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1.
Cell Rep ; 37(5): 109939, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34731627

RESUMO

Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder, causing defects of social interaction and repetitive behaviors. Here, we identify a de novo heterozygous gene-truncating mutation of the Sentrin-specific peptidase1 (SENP1) gene in people with ASD without neurodevelopmental delay. We find that Senp1+/- mice exhibit core autistic-like symptoms such as social deficits and repetitive behaviors but normal learning and memory ability. Moreover, we find that inhibitory and excitatory synaptic functions are severely affected in the retrosplenial agranular (RSA) cortex of Senp1+/- mice. Lack of Senp1 leads to increased SUMOylation and degradation of fragile X mental retardation protein (FMRP), also implicated in syndromic ASD. Importantly, re-introducing SENP1 or FMRP specifically in RSA fully rescues the defects of synaptic function and autistic-like symptoms of Senp1+/- mice. Together, these results demonstrate that disruption of the SENP1-FMRP regulatory axis in the RSA causes autistic symptoms, providing a candidate region for ASD pathophysiology.

2.
Nanomaterials (Basel) ; 11(11)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34835792

RESUMO

Formic acid (FA) is found to be a potential candidate for the storage of hydrogen. For dehydrogenation of FA, the supports of our catalysts were acquired by conducting ZnCl2 treatment and carbonation for biomass waste. The texture and surface properties significantly affected the size and dispersion of Pd and its interaction with the support so as to cause the superior catalytic performance of catalysts. Microporous carbon obtained by carbonization of ZnCl2 activated peanut shells (CPS-ZnCl2) possessing surface areas of 629 m2·g-1 and a micropore rate of 73.5%. For ZnCl2 activated melon seed (CMS-ZnCl2), the surface area and micropore rate increased to 1081 m2·g-1 and 80.0%, respectively. In addition, the introduction of ZnCl2 also caused the increase in surface O content and reduced the acidity of the catalyst. The results represented that CMS-ZnCl2 with uniform honeycomb morphology displayed the best properties, and the as-prepared Pd/CMS-ZnCl2 catalyst afforded 100% hydrogen selectivity as well as excellent catalytic activity with an initial high turnover number (TON) value of 28.3 at 30 °C and 100.1 at 60 °C.

4.
Nat Commun ; 12(1): 5764, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599187

RESUMO

Regulatory T (Treg) cells are one of the major immunosuppressive cell types in cancer and a potential target for immunotherapy, but targeting tumor-infiltrating (TI) Treg cells has been challenging. Here, using single-cell RNA sequencing of immune cells from renal clear cell carcinoma (ccRCC) patients, we identify two distinct transcriptional fates for TI Treg cells, Fate-1 and Fate-2. The Fate-1 signature is associated with a poorer prognosis in ccRCC and several other solid cancers. CD177, a cell surface protein normally expressed on neutrophil, is specifically expressed on Fate-1 TI Treg cells in several solid cancer types, but not on other TI or peripheral Treg cells. Mechanistically, blocking CD177 reduces the suppressive activity of Treg cells in vitro, while Treg-specific deletion of Cd177 leads to decreased tumor growth and reduced TI Treg frequency in mice. Our results thus uncover a functional CD177+ TI Treg population that may serve as a target for TI Treg-specific immunotherapy.


Assuntos
Proteínas Ligadas por GPI/metabolismo , Homeostase , Isoantígenos/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Receptores de Superfície Celular/metabolismo , Linfócitos T Reguladores/metabolismo , Animais , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/patologia , Proteínas Ligadas por GPI/deficiência , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Camundongos Knockout , Prognóstico , Receptores de Superfície Celular/deficiência , Análise de Célula Única , Transcrição Genética
5.
Blood ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34624089

