Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.030
Filtrar
1.
Adv Exp Med Biol ; 1152: 365-375, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456194

RESUMO

Massively parallel sequencing, genomic and proteomic technologies have provided near complete resolution of signaling landscape of breast cancer (BCa). NEDD4 family of E3-ubiquitin ligases comprises a large family of proteins particularly, SMURFs (SMURF1, SMURF2), WWPs and NEDD4 which are ideal candidates for targeted therapy. However, it is becoming progressively more understandable that SMURFs and NEDD4 have "split-personalities". These molecules behave dualistically in breast cancer and future studies must converge on detailed identification of context specific role of these proteins in BCa. Finally, we provide scattered clues of regulation of SMURF2 by oncogenic miRNAs, specifically considering longstanding questions related to regulation of SMURF1 and WWPs by miRNAs in BCa. SMURFS, WWPs and NEDD4 are versatile regulators and represent a fast-growing field in cancer research and better understanding of the underlying mechanisms will be helpful in transition of our knowledge from a segmented view to a more conceptual continuum.


Assuntos
Neoplasias da Mama/enzimologia , Ubiquitina-Proteína Ligases Nedd4/genética , Ubiquitina-Proteína Ligases/genética , Neoplasias da Mama/genética , Feminino , Humanos , MicroRNAs/genética , Oncogenes , Proteômica , Transdução de Sinais , Ubiquitinação
2.
DNA Cell Biol ; 38(10): 1030-1039, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31368785

RESUMO

Both endogenous and exogenous factors can cause DNA damage that compromises genomic integrity and cell viability. A proper DNA damage response (DDR) plays a role in maintaining genome stability and preventing tumorigenesis. DNA double-strand breaks (DSBs) are the most toxic DNA lesion, whose response is dominated by the ataxia-telangiectasia mutated (ATM) protein kinase. After being activated by the sensor Mre11-Rad50-Nbs1 (MRN) complex or acetyltransferase Tip60, ATM rapidly phosphorylates downstream targets to launch DDR signaling when DNA is damaged. However, the exact mechanism of DDR is complex and ambiguous. Ufmylation, one type of ubiquitin-like modification, proceeds mainly through a three-step enzymatic reaction to help ubiquitin-fold modifier 1 (Ufm1), attach to substrates with ubiquitin-like modifier-activating enzyme 5 (Uba5), Ufm1-conjugating enzyme 1 (Ufc1) and Ufm1-specific ligase 1 (Ufl1). Although ubiquitination is essential to the DSBs response, the potential function of ufmylation in DDR is largely unknown. Herein, we review the relationship between ufmylation and DDR to elucidate the function and mechanism of ufmylation in DDR, which would reveal the pathogenesis of some diseases and provide new guidance to create a therapeutic method.


Assuntos
Doenças Cardiovasculares/metabolismo , Quebras de DNA de Cadeia Dupla , Neoplasias/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas/metabolismo , Esquizofrenia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/patologia , Reparo do DNA , Genoma Humano , Instabilidade Genômica , Humanos , Neoplasias/genética , Neoplasias/patologia , Ligação Proteica , Proteínas/genética , Esquizofrenia/genética , Esquizofrenia/patologia , Transdução de Sinais , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
3.
Genes Dev ; 33(17-18): 1221-1235, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371437

RESUMO

TRIM71/LIN-41, a phylogenetically conserved regulator of development, controls stem cell fates. Mammalian TRIM71 exhibits both RNA-binding and protein ubiquitylation activities, but the functional contribution of either activity and relevant primary targets remain poorly understood. Here, we demonstrate that TRIM71 shapes the transcriptome of mouse embryonic stem cells (mESCs) predominantly through its RNA-binding activity. We reveal that TRIM71 binds targets through 3' untranslated region (UTR) hairpin motifs and that it acts predominantly by target degradation. TRIM71 mutations implicated in etiogenesis of human congenital hydrocephalus impair target silencing. We identify a set of primary targets consistently regulated in various human and mouse cell lines, including MBNL1 (Muscleblind-like protein 1). MBNL1 promotes cell differentiation through regulation of alternative splicing, and we demonstrate that TRIM71 promotes embryonic splicing patterns through MBNL1 repression. Hence, repression of MBNL1-dependent alternative splicing may contribute to TRIM71's function in regulating stem cell fates.


