsibility management (3.56) offers lower performance. The statistical analysis shows that the nature of kindergartens, whether inclusive or not, the number of classes, years of establishment, the distribution area, and performance are different. Kindergartens should have certain social values, including specific behaviors and participating in social activities in the spirit of social service. They should ensure preschool teacher's professional and vocational development through multiple subjects' synergetic governance. In addition to fulfilling the teachers' social responsibility and professional development, the findings can put forward the cooperation with the government, social organizations, and kindergartens to improve teachers' professional quality and social responsibility.


Assuntos
Professores Escolares , Instituições Acadêmicas , Pré-Escolar , Humanos , Escolaridade , Responsabilidade Social , China
13.
Nat Commun ; 13(1): 3701, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35764627

RESUMO

Stress granules (SGs) are non-membranous organelles facilitating stress responses and linking the pathology of age-related diseases. In a genome-wide imaging-based phenomic screen, we identify Pab1 co-localizing proteins under 2-deoxy-D-glucose (2-DG) induced stress in Saccharomyces cerevisiae. We find that deletion of one of the Pab1 co-localizing proteins, Lsm7, leads to a significant decrease in SG formation. Under 2-DG stress, Lsm7 rapidly forms foci that assist in SG formation. The Lsm7 foci form via liquid-liquid phase separation, and the intrinsically disordered region and the hydrophobic clusters within the Lsm7 sequence are the internal driving forces in promoting Lsm7 phase separation. The dynamic Lsm7 phase-separated condensates appear to work as seeding scaffolds, promoting Pab1 demixing and subsequent SG initiation, seemingly mediated by RNA interactions. The SG initiation mechanism, via Lsm7 phase separation, identified in this work provides valuable clues for understanding the mechanisms underlying SG formation and SG-associated human diseases.


Assuntos
Fenômenos Bioquímicos , Proteínas de Saccharomyces cerevisiae , Grânulos Citoplasmáticos/metabolismo , Humanos , Proteínas de Ligação a Poli(A)/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Grânulos de Estresse
14.
Healthcare (Basel) ; 10(5)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35628092

RESUMO

The outbreak of COVID-19 epidemic has been having a great impact on the job market, so that graduates from all over the world are facing a more complex employment environment. Unemployment of the educated labor force often results in a waste of human capital and leads to serious economic and social problems. In the face of the impact of COVID-19, the Chinese government quickly introduced a series of employment policies for college graduates to relieve their employment pressure and create opportunities of career development. How did these employment policies for college graduates spread rapidly under the unconventional state of the COVID-19 epidemic? What are the diffusion characteristics? What are the core issues and measures? What are the differences between governments at all levels? These problems with rich connotation and research value needed to be further clarified. Based on the 72 employment support policies collected from the Chinese government network, this paper conducted a text analysis of the policies and found that in the process dimension, the employment policies of college graduates accumulated and exploded from bottom to top in the short term, and the policies diffusion followed the gradual model of "east-middle-west". In the content dimension, there were five core issues: financial subsidies, innovation and entrepreneurship to drive employment, public institutions to absorb, optimizing public services, and lowering the support threshold. Meanwhile, there were obvious differences in the choice of policy tools, policy intensity, and implementation ideas in each region. The findings are of important significance for developed and developing countries to better respond to the impact of various emergency situations.

15.
Front Psychol ; 13: 810719, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356335

RESUMO

China set the goal of expanding early childhood education (ECE) in 2018, by encouraging the development of public interest kindergartens (PIK) to provide high-quality, low-cost preschool services to the general public. This is in response to the challenges of accessibility, affordability, and accountability besetting China's current ECE system. However, the transition toward PIK has been slow due to various complex problems, including the lackluster willingness of ECE providers to become PIK. To better understand the challenges leading to low participation, this study explores the external pressures affecting ECE providers and evaluates the external factors that influence their level of social responsibility. A stratified-random sampling questionnaire survey solicited responses from 832 ECE personnel representing 261 kindergartens from across China. Our findings suggest that institutional pressure has a positive effect on social responsibility and inclusive participation. We also found that institution visibility positively regulates the relationship between institutional pressure and social responsibility. At the same time, the level of environmental perception positively governs the relationship between social responsibility and participation willingness. Kindergartens should have certain social values, including assuming certain behaviors and participating in social activities in the spirit of social service and ensure multiple subjects' synergetic governance.