RESUMO

Although oncogenicity of the stem cell regulator SOX9 has been implicated in many solid tumors, its role in lymphomagenesis remains largely unknown. In this study, we showed that SOX9 is overexpressed preferentially in a subset of diffuse large B-cell lymphomas (DLBCL) harboring IGH-BCL2 translocations. SOX9 positivity in DLBCL correlates with advanced stage of disease. Silencing of SOX9 decreased cell proliferation, induced G1/S arrest and increased apoptosis of DLBCL cells, both in vitro and in vivo. Whole transcriptome analysis and CHIP-seq assays identified DHCR24, a terminal enzyme in cholesterol biosynthesis, as a direct target of SOX9, which promotes cholesterol synthesis by increasing DHCR24 expression. Enforced expression of DHCR24 was capable of rescuing the phenotypes associated with SOX9 knockdown in DLBCL cells. In DLBCL cell line xenograft models, SOX9 knockdown resulted in lower DHCR24 level, reduced cholesterol content and decreased tumor load. Pharmacological inhibition of cholesterol synthesis also inhibited DLBCL xenograft tumorigenesis, the reduction of which is more pronounced in DLBCL cell line with higher SOX9 expression, suggesting that it may be addicted to cholesterol. In summary, our study demonstrates that SOX9 can drive lymphomagenesis through DHCR24 and the cholesterol biosynthesis pathway. This SOX9-DHCR24-cholesterol biosynthesis axis may serve as a novel treatment target for DLBCL.

6.
Nat Chem Biol ; 17(12): 1314-1323, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34608293

RESUMO

Spindle position control is essential for cell fate determination and organogenesis. Early studies indicate the essential role of the evolutionarily conserved Gαi/LGN/NuMA network in spindle positioning. However, the regulatory mechanisms that couple astral microtubules dynamics to the spindle orientation remain elusive. Here we delineated a new mitosis-specific crotonylation-regulated astral microtubule-EB1-NuMA interaction in mitosis. EB1 is a substrate of TIP60, and TIP60-dependent crotonylation of EB1 tunes accurate spindle positioning in mitosis. Mechanistically, TIP60 crotonylation of EB1 at Lys66 forms a dynamic link between accurate attachment of astral microtubules to the lateral cell cortex defined by NuMA-LGN and fine tune of spindle positioning. Real-time imaging of chromosome movements in HeLa cells expressing genetically encoded crotonylated EB1 revealed the importance of crotonylation dynamics for accurate control of spindle orientation during metaphase-anaphase transition. These findings delineate a general signaling cascade that integrates protein crotonylation with accurate spindle positioning for chromosome stability in mitosis.

7.
Cell Death Differ ; 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465891

RESUMO

Neurogenesis plays a critical role in brain physiology and behavioral performance, and defective neurogenesis leads to neurological and psychiatric disorders. Here, we show that PLCß4 expression is markedly reduced in SENP2-deficient cells and mice, resulting in decreased IP3 formation and altered intracellular calcium homeostasis. PLCß4 stability is regulated by the SUMO-dependent ubiquitin-mediated proteolytic pathway, which is catalyzed by PIAS2α and RNF4. SUMOylated PLCß4 is transported to the nucleus through Nup205- and RanBP2-dependent pathways and regulates nuclear signaling. Furthermore, dysregulated calcium homeostasis induced defects in neurogenesis and neuronal viability in SENP2-deficient mice. Finally, SENP2 and PLCß4 are stimulated by starvation and oxidative stress, which maintain calcium homeostasis regulated neurogenesis. Our findings provide mechanistic insight into the critical roles of SENP2 in the regulation of PLCß4 SUMOylation, and the involvement of SENP2-PLCß4 axis in calcium homeostasis regulated neurogenesis under stress.

8.
Nat Commun ; 12(1): 5416, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518544

RESUMO

Hypoxia is the most prominent feature in human solid tumors and induces activation of hypoxia-inducible factors and their downstream genes to promote cancer progression. However, whether and how hypoxia regulates overall mRNA homeostasis is unclear. Here we show that hypoxia inhibits global-mRNA decay in cancer cells. Mechanistically, hypoxia induces the interaction of AGO2 with LUBAC, the linear ubiquitin chain assembly complex, which co-localizes with miRNA-induced silencing complex and in turn catalyzes AGO2 occurring Met1-linked linear ubiquitination (M1-Ubi). A series of biochemical experiments reveal that M1-Ubi of AGO2 restrains miRNA-mediated gene silencing. Moreover, combination analyses of the AGO2-associated mRNA transcriptome by RIP-Seq and the mRNA transcriptome by RNA-Seq confirm that AGO2 M1-Ubi interferes miRNA-targeted mRNA recruiting to AGO2, and thereby facilitates accumulation of global mRNAs. By this mechanism, short-term hypoxia may protect overall mRNAs and enhances stress tolerance, whereas long-term hypoxia in tumor cells results in seriously changing the entire gene expression profile to drive cell malignant evolution.


