RESUMO
SH2 domain containing tyrosine phosphatase 2 (Shp2; PTPN11) regulates several intracellular pathways downstream of multiple growth factor receptors. Our studies implicate that Shp2 interacts with Caveolin-1 (Cav-1) protein in retinal ganglion cells (RGCs) and negatively regulates BDNF/TrkB signaling. This study aimed to investigate the mechanisms underlying the protective effects of shp2 silencing in the RGCs in glaucomatous conditions. Methods: Shp2 was silenced in the Cav-1 deficient mice and the age matched wildtype littermates using adeno-associated viral (AAV) constructs. Shp2 expression modulation was performed in an acute and a chronic mouse model of experimental glaucoma. AAV2 expressing Shp2 eGFP-shRNA under a strong synthetic CAG promoter was administered intravitreally in the animals' eyes. The contralateral eye received AAV-eGFP-scramble-shRNA as control. Animals with Shp2 downregulation were subjected to either microbead injections or acute ocular hypertension experimental paradigm. Changes in inner retinal function were evaluated by measuring positive scotopic threshold response (pSTR) while structural and biochemical alterations were evaluated through H&E staining, western blotting and immunohistochemical analysis of the retinal tissues. Results: A greater loss of pSTR amplitudes was observed in the WT mice compared to Cav-1-/- retinas in both the models. Silencing of Shp2 phosphatase imparted protection against inner retinal function loss in chronic glaucoma model in WT mice. The functional rescue also translated to structural preservation of ganglion cell layer in the chronic glaucoma condition in WT mice which was not evident in Cav-1-/- mice retinas. Conclusions: This study indicates that protective effects of Shp2 ablation under chronic experimental glaucoma conditions are dependent on Cav-1 in the retina, suggesting in vivo interactions between the two proteins.
Assuntos
Caveolina 1/fisiologia , Terapia Genética , Vetores Genéticos/uso terapêutico , Glaucoma/terapia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Retina/patologia , alfa-Globulinas/genética , Animais , Apoptose , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Caveolina 1/deficiência , Caveolina 1/genética , DNA Complementar/genética , Dependovirus/genética , Quinase 1 de Adesão Focal/fisiologia , Técnicas de Silenciamento de Genes , Genes Reporter , Genes Sintéticos , Glaucoma/metabolismo , Glaucoma/patologia , Integrina beta1/fisiologia , Pressão Intraocular , Injeções Intravítreas , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas , Proteína Tirosina Fosfatase não Receptora Tipo 11/biossíntese , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas Tirosina Quinases/fisiologia , Regulação para CimaRESUMO
Cancer cells function as primary architects of the tumor microenvironment. However, the molecular features of cancer cells that govern stromal cell phenotypes remain unclear. Here, we show that cancer-associated fibroblast (CAF) heterogeneity is driven by lung adenocarcinoma (LUAD) cells at either end of the epithelial-to-mesenchymal transition (EMT) spectrum. LUAD cells that have high expression of the EMT-activating transcription factor ZEB1 reprogram CAFs through a ZEB1-dependent secretory program and direct CAFs to the tips of invasive projections through a ZEB1-driven CAF repulsion process. The EMT, in turn, sensitizes LUAD cells to pro-metastatic signals from CAFs. Thus, CAFs respond to contextual cues from LUAD cells to promote metastasis.
Assuntos
Adenocarcinoma de Pulmão/genética , Fibroblastos Associados a Câncer/metabolismo , Células Epiteliais/metabolismo , Neoplasias Renais/genética , Neoplasias Pulmonares/genética , Células-Tronco Mesenquimais/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/secundário , alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Animais , Fibroblastos Associados a Câncer/patologia , Comunicação Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Receptor com Domínio Discoidina 2/genética , Receptor com Domínio Discoidina 2/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/secundário , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Células-Tronco Mesenquimais/patologia , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Microambiente Tumoral/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismoRESUMO
Although a previous pan-cancer study has reported the expression patterns of ITIHs in various tumors, their analyses have been restricted to limited cancer types. We thus comprehensively analyzed the expression profiles and clinical significances of ITIHs in a broader spectrum of cancers from TCGA. Our results showed that ITIHs were primarily down-regulated in tested cancers. The ITIH members were associated with either survival advantage or disadvantage, depending on the cancer type tested and the genes queried. Importantly, we for the first time demonstrated that ITIH1 had substantially decreased expression in liver hepatocellular carcinoma (LIHC) compared with corresponding normal tissue, and its down-regulation adversely impacted patient outcome. Moreover, ITIH1 expression was consistently declining during the progression of LIHC. Further analysis revealed that ITIH1 may be involved in cellular metabolic processes. Our findings established ITIH1 as a potential diagnostic and prognostic biomarker for LIHC, which awaits future experimental validation.
