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1.
J Cell Biol ; 219(2)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31985747

RESUMO

IRE1ß is an ER stress sensor uniquely expressed in epithelial cells lining mucosal surfaces. Here, we show that intestinal epithelial cells expressing IRE1ß have an attenuated unfolded protein response to ER stress. When modeled in HEK293 cells and with purified protein, IRE1ß diminishes expression and inhibits signaling by the closely related stress sensor IRE1α. IRE1ß can assemble with and inhibit IRE1α to suppress stress-induced XBP1 splicing, a key mediator of the unfolded protein response. In comparison to IRE1α, IRE1ß has relatively weak XBP1 splicing activity, largely explained by a nonconserved amino acid in the kinase domain active site that impairs its phosphorylation and restricts oligomerization. This enables IRE1ß to act as a dominant-negative suppressor of IRE1α and affect how barrier epithelial cells manage the response to stress at the host-environment interface.


Assuntos
Retículo Endoplasmático/metabolismo , Endorribonucleases/metabolismo , Endorribonucleases/fisiologia , Proteínas de Membrana/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Células CACO-2 , Endorribonucleases/genética , Células HEK293 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Moleculares , Proteínas Serina-Treonina Quinases/genética , Proteostase , Análise de Sequência de Proteína , Transdução de Sinais , Estresse Fisiológico , Resposta a Proteínas não Dobradas
2.
Toxicol Lett ; 324: 20-29, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31987890

RESUMO

Similar to other types of neuronal degeneration, Parkinson's disease (PD) is characterized by the aggregation of a pathological protein, α-synuclein. The endoplasmic reticulum (ER) is the principal site of protein synthesis, quality control and degradation. Genetic mutants, environmental insults and other factors disturb ER balance and induce the accumulation of misfolded/unfolded proteins, which initiate ER stress and disturb normal cell function. ER stress perturbs Ca2+ homeostasis and initiates the activation of autophagy and inflammasomes, which have been identified as risk factors for the development of PD. However, the mechanisms by which ER stress contributes to the processed of PD pathogenesis and development remain unclear. This review summarizes current knowledge of ER stress and highlights the principal role of ER stress in PD pathogenesis which may help reveal novel sight to illustrate the pathomechanism of PD.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Doença de Parkinson/etiologia , Fator 6 Ativador da Transcrição/fisiologia , Adaptação Fisiológica , Animais , Autofagia , Cálcio/metabolismo , Endorribonucleases/fisiologia , Humanos , Doença de Parkinson/fisiopatologia , Proteínas Serina-Treonina Quinases/fisiologia , Resposta a Proteínas não Dobradas , Proteína 1 de Ligação a X-Box/fisiologia , eIF-2 Quinase/fisiologia
3.
DNA Cell Biol ; 39(2): 159-166, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31821009

RESUMO

Hippo signaling regulates the balance between cell proliferation and apoptosis to control the size of organs during development. Appropriate Hippo signaling is associated with stem cell differentiation, and inappropriate signaling can result in tumorigenesis and cancer. Hippo signaling activity is influenced not only by biochemical signals but also by mechanical force and the cytoskeleton transmitted through cell-cell junctions and cell-matrix adhesions. In this review, we describe the evidence for the regulation of Hippo signaling by the spatial reorganization of signaling components, mechanical force, and the cytoskeleton. Although our understanding of the relationship between Hippo signal transduction and mechanical force and the cytoskeleton is developing rapidly, many unresolved questions remain.