Assuntos
Proteínas Argonauta/genética , Regulação Neoplásica da Expressão Gênica , Homeostase/genética , Metionina/genética , RNA Mensageiro/genética , Ubiquitinação , Células A549 , Proteínas Argonauta/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Inativação Gênica , Células HEK293 , Células HeLa , Humanos , Hipóxia , Metionina/metabolismo , MicroRNAs/genética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Células PC-3 , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo
10.
Nat Commun ; 12(1): 4371, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272364

RESUMO

Metabolic programming and mitochondrial dynamics along with T cell differentiation affect T cell fate and memory development; however, how to control metabolic reprogramming and mitochondrial dynamics in T cell memory development is unclear. Here, we provide evidence that the SUMO protease SENP1 promotes T cell memory development via Sirt3 deSUMOylation. SENP1-Sirt3 signalling augments the deacetylase activity of Sirt3, promoting both OXPHOS and mitochondrial fusion. Mechanistically, SENP1 activates Sirt3 deacetylase activity in T cell mitochondria, leading to reduction of the acetylation of mitochondrial metalloprotease YME1L1. Consequently, deacetylation of YME1L1 suppresses its activity on OPA1 cleavage to facilitate mitochondrial fusion, which results in T cell survival and promotes T cell memory development. We also show that the glycolytic intermediate fructose-1,6-bisphosphate (FBP) as a negative regulator suppresses AMPK-mediated activation of the SENP1-Sirt3 axis and reduces memory development. Moreover, glucose limitation reduces FBP production and activates AMPK during T cell memory development. These data show that glucose limitation activates AMPK and the subsequent SENP1-Sirt3 signalling for T cell memory development.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Linfócitos T CD8-Positivos/imunologia , Cisteína Endopeptidases/metabolismo , Memória Imunológica , Mitocôndrias/metabolismo , Sirtuína 3/metabolismo , Linfócitos T/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Acetilação , Aloenxertos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Neoplasias do Colo/imunologia , Frutosedifosfatos/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Glucose/deficiência , Memória Imunológica/genética , Metabolômica , Metaloendopeptidases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Mitocôndrias/genética , Mitocôndrias/ultraestrutura , Dinâmica Mitocondrial/genética , Proteínas Mitocondriais/metabolismo , Fosforilação Oxidativa , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/genética , Sumoilação , Linfócitos T/imunologia
11.
Hepatology ; 74(4): 1864-1883, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33934381

RESUMO

BACKGROUND AND AIMS: NAFLD, characterized by aberrant triglyceride accumulation in liver, affects the metabolic remodeling of hepatic and nonhepatic tissues by secreting altered hepatokines. Small ubiquitin-related modifier (SUMO)-specific protease 2 (SENP2) is responsible for de-SUMOylation of target protein, with broad effects on cell growth, signal transduction, and developmental processes. However, the role of SENP2 in hepatic metabolism remains unclear. APPROACH AND RESULTS: We found that SENP2 was the most dramatically increased SENP in the fatty liver and that its level was modulated by fed/fasted conditions. To define the role of hepatic SENP2 in metabolic regulation, we generated liver-specific SENP2 knockout (Senp2-LKO) mice. Senp2-LKO mice exhibited resistance to high-fat diet-induced hepatic steatosis and obesity. RNA-sequencing analysis showed that Senp2 deficiency up-regulated genes involved in fatty acid oxidation and down-regulated genes in lipogenesis in the liver. Additionally, ablation of hepatic SENP2 activated thermogenesis of adipose tissues. Improved energy homeostasis of both the liver and adipose tissues by SENP2 disruption prompted us to detect the hepatokines, with FGF21 identified as a key factor markedly elevated in Senp2-LKO mice that maintained metabolic homeostasis. Loss of FGF21 obviously reversed the positive effects of SENP2 deficiency on metabolism. Mechanistically, by screening transcriptional factors of FGF21, peroxisome proliferator-activated receptor alpha (PPARα) was defined as the mediator for SENP2 and FGF21. SENP2 interacted with PPARα and deSUMOylated it, thereby promoting ubiquitylation and subsequent degradation of PPARα, which in turn inhibited FGF21 expression and fatty acid oxidation. Consistently, SENP2 overexpression in liver facilitated development of metabolic disorders. CONCLUSIONS: Our finding demonstrated a key role of hepatic SENP2 in governing metabolic balance by regulating liver-adipose tissue crosstalk, linking the SUMOylation process to metabolic regulation.

