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1.
Mol Cell ; 80(4): 607-620.e12, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33113344

RESUMO

Aberrant mitophagy has been implicated in a broad spectrum of disorders. PINK1, Parkin, and ubiquitin have pivotal roles in priming mitophagy. However, the entire regulatory landscape and the precise control mechanisms of mitophagy remain to be elucidated. Here, we uncover fundamental mitophagy regulation involving PINK1 and a non-canonical role of the mitochondrial Tu translation elongation factor (TUFm). The mitochondrion-cytosol dual-localized TUFm interacts with PINK1 biochemically and genetically, which is an evolutionarily conserved Parkin-independent route toward mitophagy. A PINK1-dependent TUFm phosphoswitch at Ser222 determines conversion from activating to suppressing mitophagy. PINK1 modulates differential translocation of TUFm because p-S222-TUFm is restricted predominantly to the cytosol, where it inhibits mitophagy by impeding Atg5-Atg12 formation. The self-antagonizing feature of PINK1/TUFm is critical for the robustness of mitophagy regulation, achieved by the unique kinetic parameters of p-S222-TUFm, p-S65-ubiquitin, and their common kinase PINK1. Our findings provide new mechanistic insights into mitophagy and mitophagy-associated disorders.


Assuntos
Drosophila melanogaster/crescimento & desenvolvimento , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Mitofagia , Fator Tu de Elongação de Peptídeos/metabolismo , Proteínas Quinases/metabolismo , Animais , Citosol/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Células HeLa , Humanos , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Fator Tu de Elongação de Peptídeos/genética , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Proteínas Quinases/genética , Transporte Proteico , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
J Endovasc Ther ; : 15266028231165725, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37050852

RESUMO

PURPOSE: Isolated infected iliac artery aneurysms (IIIAAs) are extremely rare, life-threatening, and intractable. This study aimed to evaluate the outcomes of endovascular treatment in patients with IIIAAs. METHODS: A retrospective study was conducted for all patients who underwent endovascular treatment for IIIAAs between June 2012 and June 2022 in 3 hospitals. The clinical data and follow-up outcomes were reviewed and assessed. RESULTS: Fifteen patients were included in this study. The median age was 69 years, 12 patients (80%) were men, and 8 (53%) had hypertension. Most of the patients presented with abdominal or lumbar pain (87%) and fever (60%). The offending pathogen was identified in 11 patients (73%). Fifteen patients had a total of 16 IIIAAs, with 12 (75%) involving the common iliac artery. The immediate technical success rate was 100%, and the 30-day mortality was 7%. Infection-related complications occurred in 2 patients (13%) during hospitalization who were treated by open surgery at a later stage. The median follow-up was 23 months (range: 6-80 months, mean: 32 ± 25 months). Aneurysm recurrence was identified in one patient (7%) 5 months after endovascular repair. It was managed by endovascular stent-graft repair with percutaneous catheter drainage. No patients died during the follow-up period. CONCLUSION: Endovascular treatment is feasible, safe, and effective for patients with IIIAAs, achieving acceptable clinical outcomes. Infection surveillance with essential reintervention should be considered for potential infection-related complications. CLINICAL IMPACT: This study first reported that 15 patients underwent endovascular treatment for primary isolated infected iliac artery aneurysms (IIIAAs). It showed a good early and midterm outcomes. This is the first and largest multi-center study and the first literature review of IIIAAs. It provides an evidence that endovascular treatment is feasible, safe, and effective to treat IIIAAs. It suggests endovascular treatment is a promising alternative or a bridge to conventional open surgery for IIIAAs. This may promote endovascular therapy in the management of IIIAAs. It would help clinicians to make an appropriate treatment choice for IIIAAs.