Assuntos
Citoesqueleto/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Fenômenos Biomecânicos/fisiologia , Carcinogênese/metabolismo , Diferenciação Celular , Proliferação de Células , Humanos , Microtúbulos/metabolismo , Transdução de Sinais/fisiologia
4.
Invest Ophthalmol Vis Sci ; 60(12): 3854-3862, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31529118

RESUMO

Purpose: Subconjunctival injection of antagomir-21 attenuates the progression of corneal neovascularization. We examined the underlying mechanism by investigating the regulation of microRNA (miR)-21 expression and the involvement of miR-21 in the homeostasis of corneal epithelial cells. Methods: Corneal epithelial cells were cultured with TGF-ß1 and/or under hypoxia conditions. miR-21 expression was measured by quantitative PCR. The direct targets of miR-21 were validated by the 3'-UTR luciferase reporter assay. Alterations of proangiogenic signaling and the epithelial-mesenchymal transition (EMT) phenotype after miR-21/Sprouty2 (SPRY2) knockdown were examined by Western blotting. The effect of conditioned medium on angiogenesis was assessed using the tube formation assay. Wound healing was evaluated by the migration and scratch assays. Results: TGF-ß1 or hypoxia upregulated miR-21, and miR-21 silencing abolished TGF-ß1/hypoxia-induced hypoxia inducible factor (HIF)-1α and VEGF expression. miR-21 inhibited SPRY2 by directly targeting its 3'-UTR. Simultaneous silencing of miR-21 and SPRY2 significantly upregulated p-ERK, HIF-1α, and VEGF and promoted angiogenesis. Induction of miR-21 or inhibition of SPRY2 reduced the levels of cytokeratin (CK)-3 and CK-12 and promoted EMT. Transwell and wound healing assays indicated that miR-21 promoted cell migration. Conclusions: TGF-ß1 or hypoxia induced miR-21 and inhibited SPRY2, thereby enhancing proangiogenic signaling, suppressing the epithelial phenotype, and promoting wound healing in corneal epithelial cells.


Assuntos
Epitélio Anterior/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas de Membrana/fisiologia , MicroRNAs/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/fisiologia , Animais , Western Blotting , Movimento Celular/fisiologia , Células Epiteliais/citologia , Transição Epitelial-Mesenquimal , Epitélio Anterior/efeitos dos fármacos , Hipóxia/metabolismo , Queratina-12/metabolismo , Queratina-3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Fator de Crescimento Transformador beta1/farmacologia
5.
Neuron ; 103(3): 380-394, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31394063

RESUMO

The Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) was touted as a memory molecule, even before its involvement in long-term potentiation (LTP) was shown. The enzyme has not disappointed, with subsequent demonstrations of remarkable structural and regulatory properties. Its neuronal functions now extend to long-term depression (LTD), and last year saw the first direct evidence for memory storage by CaMKII. Although CaMKII may have taken the spotlight, it is a member of a large family of diverse and interesting CaM kinases. Our aim is to place CaMKII in context of the other CaM kinases and then review certain aspects of this kinase that are of current interest.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Sequência de Aminoácidos , Animais , Encéfalo/enzimologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Cognição/fisiologia , Humanos , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Modelos Moleculares , Família Multigênica , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/fisiologia , Fosforilação , Conformação Proteica , Domínios Proteicos , Mapeamento de Interação de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/classificação , Proteínas Serina-Treonina Quinases/fisiologia , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica
6.
Molecules ; 24(17)2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31450667

RESUMO

In recent years, secreted peptides have been recognized as essential mediators of intercellular communication which governs plant growth, development, environmental interactions, and other mediated biological responses, such as stem cell homeostasis, cell proliferation, wound healing, hormone sensation, immune defense, and symbiosis, among others. Many of the known secreted peptide ligand receptors belong to the leucine-rich repeat receptor kinase (LRR-RK) family of membrane integral receptors, which contain more than 200 members within Arabidopsis making it the largest family of plant receptor kinases (RKs). Genetic and biochemical studies have provided valuable data regarding peptide ligands and LRR-RKs, however, visualization of ligand/LRR-RK complex structures at the atomic level is vital to understand the functions of LRR-RKs and their mediated biological processes. The structures of many plant LRR-RK receptors in complex with corresponding ligands have been solved by X-ray crystallography, revealing new mechanisms of ligand-induced receptor kinase activation. In this review, we briefly elaborate the peptide ligands, and aim to detail the structures and mechanisms of LRR-RK activation as induced by secreted peptide ligands within plants.