12.
Theranostics ; 11(8): 3981-3995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33664876

RESUMO

Salmonella typhimurium (S. typhimurium) infection of macrophage induces NLRC4 inflammasome-mediated production of the pro-inflammatory cytokines IL-1ß. Post-translational modifications on NLRC4 are critical for its activation. Sirtuin3 (SIRT3) is the most thoroughly studied mitochondrial nicotinamide adenine dinucleotide (NAD+) -dependent deacetylase. We wondered whether SIRT3 mediated-deacetylation could take part in NLRC4 inflammasome activation. Methods: We initially tested IL-1ß production and pyroptosis after cytosolic transfection of flagellin or S. typhimurium infection in wild type and SIRT3-deficient primary peritoneal macrophages via immunoblotting and ELISA assay. These results were confirmed in SIRT3-deficient immortalized bone marrow derived macrophages (iBMDMs) which were generated by CRISPR-Cas9 technology. In addition, in vivo experiments were conducted to confirm the role of SIRT3 in S. typhimurium-induced cytokines production. Then NLRC4 assembly was analyzed by immune-fluorescence assay and ASC oligomerization assay. Immunoblotting, ELISA and flow cytometry were performed to clarify the role of SIRT3 in NLRP3 and AIM2 inflammasomes activation. To further investigate the mechanism of SIRT3 in NLRC4 activation, co-immunoprecipitation (Co-IP), we did immunoblot, cellular fractionation and in-vitro deacetylation assay. Finally, to clarify the acetylation sites of NLRC4, we performed liquid chromatography-mass spectrometry (LC-MS) and immunoblotting analysis. Results: SIRT3 deficiency led to significantly impaired NLRC4 inflammasome activation and pyroptosis both in vitro and in vivo. Furthermore, SIRT3 promotes NLRC4 inflammasome assembly by inducing more ASC speck formation and ASC oligomerization. However, SIRT3 is dispensable for NLRP3 and AIM2 inflammasome activation. Moreover, SIRT3 interacts with and deacetylates NLRC4 to promote its activation. Finally, we proved that deacetylation of NLRC4 at Lys71 or Lys272 could promote its activation. Conclusions: Our study reveals that SIRT3 mediated-deacetylation of NLRC4 is pivotal for NLRC4 activation and the acetylation switch of NLRC4 may aid the clearance of S. typhimurium infection.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Inflamassomos/metabolismo , Sirtuína 3/metabolismo , Acetilação , Sequência de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Sítios de Ligação/genética , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Citocinas/biossíntese , Feminino , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Inflamassomos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Knockout , Medicina de Precisão , Salmonella typhimurium/imunologia , Salmonella typhimurium/patogenicidade , Sirtuína 3/deficiência , Sirtuína 3/genética
13.
Nat Commun ; 12(1): 1812, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753739

RESUMO

Human hexokinase 2 is an essential regulator of glycolysis that couples metabolic and proliferative activities in cancer cells. The binding of hexokinase 2 to the outer membrane of mitochondria is critical for its oncogenic activity. However, the regulation of hexokinase 2 binding to mitochondria remains unclear. Here, we report that SUMOylation regulates the binding of hexokinase 2 to mitochondria. We find that hexokinase 2 can be SUMOylated at K315 and K492. SUMO-specific protease SENP1 mediates the de-SUMOylation of hexokinase 2. SUMO-defective hexokinase 2 preferably binds to mitochondria and enhances both glucose consumption and lactate production and decreases mitochondrial respiration in parallel. This metabolic reprogramming supports prostate cancer cell proliferation and protects cells from chemotherapy-induced cell apoptosis. Moreover, we demonstrate an inverse relationship between SENP1-hexokinase 2 axis and chemotherapy response in prostate cancer samples. Our data provide evidence for a previously uncovered posttranslational modification of hexokinase 2 in cancer cells, suggesting a potentially actionable strategy for preventing chemotherapy resistance in prostate cancer.