Assuntos
Processamento Alternativo/genética , Regulação da Expressão Gênica/genética , Proteínas de Ligação a RNA/genética , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Linhagem Celular Tumoral , Células-Tronco Embrionárias , Humanos , Camundongos , Camundongos Knockout , Mutação , Motivos de Nucleotídeos , Ligação Proteica , Domínios Proteicos/genética , Interferência de RNA , Proteínas de Ligação a RNA/metabolismo
4.
Gene ; 712: 143963, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31279706

RESUMO

BACKGROUND: The aim of this study was to identify the expression of LIM and calponin-homology domains 1 (LIMCH1) in lung cancer and normal tissues, to determine the interaction between LIMCH1 and HUWE1 in regulating p53 stability. METHODS: The expression of LIMCH1 was detected by the Oncomine and Cancer Genome Atlas databases. Expression of LIMCH1 mRNA was identified using qRT-PCR. In transfected human lung cancer cells, co-immunoprecipitation experiments were performed. The mechanism that HUWE1 sustained lung cancer malignancy was verified by western blotting. The proliferation of tranfected cells was assessed by CCK-8 assay and colony formation. RESULTS: Bioinformatic data and e TCGA database suggested LIMCH1 mRNA levels in tumor tissues were down-regulated compared to tumor adjacent tissues. We found low expression of LIMCH1 mRNA in tumor sites and tumor cell line. Exogenous expression of LIMCH1 interacts with HUWE1 promotes expression of p53. Use of siRNA or shRNA against LIMCH1 resulted in decreased p53 protein levels. LIMCH1 deletion lead to enhance of p53 ubiquitination and protein expression of p53 and substrate p21, puma. Growth curve showed that LIMCH1 deletion significantly promoted the proliferation of A549 cells. CONCLUSIONS: LIMCH1 was a negative regulator and indicated a new molecular mechanism for the pathogenesis of lung cancer via modulating HUWE1 and p53.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas com Domínio LIM/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Células A549 , Idoso , Linhagem Celular Tumoral , Proliferação de Células , Biologia Computacional , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Proteínas com Domínio LIM/genética , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Processamento de Proteína Pós-Traducional , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
5.
Nat Commun ; 10(1): 3020, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289263

RESUMO

Human cytomegalovirus (HCMV) can persistently infect humans, but how HCMV avoids humoral immunity is not clear. The neonatal Fc receptor (FcRn) controls IgG transport from the mother to the fetus and prolongs IgG half-life. Here we show that US11 inhibits the assembly of FcRn with ß2m and retains FcRn in the endoplasmic reticulum (ER), consequently blocking FcRn trafficking to the endosome. Furthermore, US11 recruits the ubiquitin enzymes Derlin-1, TMEM129 and UbE2J2 to engage FcRn, consequently initiating the dislocation of FcRn from the ER to the cytosol and facilitating its degradation. Importantly, US11 inhibits IgG-FcRn binding, resulting in a reduction of IgG transcytosis across intestinal or placental epithelial cells and IgG degradation in endothelial cells. Hence, these results identify the mechanism by which HCMV infection exploits an ER-associated degradation pathway through US11 to disable FcRn functions. These results have implications for vaccine development and immune surveillance.


Assuntos
Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Evasão da Resposta Imune , Imunidade Humoral , Proteínas de Ligação a RNA/metabolismo , Receptores Fc/metabolismo , Proteínas Virais/metabolismo , Linhagem Celular , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/virologia , Degradação Associada com o Retículo Endoplasmático/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutagênese Sítio-Dirigida , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/imunologia , Receptores Fc/imunologia , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Virais/genética , Proteínas Virais/imunologia
6.
Nature ; 571(7766): 565-569, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31316206