Assuntos
Leucina , Proteínas de Plantas/fisiologia , Domínios e Motivos de Interação entre Proteínas , Proteínas Serina-Treonina Quinases/fisiologia , Leucina/química , Ligantes , Modelos Moleculares , Peptídeos/química , Peptídeos/genética , Peptídeos/metabolismo , Reguladores de Crescimento de Planta , Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/química , Plantas/genética , Plantas/metabolismo , Ligação Proteica , Conformação Proteica , Proteínas Serina-Treonina Quinases/química , Transdução de Sinais , Relação Estrutura-Atividade
7.
Biol Pharm Bull ; 42(7): 1089-1097, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257285

RESUMO

Thio-dimethylarsinic acid (thio-DMA) was detected in human urine after exposure to inorganic arsenic and arsenosugars consumed by marine algae. Our previous studies have shown that thio-DMA disturbed the cell cycle progression and arrested cells in mitosis, though the biological significance or the mechanism by which thio-DMA-induced mitotic phase accumulation occurs is yet to be understood. In this study, we showed that thio-DMA promotes the phosphorylation of BubR1 protein, which is one of the constituents of the spindle assembly checkpoint (SAC) complex and accumulates in the cell in mitotic phase. Binding of Mad2 to CDC20, also known as the marker of the mitotic checkpoint complex (MCC) formation during the activation of SAC, was enhanced and mitotic associated cell death by apoptosis was promoted in HeLa cells but not in HepG2 cells. Basal BubR1 protein level in HepG2 was 10-times lower than that of HeLa cells. Consequently, BubR1 knockdown HeLa cells were generated by small interfering RNA (siRNA) technique. The MCC formation and mitotic arrest induced by thio-DMA were completely inhibited in BubR1 knockdown cells. Moreover, BubR1 knockdown cells could survive in the medium containing higher concentrations of thio-DMA with some abnormalities such as larger cell size, huge nucleus, multiple nuclei, and abnormal DNA contents. Especially, cyclin B1 negative tetraploid cells, which signify interphase cells with tetraploid, increased and survived after 48-72 h treatment with thio-DMA. Thus, these results suggest that BubR1-mediated SAC activation and MCC formation are one of the defense systems for preventing the accumulation and survival of abnormal cells induced by thio-DMA.


Assuntos
Arsenicais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Mitose/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/fisiologia , Morte Celular/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , RNA Interferente Pequeno/genética
8.
Oncogene ; 38(38): 6479-6490, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31324890

RESUMO

Diffuse intrinsic pontine glioma (or DIPG) are pediatric high-grade gliomas associated with a dismal prognosis. They harbor specific substitution in histone H3 at position K27 that induces major epigenetic dysregulations. Most clinical trials failed so far to increase survival, and radiotherapy remains the most efficient treatment, despite only transient tumor control. We conducted the first lentiviral shRNA dropout screen in newly diagnosed DIPG to generate a cancer-lethal signature as a basis for the development of specific treatments with increased efficacy and reduced side effects compared to existing anticancer therapies. The analysis uncovered 41 DIPG essential genes among the 672 genes of human kinases tested, for which several distinct interfering RNAs impaired cell expansion of three different DIPG stem-cell cultures without deleterious effect on two control neural stem cells. Among them, PLK1, AURKB, CHEK1, EGFR, and GSK3A were previously identified by similar approach in adult GBM indicating common dependencies of these cancer cells and pediatric gliomas. As expected, we observed an enrichment of genes involved in proliferation and cell death processes with a significant number of candidates belonging to PTEN/PI3K/AKT and EGFR pathways already under scrutiny in clinical trials in this disease. We highlighted VRK3, a gene involved especially in cell cycle regulation, DNA repair, and neuronal differentiation, as a non-oncogenic addiction in DIPG. Its repression totally blocked DIPG cell growth in the four cellular models evaluated, and induced cell death in H3.3-K27M cells specifically but not in H3.1-K27M cells, supporting VRK3 as an interesting and promising target in DIPG.