Assuntos
alfa-Globulinas/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Recidiva Local de Neoplasia/epidemiologia , alfa-Globulinas/análise , Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Conjuntos de Dados como Assunto , Progressão da Doença , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Recidiva Local de Neoplasia/genética , Prognóstico , Intervalo Livre de ProgressãoRESUMO
α1-microglobulin (A1M) is a ubiquitous protein with reductase and radical- and heme-binding properties. The protein is mainly expressed in the liver and encoded by the α1-microglobulin-bikunin precursor (AMBP) gene together with the plasma proteinase inhibitor bikunin. The AMBP polypeptide is translated, glycosylated and the C-terminal bikunin part linked via a chondroitin sulfate glycosaminoglycan chain to one or two heavy chains in the endoplasmic reticulum (ER) and Golgi compartments. After proteolytic cleavage, the A1M protein and complexed bikunin parts are secreted separately. The complete physiological role of A1M, and the reason for the co-synthesis with bikunin, are both still unknown. The aim of this work was to develop an A1M knockout (A1M-KO) mouse model lacking expression of A1M, but with a preserved bikunin expression, and to study the phenotypic traits in these mice, with a focus on hepatic endoplasmic reticulum (ER) function. The bikunin expression was increased in the A1M-KO mouse livers, while the bikunin levels in plasma were decreased, indicating a defective biosynthesis of bikunin. The A1M-KO livers also showed an increased expression of transducers of the unfolded protein response (UPR), indicating an increased ER-stress in the livers. At twelve months of age, the A1M-KO mice also displayed an increased body weight, and an increased liver weight and lipid accumulation. Moreover, the KO mice showed an increased expression of endogenous antioxidants in the liver, but not in the kidneys. Together, these results suggest a physiological role of A1M as a regulator of the intracellular redox environment and more specifically the ER folding and posttranslational modification processes, particularly in the liver.
Assuntos
alfa-Globulinas , Estresse do Retículo Endoplasmático , alfa-Globulinas/genética , Animais , Peso Corporal , Estresse do Retículo Endoplasmático/genética , Camundongos , Camundongos KnockoutRESUMO
α1-microglobulin (A1M) is a small protein present in vertebrates including humans. It has several physiologically relevant properties, including binding of heme and radicals as well as enzymatic reduction, that are used in the protection of cells and tissue. Research has revealed that A1M can ameliorate heme and ROS-induced injuries in cell cultures, organs, explants and animal models. Recently, it was shown that A1M could reduce hemolysis in vitro, observed with several different types of insults and sources of RBCs. In addition, in a recently published study, it was observed that mice lacking A1M (A1M-KO) developed a macrocytic anemia phenotype. Altogether, this suggests that A1M may have a role in RBC development, stability and turnover. This opens up the possibility of utilizing A1M for therapeutic purposes in pathological conditions involving erythropoietic and hemolytic abnormalities. Here, we provide an overview of A1M and its potential therapeutic effect in the context of the following erythropoietic and hemolytic conditions: Diamond-Blackfan anemia (DBA), 5q-minus myelodysplastic syndrome (5q-MDS), blood transfusions (including storage), intraventricular hemorrhage (IVH), preeclampsia (PE) and atherosclerosis.