3.
Heart Surg Forum ; 26(3): E292-E302, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37401427

RESUMO

Emboli caused by cardiac myxomas mostly occur in the cardiovascular or cerebrovascular systems and rarely in the lower extremity vasculature. We introduce the rare case of a patient with left atrial myxoma (LAM) whose right lower extremity (RLE) suffered from acute ischemia due to tumor fragments, along with a review of the relevant literature, and highlight the clinical characteristics of LAM. An 81-year-old female presented with acute ischemia of RLE. Color Doppler ultrasound showed no blood flow signal far from the RLE femoral artery. Computed tomography angiography showed an occlusion of the right common femoral artery. A transthoracic echocardiogram revealed a left atrial mass. Femoral artery embolectomy was performed under local anesthesia, followed by thoracotomy with tumor resection under general anesthesia on postoperative day seven. The tumor was pathologically confirmed as an atrial myxoma. A literature search of the PubMed database returned 58 cases of limb ischemia due to LAM, and the conclusions drawn from the statistical analysis were that emboli from LAM occurred most commonly in the aortoiliac and bilateral lower limb vasculature and were rarely associated with upper extremity and atrial fibrillation. Multisystem embolism is characteristic of cardiac myxoma. The removed embolus should be examined pathologically for signs of a cardiac myxoma. Lower-limb embolisms should be promptly diagnosed and treated to avoid osteofascial compartment syndrome.


Assuntos
Arteriopatias Oclusivas , Fibrilação Atrial , Embolia , Neoplasias Cardíacas , Mixoma , Doenças Vasculares Periféricas , Feminino , Humanos , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Isquemia/diagnóstico , Isquemia/etiologia , Isquemia/cirurgia , Embolia/diagnóstico , Embolia/etiologia , Embolia/cirurgia , Extremidade Inferior/irrigação sanguínea , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Átrios do Coração/cirurgia , Doenças Vasculares Periféricas/complicações , Mixoma/complicações , Mixoma/diagnóstico , Mixoma/cirurgia
4.
J Clin Biochem Nutr ; 73(2): 116-123, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37700850

RESUMO

A widespread degenerative condition of the aorta, abdominal aortic aneurysm (AAA), severely endangers the health of middle-aged and elderly people. SPARC related modular calcium binding2 (SMOC2) is upregulated in the carotid arteries of rats with atherosclerotic lesions, but its function in AAA is still unknown. Therefore, the aim of this research was to evaluate the function of SMOC2 in AAA. The results showed that in the AAA tissues, SMOC2 expression was upregulated compared with healthy controls. Overexpression of SMOC2 promoted vascular smooth muscle cells (VSMCs) proliferation, migration, and extracellular matrix (ECM) degradation. In contrast, silence of SMOC2 inhibited VSMCs proliferation, migration, and ECM degradation. Overexpression of SMOC2 promoted BMP and TGF-ß1 expression and silence of SMOC2 had an opposite effect. Besides, inhibition of BMP or TGF-ß1 suppressed VSMCs cell proliferation, migration, and ECM degradation. Moreover, inhibition BMP or TGF-ß1 reversed the promotive effects of SMOC2 overexpression on VSMCs proliferation, migration, and ECM degradation. SMOC2 may affecte the formation of AAA by upregulating BMP and TGF-ß1 to regulate the proliferation, migration, and ECM degradation of VSMCs.

5.
Nucleic Acids Res ; 48(10): e57, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32232370

RESUMO

Site-specific DNA double-strand breaks have been used to generate knock-in through the homology-dependent or -independent pathway. However, low efficiency and accompanying negative impacts such as undesirable indels or tumorigenic potential remain problematic. In this study, we present an enhanced reduced-risk genome editing strategy we named as NEO, which used either site-specific trans or cis double-nicking facilitated by four bacterial recombination factors (RecOFAR). In comparison to currently available approaches, NEO achieved higher knock-in (KI) germline transmission frequency (improving from zero to up to 10% efficiency with an average of 5-fold improvement for 8 loci) and 'cleaner' knock-in of long DNA fragments (up to 5.5 kb) into a variety of genome regions in zebrafish, mice and rats. Furthermore, NEO yielded up to 50% knock-in in monkey embryos and 20% relative integration efficiency in non-dividing primary human peripheral blood lymphocytes (hPBLCs). Remarkably, both on-target and off-target indels were effectively suppressed by NEO. NEO may also be used to introduce low-risk unrestricted point mutations effectively and precisely. Therefore, by balancing efficiency with safety and quality, the NEO method reported here shows substantial potential and improves the in vivo gene-editing strategies that have recently been developed.