Assuntos
Neoplasias do Tronco Encefálico/genética , Fosfotransferases/genética , Proteínas Serina-Treonina Quinases/fisiologia , RNA Interferente Pequeno/fisiologia , Análise de Sequência de RNA/métodos , Neoplasias do Tronco Encefálico/diagnóstico , Neoplasias do Tronco Encefálico/patologia , Sobrevivência Celular/genética , Células Cultivadas , /patologia , Genes Essenciais , Células HEK293 , Humanos , Fosfatidilinositol 3-Quinases/análise , Fosfatidilinositol 3-Quinases/genética , Fosfotransferases/análise , Prognóstico , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/genética , RNA Interferente Pequeno/análise
9.
Oncogene ; 38(38): 6537-6549, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31358902

RESUMO

Endometrial cancer (EC) is one of the most common gynecologic malignancies. However, the molecular mechanisms underlying the development and progression of EC remain unclear. Here, we demonstrated that the protein proviral insertion in murine lymphomas 2 (PIM2) was necessary for maintaining EC tumorigenesis in vivo and in vitro, and could inhibit AMPKα1 kinase activity in EC cells. Specifically, we found that PIM2 bound to AMPKα1, and directly phosphorylated it on Thr467. Phosphorylation of AMPKα1 by PIM2 led to decreasing AMPKα1 kinase activity, which in turn promoted aerobic glycolysis and tumor growth. In addition, PIM2 expression positively correlated with AMPKα1 Thr467 phosphorylation in EC tissues. Further, treatment with a combination of the PIM2 inhibitor SMI-4a and the AMPKα1 activator AICAR could effectively inhibit tumor growth. Thus, our findings provide insight into the role of PIM2 and AMPKα1 in EC and suggest that combination targeting of these proteins may represent a new strategy for EC treatment.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Neoplasias do Endométrio , Glicólise/genética , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Quinases Ativadas por AMP/genética , Adulto , Idoso , Animais , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Fosforilação/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
10.
Cell Mol Life Sci ; 76(19): 3827-3841, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302748

RESUMO

The Tousled-like kinases (TLKs) are an evolutionarily conserved family of serine-threonine kinases that have been implicated in DNA replication, DNA repair, transcription, chromatin structure, viral latency, cell cycle checkpoint control and chromosomal stability in various organisms. The functions of the TLKs appear to depend largely on their ability to regulate the H3/H4 histone chaperone ASF1, although numerous TLK substrates have been proposed. Over the last few years, a clearer picture of TLK function has emerged through the identification of new partners, the definition of specific roles in development and the elucidation of their structural and biochemical properties. In addition, the TLKs have been clearly linked to human disease; both TLK1 and TLK2 are frequently amplified in human cancers and TLK2 mutations have been identified in patients with neurodevelopmental disorders characterized by intellectual disability (ID), autism spectrum disorder (ASD) and microcephaly. A better understanding of the substrates, regulation and diverse roles of the TLKs is needed to understand their functions in neurodevelopment and determine if they are viable targets for cancer therapy. In this review, we will summarize current knowledge of TLK biology and its potential implications in development and disease.