Assuntos
Carcinogênese/metabolismo , Hexoquinase/metabolismo , Mitocôndrias/metabolismo , Neoplasias da Próstata/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Docetaxel/farmacologia , Hexoquinase/genética , Humanos , Masculino , Camundongos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ligação Proteica , Sumoilação , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
Nature ; 592(7855): 606-610, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33658717

RESUMO

Intestinal stromal cells are known to modulate the propagation and differentiation of intestinal stem cells1,2. However, the precise cellular and molecular mechanisms by which this diverse stromal cell population maintains tissue homeostasis and repair are poorly understood. Here we describe a subset of intestinal stromal cells, named MAP3K2-regulated intestinal stromal cells (MRISCs), and show that they are the primary cellular source of the WNT agonist R-spondin 1 following intestinal injury in mice. MRISCs, which are epigenetically and transcriptomically distinct from subsets of intestinal stromal cells that have previously been reported3-6, are strategically localized at the bases of colon crypts, and function to maintain LGR5+ intestinal stem cells and protect against acute intestinal damage through enhanced R-spondin 1 production. Mechanistically, this MAP3K2 specific function is mediated by a previously unknown reactive oxygen species (ROS)-MAP3K2-ERK5-KLF2 axis to enhance production of R-spondin 1. Our results identify MRISCs as a key component of an intestinal stem cell niche that specifically depends on MAP3K2 to augment WNT signalling for the regeneration of damaged intestine.

15.
J Mol Cell Biol ; 13(2): 91-103, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33394042

RESUMO

Microtubules (MTs) are regulated by a number of known posttranslational modifications (PTMs) on α/ß-tubulin to fulfill diverse cellular functions. Here, we showed that SUMOylation is a novel PTM on α-tubulin in vivo and in vitro. The SUMOylation on α-tubulin mainly occurred at Lys 96 (K96), K166, and K304 of soluble α-tubulin and could be removed by small ubiquitin-related modifier (SUMO)-specific peptidase 1. In vitro experiments showed that tubulin SUMOylation could reduce interprotofilament interaction, promote MT catastrophe, and impede MT polymerization. In cells, mutation of the SUMOylation sites on α-tubulin reduced catastrophe frequency and increased the proportion of polymerized α-tubulin, while upregulation of SUMOylation with fusion of SUMO1 reduced α-tubulin assembly into MTs. Additionally, overexpression of SUMOylation-deficient α-tubulin attenuated the neurite extension in Neuro-2a cells. Thus, SUMOylation on α-tubulin represents a new player in the regulation of MT properties.

16.
Oxid Med Cell Longev ; 2020: 6240125, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299528

RESUMO

Nuclear factor erythroid 2-related factor 2 (NRF2) is a crucial transcription factor for cell adaptation and defense against oxidative stress. NRF2 activation confers Kras/Lkb1/Keap1 (KLK) mutant tumor cells with greater resistance to oxidative insults. We previously reported that SUMOylation at lysine residue 110 is important for the ability of NRF2 to promote reactive oxygen species (ROS) clearance in hepatocellular carcinoma. In this study, we investigated whether SUMOylation is necessary for the ability of NRF2 to inhibit KLK lung adenocarcinoma (LUAD) cell migration and invasion. Our experiments showed that mild oxidative stress reduced NRF2 SUMOylation, which promoted KLK LUAD cell migration and invasion. Mechanistically, NRF2 SUMOylation increased the antioxidant ability of NRF2 and reduced cellular ROS levels, mainly by transcriptionally activating Cat in KLK LUAD cells. With reduced NRF2 SUMOylation, increased ROS acted as signaling molecules to activate the JNK/c-Jun axis, which enhanced cell mobility and cell adhesion, to promote LUAD cell migration and invasion. Taken together, the results of this study reveal a novel signaling process in which reduced NRF2 SUMOylation permits increased KLK LUAD cell migration and invasion under mild oxidative stress.


Assuntos
Movimento Celular/fisiologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Sumoilação/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Antioxidantes/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/genética , Espécies Reativas de Oxigênio/metabolismo , Sumoilação/efeitos dos fármacos
17.
Cell Rep ; 33(1): 108191, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33027667

RESUMO

Despite the important roles of protein kinase Cε (PKCε) and transient receptor potential vanilloind 1 (TRPV1) in inflammatory hypersensitivity, how PKCε is involved in the regulation of thermal hyperalgesia is not fully understood. We report here that PKCε is SUMOylated at a C-terminal lysine residue (K534), which enhances the sensitivity of the TRPV1 channel. We demonstrate that PKCε phosphorylation promotes its SUMOylation, which in turn regulates the phosphorylation level of TRPV1 serine 800 residue via controlling the binding of PKCε and TRPV1 and increased PKCε kinase activity. More importantly, the reduced ability of PKCε knockdown mice to develop inflammatory thermal hyperalgesia was rescued by viral infection of lumbar 4/5 dorsal root ganglia neurons of wild-type PKCε, but not the SUMOylation-deficient PKCε mutant. Therefore, the SUMOylation of PKCε potentiates inflammatory thermal hyperalgesia through stabilizing the interaction with TRPV1 to enhance its function by phosphorylation.