RESUMO

Parkinson's disease is a neurodegenerative disorder with motor symptoms linked to the loss of dopaminergic neurons in the substantia nigra compacta. Although the mechanisms that trigger the loss of dopaminergic neurons are unclear, mitochondrial dysfunction and inflammation are thought to have key roles1,2. An early-onset form of Parkinson's disease is associated with mutations in the PINK1 kinase and PRKN ubiquitin ligase genes3. PINK1 and Parkin (encoded by PRKN) are involved in the clearance of damaged mitochondria in cultured cells4, but recent evidence obtained using knockout and knockin mouse models have led to contradictory results regarding the contributions of PINK1 and Parkin to mitophagy in vivo5-8. It has previously been shown that PINK1 and Parkin have a key role in adaptive immunity by repressing presentation of mitochondrial antigens9, which suggests that autoimmune mechanisms participate in the aetiology of Parkinson's disease. Here we show that intestinal infection with Gram-negative bacteria in Pink1-/- mice engages mitochondrial antigen presentation and autoimmune mechanisms that elicit the establishment of cytotoxic mitochondria-specific CD8+ T cells in the periphery and in the brain. Notably, these mice show a sharp decrease in the density of dopaminergic axonal varicosities in the striatum and are affected by motor impairment that is reversed after treatment with L-DOPA. These data support the idea that PINK1 is a repressor of the immune system, and provide a pathophysiological model in which intestinal infection acts as a triggering event in Parkinson's disease, which highlights the relevance of the gut-brain axis in the disease10.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/fisiopatologia , Intestinos/microbiologia , Doença de Parkinson/genética , Doença de Parkinson/microbiologia , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Animais , Apresentação do Antígeno/imunologia , Autoantígenos/imunologia , Axônios/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Citrobacter rodentium/imunologia , Citrobacter rodentium/patogenicidade , Modelos Animais de Doenças , Neurônios Dopaminérgicos/imunologia , Neurônios Dopaminérgicos/patologia , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/patologia , Feminino , Intestinos/imunologia , Intestinos/patologia , Levodopa/uso terapêutico , Masculino , Camundongos , Mitocôndrias/imunologia , Mitocôndrias/patologia , Neostriado/imunologia , Neostriado/microbiologia , Neostriado/patologia , Neostriado/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Proteínas Quinases/imunologia , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia
7.
J Sci Food Agric ; 99(14): 6139-6154, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31152450

RESUMO

BACKGROUND: Tomato is an important food item and a cocktail of phytonutrients. In the current study, metabolites from a non-pathogenic fungal species Penicillium oxalicum have been exploited to obtain nutritionally augmented tomato fruits from the plants to better withstand against Alternaria alternata infection. RESULTS: Initially, bioactivity-guided assay and chromatographic analyses identified the bioactive metabolites of P. oxalicum [benzenedicarboxylic acid (BDA) and benzimidazole]. Then, ≥3 times elevated quantities of vitamins and other nutritional elements (protein, fat, fibers, and carbohydrates) were achieved by the foliar application of BDA. The maximum increase (625.81%) was recorded in riboflavin contents; however, thiamine showed the second highest enhancement (542.86%). Plant metabolites analysis revealed that jasmonic acid contents were boosted 121.53% to significantly enhance guaiacyl lignin defenses along with the reduction in coumarin contents. The protein profile analysis explored three most actively responding protein species toward BDA applications, (i) palmitoyltransferase protein Q9FLM3; (ii) serine/threonine-protein kinase O48814; and (iii) E3 ubiquitin-protein ligase Q9FJQ8. The O48814 improved plant defenses; whereas, Q9FJQ8 protein was negatively regulating cysteine-type endopeptidase activity and assisted plant to resist schedule alterations. Tomato cultivar with more active innate metabolism was found to be more responsive toward BDA. Furthermore, the bioactive compounds were enriched by using the two-step extraction method of ethyl acetate and chloroform, respectively. CONCLUSION: Penicillium oxalicum a non-pathogenic fungal species, produced BDA, induced nutritional contents in tomato and protected it against Alternaria alternata. The current study is the first report on the bioactivity of BDA and benzimidazole concerning the nutritional enhancement and plant defense improvement. © 2019 Society of Chemical Industry.


Assuntos
Alternaria/fisiologia , Ácidos Dicarboxílicos/farmacologia , Lycopersicon esculentum/microbiologia , Penicillium/metabolismo , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/genética , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/genética , Inoculantes Agrícolas/química , Inoculantes Agrícolas/metabolismo , Ácidos Dicarboxílicos/metabolismo , Frutas/química , Frutas/genética , Frutas/metabolismo , Frutas/microbiologia , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Valor Nutritivo , Penicillium/química , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
8.
Photochem Photobiol Sci ; 18(7): 1685-1699, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31166333