Assuntos
Instabilidade Genômica , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Epigênese Genética , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Transtornos do Neurodesenvolvimento/genética , Domínios Proteicos , Proteínas Quinases/química , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/fisiologia
11.
Biol Pharm Bull ; 42(9): 1605-1607, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31243195

RESUMO

Recently, we demonstrated that Rac1 upregulation is involved in augmented bronchial smooth muscle (BSM) contractions of antigen-challenged mice. However, change in G protein-coupled receptor (GPCR)-induced Rac1 activation remains unknown in BSMs of repeatedly antigen-challenged (Chal.) mice. We here examined carbachol (CCh)-induced Rac1 activation in BSMs of Chal. mice. Gene expression levels of both Rac1 and Rac-guanine nucleotide exchange factors (GEFs), such as Tiam1 and Trio, were increased in BSMs of Chal. mice. Furthermore, CCh-induced Rac1 activation was inhibited by pretreatment with Rac1-GEF inhibitor NSC23766 and Rac1 inhibitor EHT1864 in BSMs of sensitized-control (S.C.) and Chal. mice. Compared with S.C. mice, CCh-induced Rac1 activation was increased in BSMs of Chal. mice. In conclusion, we reported that increased CCh-induced Rac1 activation via Tiam1 and Trio upregulation, in addition to upregulate Rac1, may be involved in increased CCh-induced BSM contractions in Chal. mice.


Assuntos
Brônquios/fisiologia , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Neuropeptídeos/fisiologia , Fosfoproteínas/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/fisiologia , Proteínas rac1 de Ligação ao GTP/fisiologia , Aminoquinolinas/farmacologia , Animais , Antígenos , Asma/genética , Asma/fisiopatologia , Brônquios/efeitos dos fármacos , Carbacol , Fatores de Troca do Nucleotídeo Guanina/genética , Masculino , Camundongos Endogâmicos BALB C , Agonistas Muscarínicos , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Neuropeptídeos/antagonistas & inibidores , Neuropeptídeos/genética , Ovalbumina , Fosfoproteínas/genética , Proteínas Serina-Treonina Quinases/genética , Pirimidinas/farmacologia , Pironas/farmacologia , Quinolinas/farmacologia , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/genética , Regulação para Cima , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Proteínas rac1 de Ligação ao GTP/genética
12.
Arterioscler Thromb Vasc Biol ; 39(8): 1645-1651, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31167564

RESUMO

OBJECTIVE: MARK4 (microtubule affinity-regulating kinase 4) regulates NLRP3 (nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain containing 3) inflammasome activation. The aim of the study is to examine the role of MARK4 in hematopoietic cells during atherosclerosis. METHODS AND RESULTS: We show increased MARK4 expression in human atherosclerotic lesions compared with adjacent areas. MARK4 is coexpressed with NLRP3, and they colocalize in areas enriched in CD68-positive but α-SMA (α-smooth muscle actin)-negative cells. Expression of MARK4 and NLRP3 in the atherosclerotic lesions is associated with the production of active IL (interleukin)-1ß and IL-18. To directly assess the role of hematopoietic MARK4 in NLRP3 inflammasome activation and atherosclerotic plaque formation, Ldlr (low-density lipoprotein receptor)-deficient mice were lethally irradiated and reconstituted with either wild-type or Mark4-deficient bone marrow cells, and were subsequently fed a high-fat diet and cholesterol diet for 9 weeks. Mark4 deficiency in bone marrow cells led to a significant reduction of lesion size, together with decreased circulating levels of IL-18 and IFN-γ (interferon-γ). Furthermore, Mark4 deficiency in primary murine bone marrow-derived macrophages prevented cholesterol crystal-induced NLRP3 inflammasome activation, as revealed by reduced caspase-1 activity together with reduced production of IL-1ß and IL-18. CONCLUSIONS: MARK4-dependent NLRP3 inflammasome activation in the hematopoietic cells regulates the development of atherosclerosis.