Assuntos
Proteínas de Bactérias/metabolismo , Edição de Genes/métodos , Animais , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/metabolismo , Feminino , Técnicas de Introdução de Genes , Genômica , Recombinação Homóloga , Humanos , Mutação INDEL , Macaca fascicularis , Camundongos , Ratos Sprague-Dawley , Recombinases Rec A/metabolismo , Peixe-Zebra/genética
6.
Nat Methods ; 14(7): 720-728, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28581494

RESUMO

Reduced nicotinamide adenine dinucleotide phosphate (NADPH) is essential for biosynthetic reactions and antioxidant functions; however, detection of NADPH metabolism in living cells remains technically challenging. We develop and characterize ratiometric, pH-resistant, genetically encoded fluorescent indicators for NADPH (iNap sensors) with various affinities and wide dynamic range. iNap sensors enabled quantification of cytosolic and mitochondrial NADPH pools that are controlled by cytosolic NAD+ kinase levels and revealed cellular NADPH dynamics under oxidative stress depending on glucose availability. We found that mammalian cells have a strong tendency to maintain physiological NADPH homeostasis, which is regulated by glucose-6-phosphate dehydrogenase and AMP kinase. Moreover, using the iNap sensors we monitor NADPH fluctuations during the activation of macrophage cells or wound response in vivo. These data demonstrate that the iNap sensors will be valuable tools for monitoring NADPH dynamics in live cells and gaining new insights into cell metabolism.


Assuntos
Regulação da Expressão Gênica/fisiologia , Proteínas Luminescentes/metabolismo , NADP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Sobrevivência Celular , Glucose , Homeostase , Humanos , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Camundongos , Modelos Moleculares , Estresse Oxidativo , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Engenharia de Proteínas
7.
Biosci Biotechnol Biochem ; 84(9): 1788-1798, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32448038

RESUMO

Many phenolic compounds, derived from lignin during the pretreatment of lignocellulosic biomass, could obviously inhibit the activity of cellulolytic and hemicellulolytic enzymes. Acetosyringone (AS) is one of the phenolic compounds produced from lignin degradation. In this study, we investigated the inhibitory effects of AS on xylanase activity through kinetic experiments. The results showed that AS could obviously inhibit the activity of xylanase in a reversible and noncompetitive binding manner (up to 50% activity loss). Inhibitory kinetics and constants of xylanase on AS were conducted by the HCH-1 model (ß = 0.0090 ± 0.0009 mM-1). Furthermore, intrinsic and 8-anilino-1-naphthalenesulfonic (ANS)-binding fluorescence results showed that the tertiary structure of AS-mediated xylanase was altered. These findings provide new insights into the role of AS in xylanase activity. Our results also suggest that AS was an inhibitor of xylanase and targeting AS was a potential strategy to increase xylose production.


Assuntos
Acetofenonas/farmacologia , Endo-1,4-beta-Xilanases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Polissacarídeos/metabolismo , Hidrólise/efeitos dos fármacos , Cinética
8.
Biochem Biophys Res Commun ; 502(2): 250-254, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-29803677

RESUMO

Adenosine kinase (ADK) plays an important role in the growth and development of organisms. A convenient, quick, reliable, sensitive and low-cost assay for ADK activity is of great significance. Here, we found the reaction system with bromothymol blue as the pH indicator had a maximum absorption peak at 614 nm. The absorbance change in 614 nm was positively correlated with the generated hydrogen ions in the reaction catalyzed by ADK. Then, we demonstrated this assay was feasible for ADK activity. Further, we analyzed the effects of buffer, bromothymol blue concentrations on the sensitivity of the assay, and investigated the sensitivity of ADK contents and adenosine concentration on the assay. Finally, we calculated the Km and Vmax of ADK from Bombyx mori with this assay. Our results suggested this assay was quick, convenient, reliable, sensitive and economic for the activity of ADK. It is an excellent alternative for the conventional ADK assays.