RESUMO

The UVR8 photoreceptor in Arabidopsis thaliana is specific for ultraviolet-B (UV-B; 280-315 nm) radiation and its activation leads to a number of UV-B acclimation responses, including the accumulation of flavonoids. UVR8 participates in a signaling cascade involving COP1 and HY5 so that the absence of any of these components results in a reduction in the ability of a plant to accumulate flavonoids in response to UV; Cop1 mutants show high dropouts and hy5-ks50 hyh double mutants show very low levels of flavonoids. The predominant phenolics in Arabidopsis thaliana are sinapic acid derivatives as well as non-aclyated quercetin and kaempferol di- and triglycosides containing glucose and rhamnose as glycosylated sugar moieties. How this flavonoid profile in Arabidopsis thaliana is affected by UV radiation, how rapidly these changes occur in changing UV conditions, and which components of the UV-B signalling pathway are involved in rapid UV acclimatization reactions is poorly understood. In the present study, we examined these questions by characterizing the flavonoid profiles of Arabidopsis thaliana signalling mutants and wild types grown under different UV levels of constant UV-B+PAR ratios and then transferring a subset of plants to alternate UV conditions. Results indicate that flavonoid accumulation in Arabidopsis thaliana is triggered by UV and this response is amplified by higher levels of UV but not by all compounds to the same extent. The catechol structure in quercetin seems to be less important than the glycosylation pattern, e.g. having 2 rhamnose moieties in determining responsivity. At low UV+PAR intensities the introduction of UV leads to an initial tendency of increase of flavonoids in the wild types that was detected after 3 days. It took 7 days for these changes to be detected in plants grown under high UV+PAR intensities suggesting a priming of PAR. Thus, the flavonoid profile in Arabidopsis thaliana is altered over time following exposure to UV and PAR, but the functional significance of these changes is currently unclear.


Assuntos
Arabidopsis/efeitos da radiação , Flavonoides/metabolismo , Transdução de Sinais/efeitos da radiação , Raios Ultravioleta , Arabidopsis/química , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Cromatografia Líquida de Alta Pressão , Proteínas Cromossômicas não Histona/metabolismo , Flavonoides/análise , Mutagênese , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
9.
Photochem Photobiol Sci ; 18(7): 1675-1684, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31218318

RESUMO

UV-B exposure of plants regulates expression of numerous genes concerned with various responses. Sudden exposure of non-acclimated plants to high fluence rate, short wavelength UV-B induces expression via stress-related signaling pathways that are not specific to the UV-B stimulus, whereas low fluence rates of UV-B can regulate expression via the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8). However, there is little information about whether non-stressful, low fluence rate UV-B treatments can activate gene expression independently of UVR8. Here, transcriptomic analysis of wild-type and uvr8 mutant Arabidopsis exposed to low fluence rate UV-B showed that numerous genes were regulated independently of UVR8. Moreover, nearly all of these genes were distinct to those induced by stress treatments. A small number of genes were expressed at all UV-B fluence rates employed and may be concerned with activation of eustress responses that facilitate acclimation to changing conditions. Expression of the gene encoding the transcription factor ARABIDOPSIS NAC DOMAIN CONTAINING PROTEIN 13 (ANAC13) was studied to characterise a low fluence rate, UVR8-independent response. ANAC13 is induced by as little as 0.1 µmol m-2 s-1 UV-B and its regulation is independent of components of the canonical UVR8 signaling pathway COP1 and HY5/HYH. Furthermore, UV-B induced expression of ANAC13 is independent of the photoreceptors CRY1, CRY2, PHOT1 and PHOT2 and phytochromes A, B, D and E. ANAC13 expression is induced over a range of UV-B wavelengths at low doses, with maximum response at 310 nm. This study provides a basis for further investigation of UVR8 and stress independent, low fluence rate UV-B signaling pathway(s).