Assuntos
Aterosclerose/etiologia , Inflamassomos/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Humanos , Interleucina-18/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Receptores de LDL/fisiologia
13.
Infect Immun ; 87(8)2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31085703

RESUMO

Clostridium difficile is the leading cause of antibiotic-associated diarrhea in adults. During infection, C. difficile must detect the host environment and induce an appropriate survival strategy. Signal transduction networks involving serine/threonine kinases (STKs) play key roles in adaptation, as they regulate numerous physiological processes. PrkC of C. difficile is an STK with two PASTA domains. We showed that PrkC is membrane associated and is found at the septum. We observed that deletion of prkC affects cell morphology with an increase in mean size, cell length heterogeneity, and presence of abnormal septa. A ΔprkC mutant was able to sporulate and germinate but was less motile and formed more biofilm than the wild-type strain. Moreover, a ΔprkC mutant was more sensitive to antimicrobial compounds that target the cell envelope, such as the secondary bile salt deoxycholate, cephalosporins, cationic antimicrobial peptides, and lysozyme. This increased susceptibility was not associated with differences in peptidoglycan or polysaccharide II composition. However, the ΔprkC mutant had less peptidoglycan and released more polysaccharide II into the supernatant. A proteomic analysis showed that the majority of C. difficile proteins associated with the cell wall were less abundant in the ΔprkC mutant than the wild-type strain. Finally, in a hamster model of infection, the ΔprkC mutant had a colonization delay that did not significantly affect overall virulence.


Assuntos
Proteínas de Bactérias/fisiologia , Clostridium difficile/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Parede Celular/metabolismo , Clostridium difficile/metabolismo , Clostridium difficile/patogenicidade , Cricetinae , Farmacorresistência Bacteriana , Homeostase , Mesocricetus , Testes de Sensibilidade Microbiana , Peptidoglicano/metabolismo , Proteínas Serina-Treonina Quinases/genética , Virulência
14.
Dev Cell ; 49(4): 526-541.e5, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31031198

RESUMO

Meiosis produces gametes through a specialized, two-step cell division, which is highly error prone in humans. Reductional meiosis I, where maternal and paternal chromosomes (homologs) segregate, is followed by equational meiosis II, where sister chromatids separate. Uniquely during meiosis I, sister kinetochores are monooriented and pericentromeric cohesin is protected. Here, we demonstrate that these key adaptations for reductional chromosome segregation are achieved through separable control of multiple kinases by the meiosis-I-specific budding yeast Spo13 protein. Recruitment of Polo kinase to kinetochores directs monoorientation, while independently, cohesin protection is achieved by containing the effects of cohesin kinases. Therefore, reductional chromosome segregation, the defining feature of meiosis, is established by multifaceted kinase control by a master regulator. The recent identification of Spo13 orthologs, fission yeast Moa1 and mouse MEIKIN, suggests that kinase coordination by a meiosis I regulator may be a general feature in the establishment of reductional chromosome segregation.


Assuntos
Segregação de Cromossomos/fisiologia , Cinetocoros/fisiologia , Meiose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Centrômero/metabolismo , Cromátides/fisiologia , Proteínas Cromossômicas não Histona/metabolismo , Segregação de Cromossomos/genética , Cinetocoros/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/fisiologia
15.
Nat Plants ; 5(4): 414-423, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30936437

RESUMO

Lateral root (LR) emergence is a highly coordinated process involving precise cell-cell communication. Here, we show that MITOGEN-ACTIVATED PROTEIN KINASE3 (MPK3) and MPK6, and their upstream MAP-kinase kinases (MAPKKs), MKK4 and MKK5, function downstream of HAESA (HAE)/HAESA-LIKE2 (HSL2) and their ligand INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) during LR emergence. Loss of function of MKK4/MKK5 or MPK3/MPK6 results in restricted passage of the growing lateral root primordia (LRP) through the overlaying endodermal, cortical and epidermal cell layers, leading to reduced LR density. The MKK4/MKK5-MPK3/MPK6 module regulates the expression of cell wall remodelling genes in cells overlaying LRP and therefore controls pectin degradation in the middle lamella. Expression of constitutively active MKK4 or MKK5 driven by the HAE or HSL2 promoter fully rescues the LR emergence defect in the ida and hae hsl2 mutants. In addition, the MKK4/MKK5-MPK3/MPK6 module is indispensable in auxin-facilitated LR emergence. Our study provides insights into the auxin-governed and IDA-HAE/HLS2 ligand-receptor pair-mediated LR emergence process.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Sistema de Sinalização das MAP Quinases , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Raízes de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia
16.
Oncogene ; 38(27): 5541-5550, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30936457