Assuntos
Adenosina Quinase/análise , Colorimetria/métodos , Adenosina Quinase/química , Adenosina Quinase/metabolismo , Animais , Bombyx/enzimologia , Azul de Bromofenol , Azul de Bromotimol , Soluções Tampão , Colorimetria/estatística & dados numéricos , Corantes , Estudos de Viabilidade , Concentração de Íons de Hidrogênio , Cinética , Espectrofotometria
9.
Arch Insect Biochem Physiol ; 98(3): e21463, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29569264

RESUMO

Alpha-tubulin N-acetyltransferase 1 (ATAT1) is an acetyltransferase specific to α-tubulin and performs important functions in many cellular processes. Bombyx mori is an economic insect and also known as a model lepidoptera insect. In this study, we cloned a B. mori ATAT1 gene (BmATAT1) (Gen Bank accession number: XP_004932777.1). BmATAT1 contained an open reading frame (ORF) of 1,065 bp encoding 355 amino acids (aa). Expression profiling of BmATAT1 protein showed that the expression levels of BmATAT1 at different developmental stages and different tissues in fifth-instar larvae differ. BmATAT1 was highly expressed at the egg stage and in the head of the fifth-instar larvae. Subcellular localization showed that BmATAT1 was distributed in the cytoplasm and nucleus. Furthermore, BmATAT1 may lead to time-dependent induction of cell cycle arrest in the G2/M phase by flow cytometry analysis. Interestingly, using site-specific mutation, immunoprecipitation, and Western blotting, we further found a BmATAT1 acetylated site at K156, suggesting that this acetyltransferase could be regulated by acetylation itself.


Assuntos
Acetiltransferases/metabolismo , Bombyx/enzimologia , Tubulina (Proteína)/metabolismo , Animais , Ciclo Celular , Proteínas de Insetos/metabolismo , Larva/enzimologia
10.
Br J Cancer ; 115(10): 1253-1263, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27736841

RESUMO

BACKGROUND: Improved mesothelioma patient survival will require development of novel and more effective pharmacological interventions. TP53 genomic mutations are uncommon in mesothelioma, and recent data indicate that p53 remains functional, and therefore is a potential therapeutic target in these cancers. In addition, the tumour suppressor NF2 is inactivated by genomic mechanisms in more than 80% of mesothelioma, causing upregulation of FAK activity. Because FAK is a negative regulator of p53, NF2 regulation of FAK-p53-MDM2 signalling loops were evaluated. METHODS: Interactions of FAK-p53 or NF2-FAK were evaluated by phosphotyrosine-p53 immunoaffinity purification and tandem mass spectrometry, and p53, FAK, and NF2 immunoprecipitations. Activation and/or expression of FAK, p53, and NF2 were also evaluated in mesotheliomas. Effects of combination MDM2 and FAK inhibitors/shRNAs were assessed by measuring mesothelioma cell viability/growth, expression of cell cycle checkpoints, and cell cycle alterations. RESULTS: We observed constitutive activation of FAK, a known negative regulator of p53, in each of 10 mesothelioma cell lines and each of nine mesothelioma surgical specimens, and FAK was associated with p53 in five of five mesothelioma cell lines. In four mesotheliomas with wild-type p53, FAK silencing by RNAi induced expression and phosphorylation of p53. However, FAK regulation of mesothelioma proliferation was not restricted to p53-dependent pathways, as demonstrated by immunoblots after FAK knockdown in JMN1B mesothelioma cells, which have mutant/inactivated p53, compared with four mesothelioma cell lines with nonmutant p53. Additive effects were obtained through a coordinated reactivation of p53, by FAK knockdown/inhibition and MDM2 inhibition, as demonstrated by immunoblots, cell viability, and cell-cycle analyses, showing increased p53 expression, apoptosis, anti-proliferative effects, and cell-cycle arrest, as compared with either intervention alone. Our results also indicate that NF2 regulates the interaction of FAK-p53 and MDM2-p53. CONCLUSIONS: These findings highlight novel therapeutic opportunities in mesothelioma.