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Raios Ultravioleta , Proteínas de Arabidopsis/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas Cromossômicas não Histona/genética , Criptocromos/genética , Criptocromos/metabolismo , Transdução de Sinais/efeitos da radiação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
10.
Nat Commun ; 10(1): 2426, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160578

RESUMO

DNA replication initiation is a two-step process. During the G1-phase of the cell cycle, the ORC complex, CDC6, CDT1, and MCM2-7 assemble at replication origins, forming pre-replicative complexes (pre-RCs). In S-phase, kinase activities allow fork establishment through (CDC45/MCM2-7/GINS) CMG-complex formation. However, only a subset of all potential origins becomes activated, through a poorly understood selection mechanism. Here we analyse the pre-RC proteomic interactome in human cells and find C13ORF7/RNF219 (hereafter called OBI1, for ORC-ubiquitin-ligase-1) associated with the ORC complex. OBI1 silencing result in defective origin firing, as shown by reduced CMG formation, without affecting pre-RC establishment. OBI1 catalyses the multi-mono-ubiquitylation of a subset of chromatin-bound ORC3 and ORC5 during S-phase. Importantly, expression of non-ubiquitylable ORC3/5 mutants impairs origin firing, demonstrating their relevance as OBI1 substrates for origin firing. Our results identify a ubiquitin signalling pathway involved in origin activation and provide a candidate protein for selecting the origins to be fired.


Assuntos
Replicação do DNA/fisiologia , Fase G1/fisiologia , Complexo de Reconhecimento de Origem/metabolismo , Origem de Replicação/fisiologia , Fase S/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Complexo de Reconhecimento de Origem/genética , Proteômica , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
11.
Plant Physiol Biochem ; 141: 343-352, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207495

RESUMO

Plant U-box (PUB) E3 ubiquitin ligases play crucial roles in the plant response to abiotic stress and the phytohormone abscisic acid (ABA) signaling, but little is known about them in bryophytes. Here, a representative U-box armadillo repeat (PUB-ARM) ubiquitin E3 ligase from Antarctic moss Pohlia nutans (PnSAG1), was explored for its role in abiotic stress response in Arabidopsis thaliana and Physcomitrella patens. The expression of PnSAG1 was rapidly induced by exogenous abscisic acid (ABA), salt, cold and drought stresses. PnSAG1 was localized to the cytoplasm and showed E3 ubiquitin ligase activity by in vitro ubiquitination assay. The PnSAG1-overexpressing Arabidopsis enhanced the sensitivity with respect to ABA and salt stress during seed germination and early root growth. Similarly, heterogeneous overexpression of PnSAG1 in P. patens was more sensitive to the salinity and ABA in their gametophyte growth. The analysis by RT-qPCR revealed that the expression of salt stress/ABA-related genes were downregulated in PnSAG1-overexpressing plants after salt treatment. Taken together, our results indicated that PnSAG1 plays a negative role in plant response to ABA and salt stress.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/fisiologia , Briófitas/enzimologia , Bryopsida/fisiologia , Estresse Salino , Ubiquitina-Proteína Ligases/genética , Regiões Antárticas , Arabidopsis/genética , Briófitas/genética , Bryopsida/genética , Biologia Computacional , Secas , Regulação da Expressão Gênica de Plantas , Células Germinativas Vegetais/metabolismo , Germinação , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/fisiologia , Transdução de Sinais
12.
Nat Commun ; 10(1): 2429, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160553

RESUMO

The WW domain-containing protein 2 (Wwp2) gene, the host gene of miR-140, codes for the Wwp2 protein, which is an HECT-type E3 ubiquitin ligases abundantly expressed in articular cartilage. However, its function remains unclear. Here, we show that mice lacking Wwp2 and mice in which the Wwp2 E3 enzyme is inactivated (Wwp2-C838A) exhibit aggravated spontaneous and surgically induced osteoarthritis (OA). Consistent with this phenotype, WWP2 expression level is downregulated in human OA cartilage. We also identify Runx2 as a Wwp2 substrate and Adamts5 as a target gene, as similar as miR-140. Analysis of Wwp2-C838A mice shows that loss of Wwp2 E3 ligase activity results in upregulation of Runx2-Adamts5 signaling in articular cartilage. Furthermore, in vitro transcribed Wwp2 mRNA injection into mouse joints reduces the severity of experimental OA. We propose that Wwp2 has a role in protecting cartilage from OA by suppressing Runx2-induced Adamts5 via Runx2 poly-ubiquitination and degradation.