RESUMO

The oncogene yes-associated protein (YAP) is a key modifier of liver homeostasis and regulates mitosis in hepatocytes as well as in malignantly transformed cells. However, the question of how YAP supports cell proliferation in hepatocellular carcinoma (HCC) is not well understood. Here we identified U2AF momology motif kinase 1 (UHMK1) as a direct transcriptional target of YAP and the transcription factor forkhead box M1 (FOXM1), which supports HCC cell proliferation but not migration. Indeed, UHMK1 stimulates the expression of genes that are specific for cell cycle regulation and which are known downstream effectors of YAP. By using BioID labeling and mass spectrometry, the dimerization partner, RB-like, E2F and multi-vulval class B (DREAM) complex constituent MYB proto-oncogene like 2 (MYBL2, B-MYB) was identified as a direct UHMK1 interaction partner. Like YAP, UHMK1 stimulates nuclear enrichment of MYBL2, which is associated HCC cell proliferation and the expression of the cell cycle regulators CCNB1, CCNB2, KIF20A, and MAD2L1. The association between YAP, UHMK1, MYBL2, and proliferation was confirmed in YAPS127A-transgenic mice and human HCC tissues. In summary, we provide a model by which YAP supports cell proliferation through the induction of important cell cycle regulators in a UHMK1- and MYBL2-dependent manner.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/fisiologia , Ciclo Celular/fisiologia , Replicação do DNA/fisiologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neoplasias Hepáticas/metabolismo , Ligação Proteica , Proteínas Serina-Treonina Quinases/fisiologia
17.
Nat Commun ; 10(1): 1547, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948712

RESUMO

The Hippo pathway maintains tissue homeostasis by negatively regulating the oncogenic transcriptional co-activators YAP and TAZ. Though functional inactivation of the Hippo pathway is common in tumors, mutations in core pathway components are rare. Thus, understanding how tumor cells inactivate Hippo signaling remains a key unresolved question. Here, we identify the kinase STK25 as an activator of Hippo signaling. We demonstrate that loss of STK25 promotes YAP/TAZ activation and enhanced cellular proliferation, even under normally growth-suppressive conditions both in vitro and in vivo. Notably, STK25 activates LATS by promoting LATS activation loop phosphorylation independent of a preceding phosphorylation event at the hydrophobic motif, which represents a form of Hippo activation distinct from other kinase activators of LATS. STK25 is significantly focally deleted across a wide spectrum of human cancers, suggesting STK25 loss may represent a common mechanism by which tumor cells functionally impair the Hippo tumor suppressor pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Linhagem Celular , Proliferação de Células , Genes Supressores de Tumor , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais
18.
Cell ; 177(2): 299-314.e16, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30929899

RESUMO

Autophagy is required in diverse paradigms of lifespan extension, leading to the prevailing notion that autophagy is beneficial for longevity. However, why autophagy is harmful in certain contexts remains unexplained. Here, we show that mitochondrial permeability defines the impact of autophagy on aging. Elevated autophagy unexpectedly shortens lifespan in C. elegans lacking serum/glucocorticoid regulated kinase-1 (sgk-1) because of increased mitochondrial permeability. In sgk-1 mutants, reducing levels of autophagy or mitochondrial permeability transition pore (mPTP) opening restores normal lifespan. Remarkably, low mitochondrial permeability is required across all paradigms examined of autophagy-dependent lifespan extension. Genetically induced mPTP opening blocks autophagy-dependent lifespan extension resulting from caloric restriction or loss of germline stem cells. Mitochondrial permeability similarly transforms autophagy into a destructive force in mammals, as liver-specific Sgk knockout mice demonstrate marked enhancement of hepatocyte autophagy, mPTP opening, and death with ischemia/reperfusion injury. Targeting mitochondrial permeability may maximize benefits of autophagy in aging.