Assuntos
Proliferação de Células/genética , Quinase 1 de Adesão Focal/genética , Mesotelioma/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Genes Supressores de Tumor/fisiologia , Humanos , Mesotelioma/patologia , Mutação/genética , Neurofibromina 2/genética , Fosforilação/genética , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética , Transdução de Sinais/genética
11.
Nat Commun ; 15(1): 3901, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724505

RESUMO

Activation of the NF-κB pathway is strictly regulated to prevent excessive inflammatory and immune responses. In a well-known negative feedback model, IκBα-dependent NF-κB termination is a delayed response pattern in the later stage of activation, and the mechanisms mediating the rapid termination of active NF-κB remain unclear. Here, we showed IκBα-independent rapid termination of nuclear NF-κB mediated by CLK2, which negatively regulated active NF-κB by phosphorylating the RelA/p65 subunit of NF-κB at Ser180 in the nucleus to limit its transcriptional activation through degradation and nuclear export. Depletion of CLK2 increased the production of inflammatory cytokines, reduced viral replication and increased the survival of the mice. Mechanistically, CLK2 phosphorylated RelA/p65 at Ser180 in the nucleus, leading to ubiquitin‒proteasome-mediated degradation and cytoplasmic redistribution. Importantly, a CLK2 inhibitor promoted cytokine production, reduced viral replication, and accelerated murine psoriasis. This study revealed an IκBα-independent mechanism of early-stage termination of NF-κB in which phosphorylated Ser180 RelA/p65 turned off posttranslational modifications associated with transcriptional activation, ultimately resulting in the degradation and nuclear export of RelA/p65 to inhibit excessive inflammatory activation. Our findings showed that the phosphorylation of RelA/p65 at Ser180 in the nucleus inhibits early-stage NF-κB activation, thereby mediating the negative regulation of NF-κB.


Assuntos
Citoplasma , Inibidor de NF-kappaB alfa , NF-kappa B , Proteínas Tirosina Quinases , Fator de Transcrição RelA , Animais , Fosforilação , Inibidor de NF-kappaB alfa/metabolismo , Inibidor de NF-kappaB alfa/genética , Camundongos , Fator de Transcrição RelA/metabolismo , Humanos , Proteínas Tirosina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , NF-kappa B/metabolismo , Citoplasma/metabolismo , Proteólise , Núcleo Celular/metabolismo , Replicação Viral , Células HEK293 , Transdução de Sinais , Camundongos Endogâmicos C57BL , Citocinas/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas Serina-Treonina Quinases
12.
Dev Cell ; 59(3): 384-399.e5, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38198890

RESUMO

Different types of cells uptake fatty acids in response to different stimuli or physiological conditions; however, little is known about context-specific regulation of fatty acid uptake. Here, we show that muscle injury induces fatty acid uptake in muscle stem cells (MuSCs) to promote their proliferation and muscle regeneration. In humans and mice, fatty acids are mobilized after muscle injury. Through CD36, fatty acids function as both fuels and growth signals to promote MuSC proliferation. Mechanistically, injury triggers the translocation of CD36 in MuSCs, which relies on dynamic palmitoylation of STX11. Palmitoylation facilitates the formation of STX11/SNAP23/VAMP4 SANRE complex, which stimulates the fusion of CD36- and STX11-containing vesicles. Restricting fatty acid supply, blocking fatty acid uptake, or inhibiting STX11 palmitoylation attenuates muscle regeneration in mice. Our studies have identified a critical role of fatty acids in muscle regeneration and shed light on context-specific regulation of fatty acid sensing and uptake.


Assuntos
Ácidos Graxos , Lipoilação , Músculo Esquelético , Proteínas Qa-SNARE , Regeneração , Animais , Humanos , Camundongos , Transporte Biológico , Antígenos CD36/metabolismo , Membrana Celular/metabolismo , Ácidos Graxos/metabolismo , Músculo Esquelético/lesões , Músculo Esquelético/fisiologia , Proteínas Qa-SNARE/metabolismo
13.
Biochem J ; 441(2): 623-32, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21967612