Assuntos
alfa-Globulinas/genética , Eritrócitos/metabolismo , Eritropoese/genética , Síndromes Mielodisplásicas/genética , alfa-Globulinas/metabolismo , Animais , Feminino , Heme/genética , Heme/metabolismo , Hemólise/genética , Homeostase , Humanos , Camundongos , Camundongos Knockout , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/terapiaRESUMO
The Psychiatric Genomics Consortium (PGC) has recently identified 10 potential functional coding variants for schizophrenia. However, how these coding variants confer schizophrenia risk remains largely unknown. Here, we investigate the associations between eight potential functional coding variants identified by PGC and schizophrenia in a large Han Chinese sample (nâ¯=â¯4022 cases and 9270 controls). Among the eight tested single nucelotide polymorphisms (SNPs), rs3617 (a missense variant, p.K315Q in the ITIH3 gene) showed genome-wide significant association with schizophrenia in the Han Chinese population (Pâ¯=â¯8.36â¯×â¯10-16), with the same risk allele as in PGC. Interestingly, rs3617 is located in a genomic region that is highly evolutionarily conserved, and its schizophrenia risk allele (C allele) was associated with lower ITIH3 mRNA and protein expression. Intriguingly, mouse neural stem cells stably overexpressing ITIH3 with different alleles of rs3617 exhibited significant differences in proliferation, migration, and differentiation, suggesting the impact of rs3617 on neurodevelopment. Subsequent transcriptome analysis found that the differentially expressed genes in neural stem cells stably overexpressing different alleles of rs3617 were significantly enriched in schizophrenia-related pathways, including cell adhesion, synapse assembly, MAPK and PI3K-AKT pathways. Our study provides convergent lines of evidence suggesting that rs3617 in ITIH3 likely affects protein function and neurodevelopment and thereby confers risk of schizophrenia.
Assuntos
alfa-Globulinas/genética , Predisposição Genética para Doença , Transtornos do Neurodesenvolvimento/genética , Esquizofrenia/genética , Adolescente , Adulto , Povo Asiático , Proliferação de Células , China/epidemiologia , Feminino , Humanos , Masculino , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação de Sentido Incorreto/genética , Transtornos do Neurodesenvolvimento/patologia , Fosfatidilinositol 3-Quinases/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fatores de Risco , Esquizofrenia/patologia , Adulto JovemRESUMO
OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is difficult to diagnose at resectable stage. Recent studies have suggested that extracellular vesicles (EVs) contain long RNAs. The aim of this study was to develop a diagnostic (d-)signature for the detection of PDAC based on EV long RNA (exLR) profiling. DESIGN: We conducted a case-control study with 501 participants, including 284 patients with PDAC, 100 patients with chronic pancreatitis (CP) and 117 healthy subjects. The exLR profile of plasma samples was analysed by exLR sequencing. The d-signature was identified using a support vector machine algorithm and a training cohort (n=188) and was validated using an internal validation cohort (n=135) and an external validation cohort (n=178). RESULTS: We developed a d-signature that comprised eight exLRs, including FGA, KRT19, HIST1H2BK, ITIH2, MARCH2, CLDN1, MAL2 and TIMP1, for PDAC detection. The d-signature showed high accuracy, with an area under the receiver operating characteristic curve (AUC) of 0.960, 0.950 and 0.936 in the training, internal validation and external validation cohort, respectively. The d-signature was able to identify resectable stage I/II cancer with an AUC of 0.949 in the combined three cohorts. In addition, the d-signature showed superior performance to carbohydrate antigen 19-9 in distinguishing PDAC from CP (AUC 0.931 vs 0.873, p=0.028). CONCLUSION: This study is the first to characterise the plasma exLR profile in PDAC and to report an exLR signature for the detection of pancreatic cancer. This signature may improve the prognosis of patients who would have otherwise missed the curative treatment window.