Assuntos
Inflamação/genética , Dor/genética , Proteína Quinase C-épsilon/metabolismo , Animais , Camundongos , Nociceptividade , Transdução de Sinais , Sumoilação
18.
Biochem Biophys Res Commun ; 532(4): 591-597, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32900482

RESUMO

Mitochondria play a central role in biological oxidation that inevitably generates reactive oxygen species (ROS) as by-products. Maintenance of mitochondrial redox balance status requires NADPH, which is primarily generated by the mitochondrial matrix protein isocitrate dehydrogenase 2 (IDH2). The activity of IDH2 is regulated by post-translational modifications (PTMs). In this study, we found IDH2 is modified by small ubiquitin-like modifier 1 (SUMO1) at lysine 45. SUMO specific protease 1 (SENP1) is responsible for deSUMOylation of IDH2. SUMOylation of IDH2 is induced by oxidants and enhances the antioxidant activity of IDH2 to protect cells against oxidative stress. Mutation of the SUMOylation site impairs the enzymatic activity of IDH2 and hence decreases levels of α-ketoglutarate (α-KG), NADPH and GSH. Cells with SUMOylation deficient IDH2 suffer more apoptosis than that with wild type IDH2 under oxidative stress. These results indicate that SUMOylation is an important way to regulate IDH2 activity to maintain mitochondrial redox balance.


Assuntos
Isocitrato Desidrogenase/metabolismo , Estresse Oxidativo , Sumoilação , Animais , Linhagem Celular , Sobrevivência Celular , Ativação Enzimática , Humanos , Isocitrato Desidrogenase/química , Lisina/metabolismo , Camundongos
19.
Int J Mol Sci ; 21(16)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781782

RESUMO

Mitochondrial stress is considered as a factor that reprograms the mitochondrial biogenesis and metabolism. As known, SUMOylation occurs through a series of stress-induced biochemical reactions. During the process of SUMOylation, the small ubiquitin-like modifier (SUMO) and its specific proteases (SENPs) are key signal molecules. Furthermore, they are considered as novel mitochondrial stress sensors that respond to the signals produced by various stresses. The responses are critical for mitochondrial homeostasis. The scope of this review is to provide an overview of the function of SUMOylation in the mitochondrial stress response, to delineate a SUMOylation-involved signal network diagram, and to highlight a number of key questions that remain answered.


Assuntos
Mitocôndrias/metabolismo , Estresse Fisiológico , Sumoilação , Animais , Restrição Calórica , Humanos , Biogênese de Organelas , Resposta a Proteínas não Dobradas
20.
Cell Death Differ ; 27(11): 3146-3161, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32483381

RESUMO

Posttranslational modifications of nuclear proteins, including transcription factors, nuclear receptors, and their coregulators, have attracted much attention in cancer research. Although phosphorylation of oligodendrocyte transcription factor 2 (Olig2) may contribute to the notorious resistance of gliomas to radiation and genotoxic drugs, the precise mechanisms remain elusive. We show here that in addition to phosphorylation, Olig2 is also conjugated by small ubiquitin-like modifier-1 (SUMO1) at three lysine residues K27, K76, and K112. SUMOylation is required for Olig2 to suppress p53-mediated cell cycle arrest and apoptosis induced by genotoxic damage, and to enhance resistance to temozolomide (TMZ) in glioma. Both SUMOylation and triple serine motif (TSM) phosphorylation of Olig2 are required for the antiapoptotic function. Olig2 SUMOylation enhances its genetic targeting ability, which in turn occludes p53 recruitment to Cdkn1a promoter for DNA-damage responses. Our work uncovers a SUMOylation-dependent regulatory mechanism of Olig2 in regulating cancer survival.

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