Assuntos
Envelhecimento/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/fisiologia , Membranas Mitocondriais/fisiologia , Animais , Autofagia/fisiologia , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/fisiologia , Restrição Calórica , Células HEK293 , Humanos , Longevidade/fisiologia , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Permeabilidade , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais
19.
Sheng Li Xue Bao ; 71(2): 279-286, 2019 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-31008487

RESUMO

The aim of this study was to investigate the role of S100 calcium binding protein A16 (S100A16) in lipid metabolism in hepatocytes and its possible biological mechanism. HepG2 cells (human hepatoma cell line) were cultured with fatty acid to establish fatty acid culture model. The control model was cultured without fatty acid. Each model was divided into three groups and transfected with S100a16 over-expression, shRNA and vector plasmids, respectively. The concentration of triglyceride (TG) in the cells was measured by kit, and the lipid droplets was observed by oil red O staining. Immunoprecipitation and mass spectrometry were used to find the interesting proteins interacting with S100A16, and the interaction was verified by immunoprecipitation. The further mechanism was studied by Western blot and qRT-PCR. The results showed that the intracellular lipid droplet and TG concentrations in the fatty acid culture model were significantly higher than those in the control model. The accumulation of intracellular fat in the S100a16 over-expression group was significantly higher than that in the vector plasmid transfection group. There was an interaction between heat shock protein A5 (HSPA5) and S100A16. Over-expression of S100A16 up-regulated protein expression levels of HSPA5, inositol-requiring enzyme 1α (IRE1α) and pIREα1, which belong to endoplasmic reticulum stress HSPA5/IRE1α-XBP1 pathway. Meanwhile, over-expression of S100A16 up-regulated the mRNA expression levels of adipose synthesis-related gene Srebp1c, Acc and Fas. In the S100a16 shRNA plasmid transfection group, the above-mentioned protein and mRNA levels were lower than those of vector plasmid transfection group. These results suggest that S100A16 may promote lipid synthesis in HepG2 cells through endoplasmic reticulum stress HSPA5/IRE1α-XBP1 pathway.


Assuntos
Estresse do Retículo Endoplasmático , Metabolismo dos Lipídeos , Proteínas S100/fisiologia , Endorribonucleases/fisiologia , Proteínas de Choque Térmico/fisiologia , Células Hep G2 , Humanos , Proteínas Serina-Treonina Quinases/fisiologia , Triglicerídeos/biossíntese , Proteína 1 de Ligação a X-Box/fisiologia
20.
Cells ; 8(4)2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018586

RESUMO

Despite recent efforts, prostate cancer (PCa) remains one of the most common cancers in men. Currently, there is no effective treatment for castration-resistant prostate cancer (CRPC). There is, therefore, an urgent need to identify new therapeutic targets. The Hippo pathway and its downstream effectors-the transcriptional co-activators, Yes-associated protein (YAP) and its paralog, transcriptional co-activator with PDZ-binding motif (TAZ)-are foremost regulators of stem cells and cancer biology. Defective Hippo pathway signaling and YAP/TAZ hyperactivation are common across various cancers. Here, we draw on insights learned from other types of cancers and review the latest advances linking the Hippo pathway and YAP/TAZ to PCa onset and progression. We examine the regulatory interaction between Hippo-YAP/TAZ and the androgen receptor (AR), as main regulators of PCa development, and how uncontrolled expression of YAP/TAZ drives castration resistance by inducing cellular stemness. Finally, we survey the potential therapeutic targeting of the Hippo pathway and YAP/TAZ to overcome PCa.


Assuntos
Neoplasias da Próstata/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Fosfoproteínas , Neoplasias da Próstata/fisiopatologia , Transdução de Sinais , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
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