RESUMO

The formation of intracellular nitrogen-based oxidants has important physiological and pathological consequences. CK (creatine kinase), which plays a key role in intracellular energy metabolism, is a main target of low concentrations of oxidative and nitrative stresses. In the present study, the interaction between cytosolic CKs [MM-CK (muscle-type CK) and BB-CK (brain-type CK)] and MTs [metallothioneins; hMT2A (human MT-IIA) and hMT3 (human MT-III)] were characterized by both in vitro and intact-cell assays. MTs could successfully protect the cytosolic CKs against inactivation induced by low concentrations of PN (peroxynitrite) and NO both in vitro and in hMT2A-overexpressing H9c2 cells and hMT3-knockdown U-87 MG cells. Under high PN concentrations, CK formed granule-like structures, and MTs were well co-localized in these aggregated granules. Further analysis indicated that the number of cells containing the CK aggregates negatively correlated with the expression levels of MTs. In vitro experiments indicated that MTs could effectively protect CKs against aggregation during refolding, suggesting that MT might function as a chaperone to assist CK re-activation. The findings of the present study provide direct evidence of the connection between the two well-characterized intracellular systems: the precisely balanced energy homoeostasis by CKs and the oxidative-stress response system using MTs.


Assuntos
Creatina Quinase Forma BB/metabolismo , Creatina Quinase Forma MM/metabolismo , Metalotioneína/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Óxido Nítrico/farmacologia , Ácido Peroxinitroso/farmacologia , Animais , Células CHO , Creatina Quinase Forma BB/antagonistas & inibidores , Creatina Quinase Forma MM/antagonistas & inibidores , Cricetinae , Citosol/enzimologia , Humanos , Metalotioneína 3 , Camundongos , Chaperonas Moleculares/farmacologia
14.
Prep Biochem Biotechnol ; 43(3): 271-84, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23379274

RESUMO

Microwaves have been used as a mutant agent to select mutant strains with high-yield and high-purity pigment. Mass spectrometry and nuclear magnetic resonance spectroscopic techniques were used to elucidate the structures of the pigment. High-performance liquid chromatography was used to measure pigment purity. The analysis of the mutant strain showed that pigment yield increased by 109% and was 98% pure. Prodigiosin in ethanol solution had good stability under ambient temperature and natural indoor light. However, prodigiosin rapidly decomposed under intense sunlight. Prodigiosin is an ecological colorant to dye fabrics, including synthetic and natural fibers. Synthetic fabrics dyed with prodigiosin, such as polyamide and acrylic, have high colorfastness to washing (≥4th grade) and antimicrobial properties (>90%) against Escherichia coli and Staphylococcus aureus. Antimicrobial properties were significantly different between synthetic and natural fabrics. The mutant strain Serratia marcescens jx1-1, with high prodigiosin yield and purity, has promising prospects in food, cosmetic, and textile industries.


Assuntos
Antibacterianos/farmacologia , Corantes/química , Prodigiosina/biossíntese , Prodigiosina/farmacologia , Serratia marcescens/genética , Serratia marcescens/metabolismo , Escherichia coli/efeitos dos fármacos , Micro-Ondas , Mutação , Prodigiosina/química , Prodigiosina/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Indústria Têxtil
15.
Cell Death Differ ; 30(2): 500-514, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36481789

RESUMO

The Cancer/Testis Antigen (CTA) genes comprise a group of genes whose expression under physiological conditions is restricted to the testis but is activated in many human cancers. Depending on the particular expression pattern, the CTA genes are speculated to play a role in spermatogenesis, but evidence is limited thus far. Here, we reported patients with a hemizygous nonsense mutation in cancer-testis antigen 55 (CT55) suffering from male infertility with extreme disruption in sperm production, morphology, and locomotion. Specifically, the insufficiency of sperm individualization, excessive residue of unnecessary cytoplasm, and defects in acrosome development were evident in the spermatozoa of the patients. Furthermore, mouse models with depletion of Ct55 showed accelerated infertility with age, mimicking the defects in sperm individualization, unnecessary cytoplasm removal, and meanwhile exhibiting the disrupted cumulus-oocyte complex penetration. Mechanistically, our functional experiments uncovered CT55 as a new autophagic manipulator to regulate spermatogenesis via selectively interacting with LAMP2 and GABARAP (which are key regulators in the autophagy process) and further fine-tuning their expression. Therefore, our findings revealed CT55 as a novel CTA gene involved in spermatogenesis due to its unprecedented autophagy activity.