16.
Open Life Sci ; 16(1): 602-610, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34183992

RESUMO

BACKGROUND: The current study investigates the effect of transcription factor Prox1 on the proliferation, migration, and invasion ability of lung cancer. METHODS: Lung cancer cell lines (A549 and H446 cells) were transfected with Prox1NAD and siRNA, respectively. Thus, the A549 and H446 cells overexpressed Prox1 after transfection of Prox1NAD plasmids, and A549 and H446 cells have low expression of Prox1 after transfection with siRNA. Reverse transcriptase quantitative PCR and western blot analyses were used to detect Prox1 mRNA and protein expression in cells. Plate clone formation experiments and MTT experiments were used to detect cell proliferation. Western blot was used to detect the expression of Rho family-related proteins in cells. RESULTS: Compared to untransfected wild-type A549 and H446 that served as blank controls, the expression level of Prox1mRNA and protein in A549 and H446 cells overexpressing Prox1 after plasmid transfection was high, while the expression level of Prox1mRNA and protein in A549 and H446 cells with low expression of Prox1 after siRNA transfection was low. With the increase of Prox1 expression, the expression of RhoA and RhoC increased, while the expression of RhoB decreased. CONCLUSION: The finding of this study may provide a new approach for the treatment of lung cancer using targeted gene therapy.

17.
Cell Rep ; 35(13): 109328, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34192536

RESUMO

In this paper, we show that the essential Hsp90 co-chaperone Sgt1 is a member of a general protein quality control network that links folding and degradation through its participation in the degradation of misfolded proteins both in the cytosol and the endoplasmic reticulum (ER). Sgt1-dependent protein degradation acts in a parallel pathway to the ubiquitin ligase (E3) and ubiquitin chain elongase (E4), Hul5, and overproduction of Hul5 partly suppresses defects in cells with reduced Sgt1 activity. Upon proteostatic stress, Sgt1 accumulates transiently, in an Hsp90- and proteasome-dependent manner, with quality control sites (Q-bodies) of both yeast and human cells that co-localize with Vps13, a protein that creates organelle contact sites. Misfolding disease proteins, such as synphilin-1 involved in Parkinson's disease, are also sequestered to these compartments and require Sgt1 for their clearance.


Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Dobramento de Proteína , Proteólise , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Citosol/metabolismo , Retículo Endoplasmático/metabolismo , Genes Fúngicos , Células HeLa , Humanos , Mutação/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Agregados Proteicos , Ligação Proteica , Saccharomyces cerevisiae/genética
18.
J Cell Sci ; 134(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34085697

RESUMO

The toxic metalloid arsenic causes widespread misfolding and aggregation of cellular proteins. How these protein aggregates are formed in vivo, the mechanisms by which they affect cells and how cells prevent their accumulation is not fully understood. To find components involved in these processes, we performed a genome-wide imaging screen and identified Saccharomyces cerevisiae deletion mutants with either enhanced or reduced protein aggregation levels during arsenite exposure. We show that many of the identified factors are crucial to safeguard protein homeostasis (proteostasis) and to protect cells against arsenite toxicity. The hits were enriched for various functions including protein biosynthesis and transcription, and dedicated follow-up experiments highlight the importance of accurate transcriptional and translational control for mitigating protein aggregation and toxicity during arsenite stress. Some of the hits are associated with pathological conditions, suggesting that arsenite-induced protein aggregation may affect disease processes. The broad network of cellular systems that impinge on proteostasis during arsenic stress identified in this current study provides a valuable resource and a framework for further elucidation of the mechanistic details of metalloid toxicity and pathogenesis. This article has an associated First Person interview with the first authors of the paper.


Assuntos
Arsênio , Arsenitos , Proteínas de Saccharomyces cerevisiae , Arsenitos/toxicidade , Agregados Proteicos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
20.
J Mater Chem B ; 8(23): 5052-5063, 2020 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-32400816

RESUMO

The major obstacle that hinders current cancer immunotherapies is the development of an effective approach to promote a proper immune response for effective tumor killing through activated T cells. Herein, we report an effective T cell-based tumor immunotherapy approach through nonviral delivery of a cytosine-guanine (CpG) oligonucleotide using dendrimer-entrapped gold nanoparticles (Au DENPs). In our work, Au DENPs partially decorated with methoxy polyethylene glycol (mPEG) were synthesized and characterized to be used as a vector for CpG delivery to bone marrow-derived dendritic cells (BMDCs). The BMDCs matured via CpG delivery were used to activate T cells for adoptive immunotherapy of cancer cells. We show that the developed PEGylated Au DENPs are able to effectively transfect CpG leading to the maturation of BMDCs that can be used to activate T cells for subsequent adoptive immunotherapy of cancer cells in vitro and a xenografted melanoma tumor model in vivo after intravenous injection. Importantly, the developed approach to genetically engineer BMDCs enables a triggered adaptive immune response and memory of T cells, which can be beneficial for effective inhibition of tumor metastasis and recurrence. The developed nonviral gene delivery approach using Au DENPs as a vector for T cell-based immunotherapy can be applied to different cancer types.


Assuntos
Citosina/química , Dendrímeros/química , Células Dendríticas/química , Terapia Genética , Guanina/química , Imunoterapia Adotiva , Melanoma Experimental/terapia , Animais , Dendrímeros/síntese química , Feminino , Vetores Genéticos/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Propriedades de Superfície
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