Assuntos
Proteína ADAMTS5/metabolismo , Cartilagem Articular/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Osteoartrite/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Artrite Experimental/genética , Artrite Experimental/metabolismo , Cartilagem Articular/diagnóstico por imagem , Modelos Animais de Doenças , Humanos , Articulação do Joelho/diagnóstico por imagem , Meniscos Tibiais/cirurgia , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Osteoartrite/metabolismo , RNA Mensageiro/farmacologia , Transdução de Sinais , Crânio/diagnóstico por imagem , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Microtomografia por Raio-X , Adulto Jovem
13.
Med Oncol ; 36(8): 70, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203460

RESUMO

Alterations in BRCA2, PALB2, CHEK2, and p53 genes have been identified for their association with male breast cancer in various studies. The incidence of male breast cancer in India is consistent with its global rate. The present study was carried out with an aim to evaluate the genetic alterations in male breast cancer patients from Malwa region of Punjab, India. Four male breast cancer patients belonging to different families were recruited from Guru Gobind Singh Medical College and Hospital, Faridkot, India. A total of 51 genes reported with implications in the pathogenesis of breast cancer were screened using next generation sequencing. Germline variations were found in BRCA1, BRCA2, PMS2, p53, and PALB2 genes, previously reported to be associated with MBC as well as FBC. In addition to these, 13 novel missense alterations were detected in eight genes including STK11, FZR1, PALB2, BRCA2, NF2, BAP1, BARD1, and CHEK2. Impact of these missense alterations on structure and function of protein was also analyzed through molecular dynamics simulation. Structural analysis of these single nucleotide polymorphisms (SNPs) revealed significant impact on the encoded protein functioning.


Assuntos
Neoplasias da Mama Masculina/genética , Idoso , Proteína BRCA2/genética , Neoplasias da Mama Masculina/epidemiologia , Quinase do Ponto de Checagem 2/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Simulação de Dinâmica Molecular , Mutação , Linhagem , Polimorfismo de Nucleotídeo Único , Proteínas Serina-Treonina Quinases/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética
15.
Mol Plant Microbe Interact ; 32(11): 1487-1495, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31241412

RESUMO

Phytoplasmas are the causative agent of numerous diseases of plant species all over the world, including important food crops. The mode by which phytoplasmas multiply and behave in their host is poorly understood and often based on genomic data. We used yeast two-hybrid screening to find new protein-protein interactions between the causal agent of apple proliferation 'Candidatus Phytoplasma mali' and its host plant. Here, we report that the 'Ca. P. mali' strain PM19 genome encodes a protein PM19_00185 that interacts with at least six different ubiquitin-conjugating enzymes (UBC; E2) of Arabidopsis thaliana. An in vitro ubiquitination assay showed that PM19_00185 is enzymatically active as E3 ligase with A. thaliana E2 UBC09 and Malus domestica E2 UBC10. We show that a nonhost bacteria (Pseudomonas syringae pv. tabaci) can grow in transgenic A. thaliana plant lines expressing PM19_00185. A connection of phytoplasma effector proteins with the proteasome proteolytic pathway has been reported before. However, this is, to our knowledge, the first time that a phytoplasma effector protein with E3 ligase activity has been reported.


Assuntos
Phytoplasma , Doenças das Plantas , Ubiquitina-Proteína Ligases , Arabidopsis/enzimologia , Arabidopsis/parasitologia , Malus/parasitologia , Phytoplasma/enzimologia , Phytoplasma/genética , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/imunologia , Ubiquitina-Proteína Ligases/metabolismo
16.
Plast Reconstr Surg ; 144(1): 12-20, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31246791