Assuntos
Carcinoma Ductal Pancreático/sangue , Carcinoma Ductal Pancreático/diagnóstico , Vesículas Extracelulares/metabolismo , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , RNA/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , alfa-Globulinas/genética , Área Sob a Curva , Antígeno CA-19-9/sangue , Carcinoma Ductal Pancreático/genética , Estudos de Casos e Controles , Criança , Claudina-1/genética , Feminino , Fibrinogênio/genética , Humanos , Queratina-19/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/genética , Neoplasias Pancreáticas/genética , Pancreatite Crônica/sangue , RNA Circular/sangue , RNA Longo não Codificante/sangue , RNA Mensageiro/sangue , Curva ROC , Análise de Sequência de RNA , Máquina de Vetores de Suporte , Inibidor Tecidual de Metaloproteinase-1/genética , Ubiquitina-Proteína Ligases/genética , Adulto JovemRESUMO
Destruction of the cartilage matrix in joints is an important feature of arthritis. Proteolytic degradation of cartilage glycoproteins can contribute to the loss of matrix integrity. Human inter-α-inhibitor (IαI), which stabilizes the extracellular matrix, is composed of the light-chain serine proteinase inhibitor bikunin and two homologous heavy chains (HC1 and HC2) covalently linked through chondroitin 4-sulfate. Inflammation promotes the transfer of HCs from chondroitin 4-sulfate to hyaluronan by tumor necrosis factor-stimulated gene-6 protein (TSG-6). This reaction generates a covalent complex between the heavy chains and hyaluronan that can promote leukocyte invasion. This study demonstrates that both IαI and the HC-hyaluronan complex are substrates for the extracellular matrix proteases ADAMTS-5 and matrix metalloprotease (MMP) -3, -7, and -13. The major cleavage sites for all four proteases are found in the C terminus of HC2. ADAMTS-5 and MMP-7 displayed the highest activity toward HC2. ADAMTS-5 degradation products were identified in mass spectrometric analysis of 29 of 33 arthropathic patients, indicating that ADAMTS-5 cleavage occurs in synovial fluid in arthritis. After cleavage, free HC2, together with TSG-6, is able to catalyze the transfer of heavy chains to hyaluronan. The release of extracellular matrix bound HC2 is likely to increase the mobility of the HC2/TSG-6 catalytic unit and consequently increase the rate of the HC transfer reaction. Ultimately, ADAMTS-5 cleavage of HC2 could alter the physiological and mechanical properties of the extracellular matrix and contribute to the progression of arthritis.
Assuntos
Proteína ADAMTS5/metabolismo , alfa-Globulinas/metabolismo , Artrite/enzimologia , Líquido Sinovial/enzimologia , Proteína ADAMTS5/genética , alfa-Globulinas/química , alfa-Globulinas/genética , Motivos de Aminoácidos , Artrite/genética , Artrite/metabolismo , Matriz Extracelular/enzimologia , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Humanos , Ácido Hialurônico/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Líquido Sinovial/metabolismoRESUMO
In the present study, in order to identify novel diagnostic biomarkers for the malignant behavior of oral squamous cell carcinoma (OSCC), we determined the proteomic profiles of several OSCC cell lines and keratinocytes by two-dimensional fluorescence difference gel electrophoresis and liquid chromatography tandem mass spectrometry. The protein expression level of α-1-microglobulin/bikunin precursor (AMBP) was found to be significantly lower in the OSCC cell lines than in the keratinocytes, and a significant decrease in AMBP mRNA expression was confirmed in the OSCC cell lines by RT-qPCR. To investigate the biological function of AMBP in OSCC, the cells were transiently transfected with an AMBP overexpression vector; the AMBP-overexpressing cells exhibited a significantly decreased invasion and migration in comparison to the mock-transfected control cells, although no significant changes in cell proliferation were observed. Immunohistochemistry revealed that the underexpression of AMBP was significantly associated with a high metastatic potential to cervical lymph nodes and a poor overall survival. Thus, the expression of AMBP is an independent predictive factor of cervical lymph node metastasis and a prognostic factor of overall survival, and it is involved in both cell invasion and metastasis in cervical lymph nodes in OSCC.
Assuntos
alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Regulação para Baixo , Neoplasias Bucais/metabolismo , Proteômica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Análise de SobrevidaRESUMO
ITIH3 and ITIH4 are involved in the stabilization of the extracellular matrix. Several genome-wide association studies and case-control studies regarding psychiatric disorders have identified ITIH3 and ITIH4 single nucleotide polymorphisms (SNPs). The present case-control study examined the relationship between ITIH3 SNPs rs2535629 and rs736408 and ITIH4 SNPs rs3821831 and rs2239547 and depressive symptoms during pregnancy in Japan. Cases comprised 273 women with depressive symptoms during pregnancy defined as a Center for Epidemiological Studies Depression Scale (CES-D) score ≥ 16. Control subjects comprised 1176 women without depressive symptoms during pregnancy, according to the CES-D criteria, who had not been diagnosed with depression by a doctor. Adjustment was made for age, gestation at baseline, region of residence, the presence of children, family structure, smoking, employment, and education. Compared with the TT genotype of ITIH4 SNP rs2239547, the CC genotype was significantly related to a reduced risk of depressive symptoms during pregnancy: the adjusted odds ratio (95% CI) was 0.84 (0.63-1.11) for the TC genotype and 0.57 (0.36-0.91) for the CC genotype. ITIH3 SNPs rs2535629 and rs736408 and ITIH4 SNP rs3821831 were not related to depressive symptoms during pregnancy. The GCCT haplotype of rs2535629, rs736408, rs3821831, and rs2239547 was significantly positively associated with depressive symptoms during pregnancy. A significant interaction was found between rs2239547 and the presence of children. This is the first study to show significant associations of ITIH4 SNP rs2239547 and the GCCT haplotype with depressive symptoms during pregnancy. The effect of the presence of children might depend on rs2239547.