Assuntos
Antígenos Nucleares , Infertilidade Masculina , Neoplasias , Animais , Humanos , Masculino , Camundongos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Neoplasias/metabolismo , Sêmen/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Antígenos Nucleares/metabolismo
16.
Cell Metab ; 35(1): 200-211.e9, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36309010

RESUMO

Despite its central importance in cellular metabolism, many details remain to be determined regarding subcellular lactate metabolism and its regulation in physiology and disease, as there is sensitive spatiotemporal resolution of lactate distribution, and dynamics remains a technical challenge. Here, we develop and characterize an ultrasensitive, highly responsive, ratiometric lactate sensor, named FiLa, enabling the monitoring of subtle lactate fluctuations in living cells and animals. Utilizing FiLa, we demonstrate that lactate is highly enriched in mammalian mitochondria and compile an atlas of subcellular lactate metabolism that reveals lactate as a key hub sensing various metabolic activities. In addition, FiLa sensors also enable direct imaging of elevated lactate levels in diabetic mice and facilitate the establishment of a simple, rapid, and sensitive lactate assay for point-of-care clinical screening. Thus, FiLa sensors provide powerful, broadly applicable tools for defining the spatiotemporal landscape of lactate metabolism in health and disease.


Assuntos
Diabetes Mellitus Experimental , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Mitocôndrias/metabolismo , Ácido Láctico/metabolismo , Mamíferos
17.
Dev Cell ; 13(2): 268-82, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17681137

RESUMO

Axin is a scaffold protein that controls multiple important pathways, including the canonical Wnt pathway and JNK signaling. Here we have identified an Axin-interacting protein, Aida, which blocks Axin-mediated JNK activation by disrupting Axin homodimerization. During investigation of in vivo functions of Axin/JNK signaling and aida in development, it was found that Axin, besides ventralizing activity by facilitating beta-catenin degradation, possesses a dorsalizing activity that is mediated by Axin-induced JNK activation. This dorsalizing activity is repressed when aida is overexpressed in zebrafish embryos. Whereas Aida-MO injection leads to dorsalized embryos, JNK-MO and MKK4-MO can ventralize embryos. The anti-dorsalization activity of aida is conferred by its ability to block Axin-mediated JNK activity. We further demonstrate that dorsoventral patterning regulated by Axin/JNK signaling is independent of maternal or zygotic Wnt signaling. We have thus identified a dorsalization pathway that is exerted by Axin/JNK signaling and its inhibitor Aida during vertebrate embryogenesis.


Assuntos
Padronização Corporal , Proteínas de Transporte/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Repressoras/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , beta Catenina/metabolismo , Animais , Proteína Axina , Padronização Corporal/efeitos dos fármacos , Células COS , Linhagem Celular , Chlorocebus aethiops , Dimerização , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia , Embrião não Mamífero/enzimologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Oligonucleotídeos Antissenso/farmacologia , Fenótipo , Ligação Proteica/efeitos dos fármacos , Proteínas Repressoras/química , Proteínas Wnt/metabolismo , Peixe-Zebra/metabolismo
18.
EMBO J ; 27(11): 1537-48, 2008 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-18480843

RESUMO

We previously showed that Cidea(-/-) mice are resistant to diet-induced obesity through the upregulation of energy expenditure. The AMP-activated protein kinase (AMPK), consisting of catalytic alpha subunit and regulatory subunits beta and gamma, has a pivotal function in energy homoeostasis. We show here that AMPK protein levels and enzymatic activity were significantly increased in the brown adipose tissue of Cidea(-/-) mice. We also found that Cidea is colocalized with AMPK in the endoplasmic reticulum and forms a complex with AMPK in vivo through specific interaction with the beta subunit of AMPK, but not with the alpha or gamma subunit. When co-expressed with Cidea, the stability of AMPK-beta subunit was dramatically reduced due to increased ubiquitination-mediated degradation, which depends on a physical interaction between Cidea and AMPK. Furthermore, AMPK stability and enzymatic activity were increased in Cidea(-/-) adipocytes differentiated from mouse embryonic fibroblasts or preadipocytes. Our data strongly suggest that AMPK can be regulated by Cidea-mediated ubiquitin-dependent proteosome degradation, and provide a molecular explanation for the increased energy expenditure and lean phenotype in Cidea-null mice.