RESUMO

BACKGROUND: Pathogenic mutations have been identified in approximately 10 percent of patients who present with breast cancer. Notably, failure to identify deleterious genetic mutations has particular implications for patients undergoing abdominally based breast reconstruction, as the donor site can be used only once. The authors sought to determine: (1) how many patients underwent genetic testing before unilateral abdominally based free flap breast reconstruction; (2) how often deleterious mutations were detected after abdominally based free flap breast reconstruction; and (3) the cost-effectiveness of expanding genetic testing in this patient population. METHODS: The authors retrospectively identified all patients who underwent unilateral abdominally based free flap breast reconstruction at Brigham and Women's Hospital/Dana-Farber Cancer Institute between 2007 and 2016. Chart review was performed to collect relevant demographic and clinical data. Relevant hospital financial data were obtained. RESULTS: Of the 713 who underwent free flap breast reconstruction, 160 patients met inclusion criteria, and mean follow-up was 5.8 years. Three patients (1.9 percent of 160) underwent contralateral surgery after completing reconstruction, two of whom had BRCA2 and one with ATM mutation. One hundred eleven patients met National Comprehensive Cancer Network guidelines for genetic testing, but of those only 55.9 percent (62 patients) were tested. Financial data revealed that testing every patient in the cohort would result in a net savings of $262,000. CONCLUSIONS: During a relatively short follow-up period, a small percentage of patients were diagnosed with pathogenic mutations and underwent contralateral mastectomy and reconstruction. However, because of the costliness of surgery and the decreased cost of genetic testing, it is cost-effective to test every patient before unilateral abdominally based free flap breast reconstruction.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Mutação/genética , Adulto , Idoso , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína BRCA2/genética , Neoplasias da Mama/cirurgia , Quinase do Ponto de Checagem 2/genética , Assistência à Saúde , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Feminino , Retalhos de Tecido Biológico/estatística & dados numéricos , Testes Genéticos , Humanos , Mamoplastia/métodos , Mastectomia/métodos , Pessoa de Meia-Idade , RNA Helicases/genética , Estudos Retrospectivos , Ubiquitina-Proteína Ligases/genética
17.
Nat Commun ; 10(1): 2572, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189917

RESUMO

Activation of G-protein coupled receptors elevates cAMP levels promoting dissociation of protein kinase A (PKA) holoenzymes and release of catalytic subunits (PKAc). This results in PKAc-mediated phosphorylation of compartmentalized substrates that control central aspects of cell physiology. The mechanism of PKAc activation and signaling have been largely characterized. However, the modes of PKAc inactivation by regulated proteolysis were unknown. Here, we identify a regulatory mechanism that precisely tunes PKAc stability and downstream signaling. Following agonist stimulation, the recruitment of the chaperone-bound E3 ligase CHIP promotes ubiquitylation and proteolysis of PKAc, thus attenuating cAMP signaling. Genetic inactivation of CHIP or pharmacological inhibition of HSP70 enhances PKAc signaling and sustains hippocampal long-term potentiation. Interestingly, primary fibroblasts from autosomal recessive spinocerebellar ataxia 16 (SCAR16) patients carrying germline inactivating mutations of CHIP show a dramatic dysregulation of PKA signaling. This suggests the existence of a negative feedback mechanism for restricting hormonally controlled PKA activities.


Assuntos
Subunidades Catalíticas da Proteína Quinase Dependente de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Retroalimentação Fisiológica/fisiologia , Chaperonas Moleculares/metabolismo , Ataxias Espinocerebelares/patologia , Animais , Retroalimentação Fisiológica/efeitos dos fármacos , Fibroblastos , Células HEK293 , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Hipocampo/patologia , Holoenzimas/metabolismo , Humanos , Leupeptinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Cultura Primária de Células , Ligação Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Nucleosídeos de Purina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Ataxias Espinocerebelares/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia
18.
Nat Commun ; 10(1): 2625, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201299

RESUMO

Enormous efforts have been made to target metabolic dependencies of cancer cells for developing new therapies. However, the therapeutic efficacy of glycolysis inhibitors is limited due to their inability to elicit cell death. Hexokinase 2 (HK2), via its mitochondrial localization, functions as a central nexus integrating glycolysis activation and apoptosis resilience. Here we identify that K63-linked ubiquitination by HectH9 regulates the mitochondrial localization and function of HK2. Through stable isotope tracer approach and functional metabolic analyses, we show that HectH9 deficiency impedes tumor glucose metabolism and growth by HK2 inhibition. The HectH9/HK2 pathway regulates cancer stem cell (CSC) expansion and CSC-associated chemoresistance. Histological analyses show that HectH9 expression is upregulated and correlated with disease progression in prostate cancer. This work uncovers that HectH9 is a novel regulator of HK2 and cancer metabolism. Targeting HectH9 represents an effective strategy to achieve long-term tumor remission by concomitantly disrupting glycolysis and inducing apoptosis.