Assuntos
alfa-Globulinas/genética , Proteínas Sanguíneas/genética , Depressão/genética , Glicoproteínas/genética , Polimorfismo de Nucleotídeo Único , Complicações na Gravidez/genética , Proteínas Secretadas Inibidoras de Proteinases/genética , Adulto , alfa-Globulinas/fisiologia , Povo Asiático/genética , Proteínas Sanguíneas/fisiologia , Estudos de Casos e Controles , Depressão/etnologia , Depressão/psicologia , Família , Feminino , Interação Gene-Ambiente , Genótipo , Glicoproteínas/fisiologia , Haplótipos , Humanos , Relações Mãe-Filho , Gravidez , Complicações na Gravidez/etnologia , Complicações na Gravidez/psicologia , Estudos Prospectivos , Proteínas Secretadas Inibidoras de Proteinases/fisiologia , Fumar/epidemiologia , Fumar/genética , Fatores SocioeconômicosRESUMO
A full-length cDNA clone encoding grass carp (Ctenopharyngodon idellus) α1-microglobulin/bikunin precursor (Ci-AMBP) was isolated by subtracted differential hybridization screening from a liver cDNA library. The deduced amino acid sequence shared approximately 50% sequence identity with its mammalian counterparts, but more than 90% identity with another fish species. AMBPs are the precursors of the plasma glycoproteins α1-microglobulin (α1m) and bikunin. Both peptide structures and their chromosomal organization were well conserved in Ci-AMBP. The α1m and bikunin polypeptides are separated by the typical tetrapeptide R-A-R-R that provides an endoproteolytic cleavage site for maturation. The genetic organization of domains and functional motifs indicated that Ci-AMBP is a typical member of the lipocalin and Kunitz-type protease inhibitor superfamilies. Expression of the Ci-AMBP gene in different tissues/organs was evaluated using semi-quantitative RT-PCR and, in contrast to the restricted expression in other species, transcripts were detected in a wide range of tissues. The most abundant expression occurred in the secretory organs, which supports the roles of α1m and bikunin in the immune response to diseases and in the stress response.
Assuntos
alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Carpas/metabolismo , alfa-Globulinas/química , Sequência de Aminoácidos , Animais , Carpas/genética , Clonagem Molecular , Sequência Conservada , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Fígado/metabolismo , Família Multigênica , Conformação Proteica , Distribuição TecidualRESUMO
BACKGROUND: α1-Microglobulin (A1M) is a reductase and radical scavenger involved in physiological protection against oxidative damage. These functions were previously shown to be dependent upon cysteinyl-, C34, and lysyl side-chains, K(92, 118,130). A1M binds heme and the crystal structure suggests that C34 and H123 participate in a heme binding site. We have investigated the involvement of these five residues in the interactions with heme. METHODS: Four A1M-variants were expressed: with cysteine to serine substitution in position 34, lysine to threonine substitutions in positions (92, 118, 130), histidine to serine substitution in position 123 and a wt without mutations. Heme binding was investigated by tryptophan fluorescence quenching, UV-Vis spectrophotometry, circular dichroism, SPR, electrophoretic migration shift, gel filtration, catalase-like activity and molecular simulation. RESULTS: All A1M-variants bound to heme. Mutations in C34, H123 or K(92, 118, 130) resulted in significant absorbance changes, CD spectral changes, and catalase-like activity, suggesting involvement of these side-groups in coordination of the heme-iron. Molecular simulation support a model with two heme-binding sites in A1M involving the mutated residues. Binding of the first heme induces allosteric stabilization of the structure predisposing for a better fit of the second heme. CONCLUSIONS: The results suggest that one heme-binding site is located in the lipocalin pocket and a second binding site between loops 1 and 4. Reactions with the hemes involve the side-groups of C34, K(92, 118, 130) and H123. GENERAL SIGNIFICANCE: The model provides a structural basis for the functional activities of A1M: heme binding activity of A1M.
Assuntos
alfa-Globulinas/química , Heme/química , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Sítios de Ligação/genética , Western Blotting , Dicroísmo Circular , Heme/metabolismo , Humanos , Mutagênese Sítio-Dirigida/métodos , Mutação , Oxirredução , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrometria de Fluorescência , Ressonância de Plasmônio de SuperfícieRESUMO
We present data that hyaluronan (HA) polysaccharides, about 14-86 monosaccharides in length, are capable of accepting only a single heavy chain (HC) from inter-α-inhibitor via transfer by tumor necrosis factor-stimulated gene 6 (TSG-6) and that this transfer is irreversible. We propose that either the sulfate groups (or the sulfation pattern) at the reducing end of the chondroitin sulfate (CS) chain of bikunin, or the core protein itself, enables the bikunin proteoglycan (PG) to accept more than a single HC and permits TSG-6 to transfer these HCs from its relatively small CS chain to HA. To test these hypotheses, we investigated HC transfer to the intact CS chain of the bikunin PG, and to the free chain of bikunin. We observed that both the free CS chain and the intact bikunin PG were only able to accept a single HC from inter-α-inhibitor via transfer by TSG-6 and that HCs could be swapped from the bikunin PG and its free CS chain to HA. Furthermore, a significant portion of the bikunin PG was unable to accept a single heavy chain. We discuss explanations for these observations, including the intracellular assembly of inter-α-inhibitor. In summary, these data demonstrate that the sulfation of the CS chain of bikunin and/or its core protein promote HC transfer by TSG-6 to its relatively short CS chain, although they are insufficient to enable the CS chain of bikunin to accept more than one HC in the absence of other cofactors.
Assuntos
alfa-Globulinas/metabolismo , Moléculas de Adesão Celular/metabolismo , Sulfatos de Condroitina/metabolismo , Ácido Hialurônico/metabolismo , alfa-Globulinas/genética , Animais , Moléculas de Adesão Celular/genética , Sulfatos de Condroitina/genética , Ácido Hialurônico/genética , CamundongosRESUMO
Cereal prolamins, which are alcohol-soluble seed storage proteins, can induce ER-derived protein bodies (PBs) in heterologous tissue. Like maize and wheat prolamins, rice prolamins can form ER-derived PBs, but the region of mature polypeptides that is essential for PB formation has not been identified. In this study, we examined the formation mechanisms of ER-derived PB-like structures by expressing rice 13 kDa prolamin-deletion mutants fused to green fluorescent protein (GFP) in heterologous tissues such as yeast. The 13 kDa prolamin-GFP fusion protein was stably accumulated in transgenic yeast and formed an ER-derived PB-like structure. In contrast, rice α-globulin-GFP fusion protein was transported to vacuoles. In addition, the middle and COOH-terminal regions of 13 kDa prolamin formed ER-derived PB-like structures, whereas the NH2-terminal region of 13 kDa prolamin did not form such structures. These results suggest that the middle and COOH-terminal regions of 13 kDa prolamin can be retained and thus can induce ER-derived PB in yeast.
Assuntos
Oryza/genética , Prolaminas/química , Proteínas Recombinantes de Fusão/química , Sementes/genética , alfa-Globulinas/química , alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Retículo Endoplasmático/metabolismo , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Oryza/metabolismo , Plasmídeos/química , Plasmídeos/metabolismo , Prolaminas/genética , Prolaminas/metabolismo , Transporte Proteico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Sementes/metabolismo , Vacúolos/metabolismoRESUMO
We have previously demonstrated that the Src family kinase Yes, the Yes-associated protein (YAP) and TEA domain TEAD2 transcription factor pathway are activated by leukemia inhibitory factor (LIF) and contribute to mouse embryonic stem (mES) cell maintenance of pluripotency and self-renewal. In addition, we have shown that fetal bovine serum (FBS) induces Yes auto-phosphorylation and activation. In the present study we confirm that serum also activates TEAD-dependent transcription in a time- and dose-dependent manner and we identify Inter-α-inhibitor (IαI) as a component in serum capable of activating the Yes/YAP/TEAD pathway by inducing Yes auto-phosphorylation, YAP nuclear localization and TEAD-dependent transcription. The cleaved heavy chain 2 (HC2) sub-component of IαI, is demonstrated to be responsible for this effect. Moreover, IαI is also shown to efficiently increase expression of TEAD-downstream target genes including well-known stem cell factors Nanog and Oct 3/4. IαI is not produced by the ES cells per se but is added to the cells via the cell culture medium containing serum or serum-derived components such as bovine serum albumin (BSA). In conclusion, we describe a novel function of IαI in activating key pluripotency pathways associated with ES cell maintenance and self-renewal.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , alfa-Globulinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Embrionárias/metabolismo , Fosfoproteínas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-yes/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , alfa-Globulinas/genética , Animais , Bovinos , Proteínas de Ciclo Celular , Núcleo Celular/genética , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Células-Tronco Embrionárias/citologia , Ativação Enzimática/fisiologia , Humanos , Camundongos , Fosfoproteínas/genética , Células-Tronco Pluripotentes/citologia , Proteínas Proto-Oncogênicas c-yes/genética , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Proteínas de Sinalização YAPRESUMO
Mesotrypsin is an isoform of trypsin that is uniquely resistant to polypeptide trypsin inhibitors and can cleave some inhibitors rapidly. Previous studies have shown that the amyloid precursor protein Kunitz protease inhibitor domain (APPI) is a specific substrate of mesotrypsin and that stabilization of the APPI cleavage site in a canonical conformation contributes to recognition by mesotrypsin. We hypothesized that other proteins possessing potential cleavage sites stabilized in a similar conformation might also be mesotrypsin substrates. Here we evaluated a series of candidate substrates, including human Kunitz protease inhibitor domains from amyloid precursor-like protein 2 (APLP2), bikunin, hepatocyte growth factor activator inhibitor type 2 (HAI2), tissue factor pathway inhibitor-1 (TFPI1), and tissue factor pathway inhibitor-2 (TFPI2), as well as E-selectin, an unrelated protein possessing a potential cleavage site displaying canonical conformation. We find that Kunitz domains within APLP2, bikunin, and HAI2 are cleaved by mesotrypsin with kinetic profiles of specific substrates. TFPI1 and TFPI2 Kunitz domains are cleaved less efficiently by mesotrypsin, and E-selectin is not cleaved at the anticipated site. Cocrystal structures of mesotrypsin with HAI2 and bikunin Kunitz domains reveal the mode of mesotrypsin interaction with its canonical substrates. Our data suggest that major determinants of mesotrypsin substrate specificity include sequence preferences at the P1 and P'2 positions along with conformational stabilization of the cleavage site in the canonical conformation. Mesotrypsin up-regulation has been implicated previously in cancer progression, and proteolytic clearance of Kunitz protease inhibitors offers potential mechanisms by which mesotrypsin may mediate pathological effects in cancer.
Assuntos
Inibidores de Proteases/química , Conformação Proteica , Estrutura Terciária de Proteína , Tripsina/química , alfa-Globulinas/química , alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Sequência de Aminoácidos , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Aprotinina/química , Aprotinina/genética , Aprotinina/metabolismo , Sítios de Ligação/genética , Cristalografia por Raios X , Selectina E/química , Selectina E/genética , Selectina E/metabolismo , Glicoproteínas/química , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Cinética , Lipoproteínas/química , Lipoproteínas/genética , Lipoproteínas/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Inibidores de Proteases/metabolismo , Ligação Proteica , Especificidade por Substrato , Tripsina/genética , Tripsina/metabolismoRESUMO
AIM: Experimental and clinical studies showed that bikunin, a Kunitz-type protease inhibitor, found in urine and amniotic fluid has a role in spread of tumor cells by providing a significant reduction in the levels of urokinase-type plasminogen activator (uPA) and its specific receptor urokinase-type plasminogen activator receptor (uPAR). The aim of this study was to investigate expression of bikunin at the mRNA level and screen for mutations in exon sequence in renal cell carcinoma (RCC) tissues. MATERIALS AND METHODS: Total RNA and DNA were extracted from paired normal and tumor tissues of total 50 RCC (11 papillary, 8 chromophobe, 26 clear cell, and 5 other types) patients (23 females, mean age: 53.55 ± 14.17; 27 males mean age: 62.1 ± 7.92). Bikunin mRNA levels were detected using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Mutational screening was performed by using single strand conformation polymorphism (SSCP) method and nucleotide sequence analysis. RESULTS: There was a statistically significant decrease in the 25 (50%) of tumor tissues comparing to normal tissues in terms of mRNA levels of bikunin (Wilcoxon signed rank test, p = 0.0337). According to the classification based on subtypes of RCC; clear cell RCC samples displayed a reduced gene expression (p = 0.0148). Additionally, the patients with the age above 50 had low bikunin expression. The SNP rs80057939 spanning 4(th) exon of bikunin was detected in 13 tumor tissues. However, it was not statistically significant (p > 0.05). CONCLUSION: Decreased bikunin mRNA level in renal cells might be associated with poor prognosis of renal carcinoma. Therefore, gene constructs or exogenous administration of bikunin might be a potential adjuvant therapy for RCC treatment.
Assuntos
alfa-Globulinas/genética , Carcinoma de Células Renais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/mortalidade , Análise Mutacional de DNA , Éxons , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Carga TumoralRESUMO
Hyaluronan (HA) is an extracellular matrix glycosaminoglycan that is present in pancreatic islets, but little is known about its involvement in the development of human type 1 diabetes (T1D). We have evaluated whether pancreatic islets and lymphoid tissues of T1D and nondiabetic organ donors differ in the amount and distribution of HA and HA-binding proteins (hyaladherins), such as inter-α-inhibitor (IαI), versican, and tumor necrosis factor-stimulated gene-6 (TSG-6). HA was dramatically increased both within the islet and outside the islet endocrine cells, juxtaposed to islet microvessels in T1D. In addition, HA was prominent surrounding immune cells in areas of insulitis. IαI and versican were present in HA-rich areas of islets, and both molecules accumulated in diabetic islets and regions exhibiting insulitis. TSG-6 was observed within the islet endocrine cells and in inflammatory infiltrates. These patterns were only observed in tissues from younger donors with disease duration of <10 years. Furthermore, HA and IαI amassed in follicular germinal centers and in T-cell areas in lymph nodes and spleens in T1D patients compared with control subjects. Our observations highlight potential roles for HA and hyaladherins in the pathogenesis of diabetes.
Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Inflamação/metabolismo , Ilhotas Pancreáticas/metabolismo , Tecido Linfoide/metabolismo , Adulto , Idoso , Envelhecimento , alfa-Globulinas/genética , alfa-Globulinas/metabolismo , Estudos de Casos e Controles , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Criança , Pré-Escolar , Regulação da Expressão Gênica , Humanos , Receptores de Hialuronatos/genética , Lactente , Insulina/metabolismo , Pessoa de Meia-Idade , Versicanas/genética , Versicanas/metabolismoRESUMO
As a major extracellular matrix component, ITIHs played an important role in inflammation and carcinogenesis. Several genome-wide association studies have reported that some positive signals which were derived from the tight linkage disequilibrium region on chromosome 3p21 were associated with both schizophrenia and bipolar disorders in the Caucasian population. To further investigate whether this genomic region is also a susceptibility locus of schizophrenia and major depressive disorder in the Han Chinese population, we conducted this study by recruiting 1235 schizophrenia patients, 1045 major depressive disorder patients and 1235 healthy control subjects in the Han Chinese samples for a case-control study. We genotyped seven SNPs within this region using TaqMan® technology. We found that rs2710322 was significantly associated with schizophrenia (adjusted P(allele) = 0.0018, adjusted P(genotype) = 0.006, OR [95% CI] = 1.278 [1.117-1.462]) while rs1042779 was weakly associated with schizophrenia (adjusted P(allele) = 0.048, OR [95% CI] = 1.164 [1.040-1.303]) and major depressive disorder (adjusted P(allele) = 0.042, OR [95% CI] = 1.178 [1.047-1.326]); it was also our finding that rs3821831 was positively associated with major depressive disorder (adjusted P(allele) = 0.003, adjusted P(genotype) = 0.006, OR [95% CI] = 1.426 [1.156-1.760]). Furthermore, no haplotype was found to be associated with schizophrenia and major depressive disorder. Via the association analysis which combines the schizophrenia and major depressive disorder cases, we also notice that rs1042779 and rs3821831 were significantly associated with combined cases (rs1042779: adjusted P(allele) = 0.012, adjusted P(genotype) = 0.018, OR [95% CI] = 1.171 [1.060-1.292]; rs3821831:adjusted P(genotype) = 0.012, OR [95% CI] = 1.193 [1.010-1.410]). Our results revealed that the shared genetic risk factors of both schizophrenia and major depressive disorder exist in ITIH family genes in the Han Chinese population.