Assuntos
Adipócitos/enzimologia , Tecido Adiposo Marrom/enzimologia , Proteínas Reguladoras de Apoptose/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ubiquitinação , Proteínas Quinases Ativadas por AMP , Tecido Adiposo Marrom/citologia , Animais , Proteínas Reguladoras de Apoptose/genética , Regulação para Baixo , Retículo Endoplasmático/enzimologia , Ativação Enzimática , Estabilidade Enzimática , Camundongos , Camundongos Knockout , Mutação , Subunidades Proteicas/metabolismo
19.
Biochem J ; 436(2): 437-45, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21426302

RESUMO

Muscle contraction requires high energy fluxes, which are supplied by MM-CK (muscle-type creatine kinase) which couples to the myofibril. However, little is known about the detailed molecular mechanisms of how MM-CK participates in and is regulated during muscle contraction. In the present study, MM-CK is found to physically interact with the slow skeletal muscle-type MyBPC1 (myosin-binding protein C1). The interaction between MyBPC1 and MM-CK depended on the creatine concentration in a dose-dependent manner, but not on ATP, ADP or phosphocreatine. The MyBPC1-CK interaction favoured acidic conditions, and the two molecules dissociated at above pH 7.5. Domain-mapping experiments indicated that MM-CK binds to the C-terminal domains of MyBPC1, which is also the binding site of myosin. The functional coupling of myosin, MyBPC1 and MM-CK is further corroborated using an ATPase activity assay in which ATP expenditure accelerates upon the association of the three proteins, and the apparent K(m) value of myosin is therefore reduced. The results of the present study suggest that MyBPC1 acts as an adaptor to connect the ATP consumer (myosin) and the regenerator (MM-CK) for efficient energy metabolism and homoeostasis.


Assuntos
Proteínas de Transporte/fisiologia , Creatina Quinase Forma MM/metabolismo , Fibras Musculares de Contração Lenta/fisiologia , Miosinas/metabolismo , Animais , Metabolismo Energético/fisiologia , Células HEK293 , Homeostase/fisiologia , Humanos , Camundongos , Fibras Musculares de Contração Lenta/enzimologia , Músculo Esquelético/citologia , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Ligação Proteica/fisiologia , Recrutamento Neurofisiológico/fisiologia
20.
J Mol Histol ; 53(1): 1-11, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34813022

RESUMO

Abdominal aortic aneurysm (AAA) has been associated with the dysfunction of vascular smooth muscle cells (VSMCs) and extracellular matrix (ECM) remodelling. Runt-related transcription factor 3 (RUNX3) has been reported to be up-regulated in aneurysmal aorta samples compared with normal aorta. However, its function in VSMCs and the mechanism of function remains unknown. Therefore, our study aimed to investigate the role of RUNX3 in ECM remodelling and VSMC function, and further explore the underlying mechanism. Our results verified that RUNX3 was increased in aortic samples of AAA compared with healthy controls. Overexpression vectors of RUNX3 (ov-RUNX3) and siRNA of RUNX3 (si-RUNX3) were transfected into Human aortic smooth muscle cells (HAoSMCs). The results indicated that ov-RUNX3 promoted cell proliferation, migration, and MMP-2/3/9 secretion, and suppressed TIMP-1, collagen I/III, SM22, MYH11 and CNN1 expression in HAoSMCs. The silencing of RUNX3 has the opposite effect. Furthermore, we found that RUNX3 targets TGF-ß1 and suppressed its transcription. The silencing of TGF-ß1 increased cell proliferation, migration and MMP-2/3/9 expression, and inhibited TIMP-1, Collagen I/III, SM22, MYH11 and CNN1 expression. In addition, TGF-ß1 reversed the effect of RUNX3 overexpression on HAoSMCs. Hence, our study indicated that RUNX3 promotes cell proliferation, migration, and ECM remodelling through suppressing TGF-ß1.


Assuntos
Aneurisma da Aorta Abdominal/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Músculo Liso Vascular/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima/fisiologia , Adulto , Idoso , Aorta/citologia , Aneurisma da Aorta Abdominal/metabolismo , Western Blotting , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasmídeos/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Transfecção
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