Assuntos
Hexoquinase/metabolismo , Células-Tronco Neoplásicas/fisiologia , Neoplasias da Próstata/patologia , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Feminino , Glicólise , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Nus , Próstata/patologia , RNA Interferente Pequeno , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
19.
BMC Cancer ; 19(1): 422, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060523

RESUMO

BACKGROUND: Ovarian carcinomas presenting homologous recombination deficiency (HRD), which is observed in about 50% of cases, are more sensitive to platinum and PARP inhibitor therapies. Although platinum resistant disease has a low chance to be responsive to platinum-based chemotherapy, a set of patients is retreated with platinum and some of them are responsive. In this study, we evaluated copy number alterations, HR gene mutations and HR deficiency scores in ovarian cancer patients with prolonged platinum sensitivity. METHODS: In this retrospective study (2005 to 2014), we selected 31 patients with platinum resistant ovarian cancer retreated with platinum therapy. Copy number alterations and HR scores were evaluated using the OncoScan® FFPE platform in 15 cases. The mutational profile of 24 genes was investigated by targeted-NGS. RESULTS: The median values of the four HRD scores were higher in responders (LOH = 15, LST = 28, tAI = 33, CS = 84) compared with non-responders (LOH = 7.5, LST = 17.5, tAI = 23, CS = 47). Patients with high LOH, LST, tAI and CS scores had better response rates, although these differences were not statistically significant. Response rate to platinum retreatment was 22% in patients with CCNE1 gains and 83.5% in patients with no CCNE1 gains (p = 0.041). Furthermore, response rate was 54.5% in patients with RB1 loss and 25% in patients without RB1 loss (p = 0.569). Patients with CCNE1 gains showed a worse progression free survival (PFS = 11.1 months vs 3.7 months; p = 0.008) and a shorter overall survival (OS = 39.3 months vs 7.1 months; p = 0.007) in comparison with patients with no CCNE1 gains. Patients with RB1 loss had better PFS (9.0 months vs 2.6 months; p = 0.093) and OS (27.4 months vs 3.6 months; p = 0.025) compared with cases with no RB1 loss. Four tumor samples were BRCA mutated and tumor mutations were not associated with response to treatment. CONCLUSIONS: HR deficiency was found in 60% of our cases and HRD medium values were higher in responders than in non-responders. Despite the small number of patients tested, CCNE1 gain and RB1 loss discriminate patients with tumors extremely sensitive to platinum retreatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ciclina E/genética , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Oncogênicas/genética , Neoplasias Ovarianas/genética , Compostos de Platina/farmacologia , Proteínas de Ligação a Retinoblastoma/genética , Ubiquitina-Proteína Ligases/genética , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Brasil/epidemiologia , Pré-Escolar , Variações do Número de Cópias de DNA/genética , Análise Mutacional de DNA , Feminino , Recombinação Homóloga/genética , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/mortalidade , Compostos de Platina/uso terapêutico , Intervalo Livre de Progressão , Retratamento , Estudos Retrospectivos , Análise de Sobrevida
20.
Plant Cell Physiol ; 60(8): 1804-1810, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31119298

RESUMO

While ligand-induced autophosphorylation of receptor-like kinases (RLKs) is known to be critical for triggering the downstream responses, biochemical mechanism by which each phosphorylation site contributes to the initiation of corresponding signaling cascades is only poorly understood, except the involvement of some phosphorylation sites in the regulation of catalytic activity of these RLKs. In this article, we first confirmed that the phosphorylation of S493 of AtCERK1 is involved in the regulation of chitin-induced defense responses by the complementation of an atcerk1 mutant with AtCERK1(S493A) cDNA. In vitro kinase assay with the heterologously expressed kinase domain of AtCERK1, GST-AtCERK1cyt, showed that the S493A mutation did not affect the autophosphorylation of AtCERK1 itself but diminished the transphosphorylation of downstream signaling components, PBL27 and PUB4. On the other hand, a phosphomimetic mutant, GST-AtCERK1(S493D)cyt, transphosphorylated these substrates as similar to the wild type AtCERK1. These results suggested that the phosphorylation of S493 does not contribute to the regulation of catalytic activity but plays an important role for the transphosphorylation of the downstream signaling components, thus contributing to the initiation of chitin signaling. To our knowledge, it is a novel finding that a specific phosphorylation site contributes to the regulation of transphosphorylation activity of RLKs. Further studies on the structural basis by which S493 phosphorylation contributes to the regulation of transphosphorylation would contribute to the understanding how the ligand-induced autophosphorylation of RLKs properly regulates the downstream signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Quitina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Fosforilação/genética , Fosforilação/fisiologia , Imunidade Vegetal/genética , Imunidade Vegetal/fisiologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA