Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Reprod Med Biol ; 20(3): 352-360, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34262404

RESUMO

PURPOSE: Although non-invasive prenatal testing (NIPT) based on cell-free DNA (cfDNA) in maternal plasma has been prevailing worldwide, low levels of fetal DNA fraction may lead to false-negative results. Since fetal cells in maternal blood provide a pure source of fetal genomic DNA, we aimed to establish a workflow to isolate and sequence fetal nucleated red blood cells (fNRBCs) individually as a target for NIPT. METHODS: Using male-bearing pregnancy cases, we isolated fNRBCs individually from maternal blood by FACS, and obtained their genomic sequence data through PCR screening with a Y-chromosome marker and whole-genome amplification (WGA)-based whole-genome sequencing. RESULTS: The PCR and WGA efficiencies of fNRBC candidates were consistently lower than those of control cells. Sequencing data analyses revealed that although the majority of the fNRBC candidates were confirmed to be of fetal origin, many of the WGA-based genomic libraries from fNRBCs were considered to have been amplified from a portion of genomic DNA. CONCLUSIONS: We established a workflow to isolate and sequence fNRBCs individually. However, our results demonstrated that, to make cell-based NIPT targeting fNRBCs feasible, cell isolation procedures need to be further refined such that the nuclei of fNRBCs are kept intact.

2.
Bioorg Med Chem ; 27(1): 196-207, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30522899

RESUMO

Collagen degradation and proMMP-2 activation are major functions of MT1-MMP to promote cancer cell invasion. Since both processes require MT1-MMP homodimerization on the cell surface, herein we propose that the use of bifunctional inhibitors of this enzyme could represent an innovative approach to efficiently reduce tumor growth. A small series of symmetrical dimers derived from previously described monomeric arylsulfonamide hydroxamates was synthesized and tested in vitro on isolated MMPs. A nanomolar MT1-MMP inhibitor, compound 6, was identified and then submitted to cell-based assays on HT1080 fibrosarcoma cells. Dimer 6 reduced MT1-MMP-dependent proMMP-2 activation, collagen degradation and collagen invasion in a dose-dependent manner with better results even compared to its monomeric analogue 4. This preliminary study suggests that dimeric MT1-MMP inhibitors might be further developed and exploited as an alternative tool to reduce cancer cell invasion.


Assuntos
Ácidos Hidroxâmicos/farmacologia , Metaloproteinase 14 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Sulfonamidas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Colágeno/metabolismo , Desenho de Fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Inibidores de Metaloproteinases de Matriz/síntese química , Inibidores de Metaloproteinases de Matriz/química , Simulação de Dinâmica Molecular , Estrutura Molecular , Multimerização Proteica/efeitos dos fármacos , Sulfonamidas/síntese química , Sulfonamidas/química
3.
J Biol Chem ; 292(16): 6633-6643, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28270508

RESUMO

Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane-bound MMP that is highly expressed in cells with invading capacity, including fibroblasts and invasive cancer cells. However, pathways of MT1-MMP up-regulation are not clearly understood. A potential physiological stimulus for MT1-MMP expression is fibrillar collagen, and it has been shown that it up-regulates both MT1-MMP gene and functions in various cell types. However, the mechanisms of collagen-mediated MT1-MMP activation and its physiological relevance are not known. In this study, we identified discoidin domain receptor 2 (DDR2) as a crucial receptor that mediates this process in human fibroblasts. Knocking down DDR2, but not the ß1 integrin subunit, a common subunit for all collagen-binding integrins, inhibited the collagen-induced MT1-MMP-dependent activation of pro-MMP-2 and up-regulation of MT1-MMP at the gene and protein levels. Interestingly, DDR2 knockdown or pharmacological inhibition of DDR2 also inhibited the MT1-MMP-dependent cellular degradation of collagen film, suggesting that cell-surface collagen degradation by MT1-MMP involves DDR2-mediated collagen signaling. This DDR2-mediated mechanism is only present in non-transformed mesenchymal cells as collagen-induced MT1-MMP activation in HT1080 fibrosarcoma cells and MT1-MMP function in MDA-MB231 breast cancer cells were not affected by DDR kinase inhibition. DDR2 activation was found to be noticeably more effective when cells were stimulated by collagen without the non-helical telopeptide region compared with intact collagen fibrils. Furthermore, DDR2-dependent MT1-MMP activation by cartilage was found to be more efficient when the tissue was partially damaged. These data suggest that DDR2 is a microenvironment sensor that regulates fibroblast migration in a collagen-rich environment.


Assuntos
Colágeno Tipo II/metabolismo , Receptor com Domínio Discoidina 2/metabolismo , Fibroblastos/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Animais , Neoplasias da Mama/metabolismo , Cartilagem/metabolismo , Bovinos , Linhagem Celular Tumoral , Feminino , Gelatina/química , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Integrina beta1/metabolismo , Integrinas/metabolismo , Microscopia Confocal , Reação em Cadeia da Polimerase , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Transdução de Sinais
4.
J Cell Sci ; 127(Pt 6): 1203-13, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24463815

RESUMO

The membrane-anchored collagenase membrane type 1 matrix metalloprotease (MT1-MMP) has been shown to play an essential role during epithelial tubulogenesis in 3D collagen matrices; however, its regulation during tubulogenesis is not understood. Here, we report that degradation of collagen in polarized epithelial cells is post-translationally regulated by changing the localization of MT1-MMP from the apical to the basal surface. MT1-MMP predominantly localizes at the apical surface in inert polarized epithelial cells, whereas treatment with HGF induced basal localization of MT1-MMP followed by collagen degradation. The basal localization of MT1-MMP requires the ectodomains of the enzyme because deletion of the MT-loop region or the hemopexin domain inhibited basal localization of the enzyme. TGFß is a well-known inhibitor of tubulogenesis and our data indicate that its mechanism of inhibition is, at least in part, due to inhibition of MT1-MMP localization to the basal surface. Interestingly, however, the effect of TGFß was found to be bi-phasic: at high doses it effectively inhibited basal localization of MT1-MMP, whereas at lower doses tubulogenesis and basal localization of MT1-MMP was promoted. Taken together, these data indicate that basal localization of MT1-MMP is a key factor promoting the degradation of extracellular matrix by polarized epithelial cells, and that this is an essential part of epithelial morphogenesis in 3D collagen.


Assuntos
Membrana Celular/enzimologia , Colágeno/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Animais , Movimento Celular , Polaridade Celular , Meios de Cultura , Cães , Fator de Crescimento de Hepatócito/fisiologia , Humanos , Células Madin Darby de Rim Canino , Camundongos , Organogênese , Transporte Proteico , Proteólise
5.
J Biol Chem ; 288(49): 35126-37, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24165131

RESUMO

Localization of membrane type I matrix metalloproteinase (MT1-MMP) to the leading edge is thought to be a crucial step during cancer cell invasion. However, its mechanisms and functional impact on cellular invasion have not been clearly defined. In this report, we have identified the MT-LOOP, a loop region in the catalytic domain of MT1-MMP ((163)PYAYIREG(170)), as an essential region for MT1-MMP to promote cellular invasion. Deletion of the MT-LOOP effectively inhibited functions of MT1-MMP on the cell surface, including proMMP-2 activation, degradation of gelatin and collagen films, and cellular invasion into a collagen matrix. This is not due to loss of the catalytic function of MT1-MMP but due to inefficient localization of the enzyme to ß1-integrin-rich cell adhesion complexes at the plasma membrane. We also found that an antibody that specifically recognizes the MT-LOOP region of MT1-MMP (LOOPAb) inhibited MT1-MMP functions, fully mimicking the phenotype of the MT-LOOP deletion mutant. We therefore propose that the MT-LOOP region is an interface for molecular interactions that mediate enzyme localization to cell adhesion complexes and regulate MT1-MMP functions. Our findings have revealed a novel mechanism regulating MT1-MMP during cellular invasion and have identified the MT-LOOP as a potential exosite target region to develop selective MT1-MMP inhibitors.


Assuntos
Adesão Celular/fisiologia , Metaloproteinase 14 da Matriz/química , Metaloproteinase 14 da Matriz/fisiologia , Invasividade Neoplásica/fisiopatologia , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Precursores Enzimáticos/metabolismo , Matriz Extracelular/fisiologia , Gelatinases/metabolismo , Células HeLa , Humanos , Metaloproteinase 14 da Matriz/genética , Modelos Biológicos , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência
6.
Antioxidants (Basel) ; 13(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38929143

RESUMO

Many countries, including Japan, are experiencing declining birth rates. Assisted reproductive technologies have consistently demonstrated good results in resolving infertility. Although the development of fertilized eggs into blastocysts has been recognized as a crucial step in assisted reproductive technologies, the involved mechanisms are currently unclear. Here, we established a new culture system for the in vitro development of fertilized eggs into blastocysts. In the Transwell culture system, the rate of blastocysts hatching from fertilized eggs cultured with adipose-derived stem cells (ASCs) was significantly higher than that of blastocysts cultured only with fertilized eggs. Gene ontology analysis revealed that the developed blastocysts displayed essential gene expression patterns in mature blastocysts. Additionally, when cultured with 3rd-passage ASCs, the developed blastocysts expressed the core genes for blastocyst maturation and antioxidant properties compared to those cultured only with fertilized eggs or cultured with 20th-passage ASCs. These results suggest that the Transwell culture system may imitate the in vivo tubal culture state for fertilized eggs. Exosomes derived from stem cells with stemness potential play a powerful role in the development of blastocysts from fertilized eggs. Additionally, the exosomes expressed specific microRNAs; therefore, the Transwell culture system resulted in a higher rate of pregnancy. In future, the extraction of their own extracellular vesicles from the culture medium might contribute to the development of novel assisted reproductive technologies.

7.
PLoS Biol ; 8(8)2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20808951

RESUMO

Cis-regulatory modules that drive precise spatial-temporal patterns of gene expression are central to the process of metazoan development. We describe a new computational strategy to annotate genomic sequences based on their "pattern generating potential" and to produce quantitative descriptions of transcriptional regulatory networks at the level of individual protein-module interactions. We use this approach to convert the qualitative understanding of interactions that regulate Drosophila segmentation into a network model in which a confidence value is associated with each transcription factor-module interaction. Sequence information from multiple Drosophila species is integrated with transcription factor binding specificities to determine conserved binding site frequencies across the genome. These binding site profiles are combined with transcription factor expression information to create a model to predict module activity patterns. This model is used to scan genomic sequences for the potential to generate all or part of the expression pattern of a nearby gene, obtained from available gene expression databases. Interactions between individual transcription factors and modules are inferred by a statistical method to quantify a factor's contribution to the module's pattern generating potential. We use these pattern generating potentials to systematically describe the location and function of known and novel cis-regulatory modules in the segmentation network, identifying many examples of modules predicted to have overlapping expression activities. Surprisingly, conserved transcription factor binding site frequencies were as effective as experimental measurements of occupancy in predicting module expression patterns or factor-module interactions. Thus, unlike previous module prediction methods, this method predicts not only the location of modules but also their spatial activity pattern and the factors that directly determine this pattern. As databases of transcription factor specificities and in vivo gene expression patterns grow, analysis of pattern generating potentials provides a general method to decode transcriptional regulatory sequences and networks.


Assuntos
Padronização Corporal , Biologia Computacional/métodos , Drosophila/embriologia , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Padronização Corporal/genética , Drosophila/genética , Drosophila/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Modelos Genéticos , Ligação Proteica , Software , Fatores de Transcrição/genética
8.
Cureus ; 15(6): e40610, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37476114

RESUMO

Chordomas are rare, locally aggressive, primary bone tumors derived from primitive notochord remnants. They almost always arise within the axial skeleton, particularly in the skull base and the sacrococcygeal region. They usually present as extradural tumors, but rarely, they present as entirely intradural tumors. This report describes a case of intradural chordoma that mimicked an epidermoid cyst. A 72-year-old woman was incidentally found to have a prepontine extra-axial mass on magnetic resonance imaging. The mass gradually increased in size, and she felt discomfort in the right cheek area. The mass showed similar signal intensity to cerebrospinal fluid on T1-weighted images and T2-weighted images, but high signal intensity on fluid-attenuated inversion recovery images and diffusion-weighted images. Because the presence of very faint contrast enhancement was not noticed, the mass was preoperatively diagnosed as an epidermoid cyst. Tumor resection was performed, and the histopathological diagnosis was chondroid chordoma. Since intradural chordoma may resemble an epidermoid cyst on imaging, radiologists should check carefully for the presence of contrast enhancement and suggest the possibility of intradural chordoma.

9.
Kurume Med J ; 68(1): 1-8, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36754380

RESUMO

Currently, there is no surgical assistance system that can perform a three-dimensional (3D) planned total hip arthroplasty (THA) by methods other than surgical assistance navigation or robots. However, they are expensive, cumbersome, and subject to additional invasiveness, so there is a need for a simpler and less expensive 3D surgical support system. In this study, THA was performed using the anterolateral approach (Watson-Jones) in the supine position in 23 subjects to examine the efficacy and safety of a patient-specific femoral guide linked to 3D surgery support software. In 48% of the subjects, the difference in anterior torsion angle from the preoperative plan was within ±5 degrees, while in 83% of the subjects, the difference was within ±10 degrees. The 95% confidence interval (4.61-8.70) of the absolute difference did not fall below the pre-defined threshold of 7.2 degrees (p = 0.293). No adverse events were observed other than 2 cases (8.7%) of hemorrhage that required a blood transfusion. We confirmed the efficacy and safety of the patient-specific femoral guide in anterolateral supine approach THA.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Cirurgia Assistida por Computador , Humanos , Artroplastia de Quadril/métodos , Fêmur/cirurgia , Software , Cirurgia Assistida por Computador/métodos
10.
Life Sci Alliance ; 6(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37369603

RESUMO

Niemann-Pick disease type C1 (NPC1) is a fatal lysosomal storage disorder characterized by progressive neuronal degeneration. Its key pathogenic events remain largely unknown. We have, herein, found that neonatal BM-derived cell transplantation can ameliorate Purkinje cell degeneration in NPC1 mice. We subsequently addressed the impact of the peripheral immune system on the neuropathogenesis observed in NPC1 mice. The depletion of mature lymphocytes promoted NPC1 phenotypes, thereby suggesting a neuroprotective effect of lymphocytes. Moreover, the peripheral infusion of CD4-positive cells (specifically, of regulatory T cells) from normal healthy donor ameliorated the cerebellar ataxic phenotype and enhanced the survival of Purkinje cells. Conversely, the depletion of regulatory T cells enhanced the onset of the neurological phenotype. On the other hand, circulating inflammatory monocytes were found to be involved in the progression of Purkinje cell degeneration, whereas the depletion of resident microglia had little effect. Our findings reveal a novel role of the adaptive and the innate immune systems in NPC1 neuropathology.


Assuntos
Doença de Niemann-Pick Tipo C , Células de Purkinje , Camundongos , Animais , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Doença de Niemann-Pick Tipo C/genética , Cerebelo/metabolismo , Sistema Imunitário/metabolismo , Microglia/metabolismo
11.
J Biol Chem ; 286(9): 7587-600, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21193411

RESUMO

Homodimerization is an essential step for membrane type 1 matrix metalloproteinase (MT1-MMP) to activate proMMP-2 and to degrade collagen on the cell surface. To uncover the molecular basis of the hemopexin (Hpx) domain-driven dimerization of MT1-MMP, a crystal structure of the Hpx domain was solved at 1.7 Å resolution. Two interactions were identified as potential biological dimer interfaces in the crystal structure, and mutagenesis studies revealed that the biological dimer possesses a symmetrical interaction where blades II and III of molecule A interact with blades III and II of molecule B. The mutations of amino acids involved in the interaction weakened the dimer interaction of Hpx domains in solution, and incorporation of these mutations into the full-length enzyme significantly inhibited dimer-dependent functions on the cell surface, including proMMP-2 activation, collagen degradation, and invasion into the three-dimensional collagen matrix, whereas dimer-independent functions, including gelatin film degradation and two-dimensional cell migration, were not affected. These results shed light on the structural basis of MT1-MMP dimerization that is crucial to promote cellular invasion.


Assuntos
Matriz Extracelular/enzimologia , Hemopexina/química , Hemopexina/metabolismo , Metaloproteinase 14 da Matriz/química , Metaloproteinase 14 da Matriz/metabolismo , Animais , Células COS , Chlorocebus aethiops , Cristalografia , Dimerização , Ativação Enzimática/fisiologia , Células HeLa , Hemopexina/genética , Humanos , Metaloproteinase 14 da Matriz/genética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutagênese , Estrutura Terciária de Proteína , Solubilidade , Relação Estrutura-Atividade
12.
Matrix Biol ; 107: 1-23, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35122963

RESUMO

MT1-MMP plays a crucial role in promoting the cellular invasion of cancer cells by degrading the extracellular matrix to create a path for migration. During this process, its localization at the leading edge of migrating cells is critical, and it is achieved by targeted transport of MT1-MMP-containing vesicles along microtubules by kinesin superfamily motor proteins (KIFs). Here we identified three KIFs involved in MT1-MMP vesicle transport: KIF3A, KIF13A, and KIF9. Knockdown of KIF3A and KIF13A effectively inhibited MT1-MMP-dependent collagen degradation and invasion, while knockdown of KIF9 increased collagen degradation and invasion. Our data suggest that KIF3A/KIF13A dependent MT1-MMP vesicles transport takes over upon KIF9 knockdown. Live-cell imaging analyses have indicated that KIF3A and KIF13A coordinate to transport the same MT1-MMP-containing vesicles from the trans-Golgi to the endosomes, and KIF13A alone transports the vesicle from the endosome to the plasma membrane. Taken together, we have identified a unique interplay between three KIFs to regulate leading edge localization of MT1-MMP and MT1-MMP-dependent cancer cell invasion.


Assuntos
Cinesinas , Metaloproteinase 14 da Matriz , Linhagem Celular Tumoral , Movimento Celular , Endossomos/metabolismo , Matriz Extracelular/metabolismo , Humanos , Cinesinas/genética , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Invasividade Neoplásica
13.
Lab Invest ; 91(7): 992-1006, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21403644

RESUMO

Molecular mechanisms and signaling pathways leading to cellular proliferation and lesion formation in the crescentic glomerulonephritis (CGN) remain elusive. In the present study we have explored a potential role of the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway and amino acid transporter (LAT) in the pathogenesis of CGN. Immunohistochemistry and western blot analysis of glomeruli isolated from a rat model of CGN revealed that activation of mTORC1 preceded crescent formation in glomerular parietal epithelial cells (PECs) and podocytes. Daily treatment of rats with the mTOR inhibitor everolimus just after induction of CGN was not beneficial and instead led to increased cellular necrosis of PECs. However, daily treatment starting 7 days after the onset of CGN was beneficial and maintained intact glomeruli. Out of three forms of L-type neutral amino acid transporters (LAT1-LAT3) studied here, only LAT2 was found to be upregulated in the PECs and podocytes in advance of the crescent formation as well as in the crescent lesion itself. Cell culture study revealed that plasma membrane expression of LAT2 markedly stimulated mTORC1 signaling pathway, which was significantly abrogated by coexistence of LAT inhibitor. Finally, LAT inhibitor significantly abrogated development of crescent formation of CGN on day 7. Our data suggest that LAT2 may have a pivotal role in the pathogenesis of CGN by activating the mTORC1 pathway in the glomerular epithelial cells.


Assuntos
Sistema y+ de Transporte de Aminoácidos/fisiologia , Cadeias Leves da Proteína-1 Reguladora de Fusão/fisiologia , Glomerulonefrite/fisiopatologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Sequência de Bases , Western Blotting , Primers do DNA , Feminino , Glomerulonefrite/etiologia , Imuno-Histoquímica , Ratos , Ratos Endogâmicos WKY , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
14.
Lab Invest ; 91(11): 1584-95, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21876538

RESUMO

Although podocyte damage is known to be responsible for the development of minimal-change disease (MCD), the underlying mechanism remains to be elucidated. Previously, using a rat MCD model, we showed that endoplasmic reticulum (ER) stress in the podocytes was associated with the heavy proteinuric state and another group reported that a mammalian target of rapamycin complex 1 (mTORC1) inhibitor protected against proteinuria. In this study, which utilized a rat MCD model, a combination of immunohistochemistry, dual immunofluorescence and confocal microscopy, western blot analysis, and quantitative real-time RT-PCR revealed co-activation of the unfolded protein response (UPR), which was induced by ER stress, and mTORC1 in glomerular podocytes before the onset of proteinuria and downregulation of nephrin at the post-translational level at the onset of proteinuria. Podocyte culture experiments revealed that mTORC1 activation preceded the UPR that was associated with a marked decrease in the energy charge. The mTORC1 inhibitor everolimus completely inhibited proteinuria through a reduction in both mTORC1 and UPR activity and preserved nephrin expression in the glomerular podocytes. In conclusion, mTORC1 activation may perturb the regulatory system of energy metabolism primarily by promoting energy consumption and inducing the UPR, which underlie proteinuria in MCD.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Nefrose Lipoide/metabolismo , Podócitos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Animais , Western Blotting , Células Cultivadas , Everolimo , Imunofluorescência , Imuno-Histoquímica , Microscopia Confocal , Nefrose Lipoide/etiologia , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirolimo/análogos & derivados , Estatísticas não Paramétricas , Serina-Treonina Quinases TOR/antagonistas & inibidores
15.
Matrix Biol ; 97: 20-39, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33592276

RESUMO

Dupuytren's Disease (DD) is a common fibroproliferative disease of the palmar fascia. We previously identified a causal association with a non-synonymous variant (rs1042704, p.D273N) in MMP14 (encoding MT1-MMP). In this study, we investigated the functional consequences of this variant, and demonstrated that the variant MT1-MMP (MT1-N273) exhibits only 17% of cell surface collagenolytic activity compared to the ancestral enzyme (MT1-D273). Cells expressing both MT1-D273 and MT1-N273 in a 1:1 ratio, mimicking the heterozygous state, possess 38% of the collagenolytic activity compared to the cells expressing MT1-D273, suggesting that MT1-N273 acts in a dominant negative manner. Consistent with the above observation, patient-derived DD myofibroblasts with the alternate allele demonstrated around 30% of full collagenolytic activity detected in ancestral G/G genotype cells, regardless of the heterozygous (G/A) or homozygous (A/A) state. Small angle X-ray scattering analysis of purified soluble Fc-fusion enzymes allowed us to construct a 3D-molecular envelope of MT1-D273 and MT1-N273, and demonstrate altered flexibility and conformation of the ectodomains due to D273 to N substitution. Taking together, rs1042704 significantly reduces collagen catabolism in tissue, which tips the balance of homeostasis of collagen in tissue, contributing to the fibrotic phenotype of DD. Since around 30% of the worldwide population have at least one copy of the low collagenolytic alternate allele, further investigation of rs1042704 across multiple pathologies is needed.


Assuntos
Colágeno/metabolismo , Contratura de Dupuytren/genética , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Polimorfismo de Nucleotídeo Único , Animais , Células COS , Chlorocebus aethiops , Contratura de Dupuytren/metabolismo , Humanos , Metaloproteinase 14 da Matriz/química , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Espalhamento a Baixo Ângulo , Difração de Raios X
16.
J Am Soc Nephrol ; 20(7): 1586-96, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19443642

RESUMO

LAT3 is a Na+-independent neutral l-amino acid transporter recently isolated from a human hepatocellular carcinoma cell line. Although liver, skeletal muscle, and pancreas are known to express LAT3, the tissue distribution and physiologic function of this transporter are not completely understood. Here, we observed that glomeruli express LAT3. Immunofluorescence, confocal microscopy, and immunoelectron microscopy revealed that LAT3 localizes to the apical plasma membrane of podocyte foot processes. In mice, starvation upregulated glomerular LAT3, phosphorylated AKT1, reconstituted the actin network, and elongated foot processes. In the fetal kidney, we observed intense LAT3 expression at the capillary loops stage of renal development. Finally, zebrafish morphants lacking lat3 function showed collapsed glomeruli with thickened glomerular basement membranes. Permeability studies of the glomerular filtration barrier in these zebrafish morphants demonstrated a disruption of selective glomerular permeability. Our data suggest that LAT3 may play a crucial role in the development and maintenance of podocyte structure and function by regulating protein synthesis and the actin cytoskeleton.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Diferenciação Celular/fisiologia , Glomérulos Renais/metabolismo , Podócitos/metabolismo , Actinas/metabolismo , Sistemas de Transporte de Aminoácidos Básicos/genética , Animais , Membrana Celular/metabolismo , Citoesqueleto/metabolismo , Feminino , Membrana Basal Glomerular/metabolismo , Taxa de Filtração Glomerular/fisiologia , Humanos , Glomérulos Renais/citologia , Glomérulos Renais/embriologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosforilação , Podócitos/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
17.
Cell Rep ; 31(7): 107655, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32433964

RESUMO

Transcription factors (TFs) play a pivotal role in determining cell states, yet our understanding of the causative relationship between TFs and cell states is limited. Here, we systematically examine the state changes of human pluripotent embryonic stem cells (hESCs) by the large-scale manipulation of single TFs. We establish 2,135 hESC lines, representing three clones each of 714 doxycycline (Dox)-inducible genes including 481 TFs, and obtain 26,998 microscopic cell images and 2,174 transcriptome datasets-RNA sequencing (RNA-seq) or microarrays-48 h after the presence or absence of Dox. Interestingly, the expression of essentially all the genes, including genes located in heterochromatin regions, are perturbed by these TFs. TFs are also characterized by their ability to induce differentiation of hESCs into specific cell lineages. These analyses help to provide a way of classifying TFs and identifying specific sets of TFs for directing hESC differentiation into desired cell types.


Assuntos
Células-Tronco Embrionárias Humanas/metabolismo , Fatores de Transcrição/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Células-Tronco Embrionárias Humanas/citologia , Humanos , Análise de Célula Única/métodos
18.
Lab Invest ; 89(2): 178-95, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19079321

RESUMO

Nephrin is an essential structural component of the glomerular slit diaphragm (SD), a highly organized intercellular junction that constitutes the ultrafiltration barrier of the kidney. Recent studies have identified two additional nephrin-interacting SD proteins (NEPH1 and NEPH2), suggesting that the zipper-like pattern of the SD is formed through complex intra- and intermolecular interactions of these proteins. However, the complexity of the SD structure suggests that additional SD components remain to be discovered. In this study, we identified galectin-1 (Gal-1) as a new component of the SD, binding to the ectodomain of nephrin. Using dual-immunofluorescence and confocal microscopy and dual-immunoelectron microscopy, we found Gal-1 co-localizing with the ectodomain of nephrin at the SD in normal human kidney. By immunoprecipitation and surface plasmon resonance, we confirmed a direct molecular interaction between Gal-1 and nephrin. Moreover, recombinant Gal-1 induced tyrosine phosphorylation of the cytoplasmic domain of nephrin and activation of the extracellular signal-regulated kinase 1/2 in podocytes. We also showed that podocytes are a major site of biosynthesis of Gal-1 in the glomerulus and that the normal expression patterns and levels of Gal-1 are altered in patients with minimal change nephrotic syndrome. Finally, in puromycin aminonucleoside-induced rat nephrosis, an apparent reduction in the levels of Gal-1 and nephrin around the onset of heavy proteinuria was also revealed. Our data present Gal-1 as a new extracellular ligand of nephrin localized at the glomerular SD, and provide further insight into the complex molecular organization, interaction, and structure of the SD, which is an active site of intracellular signaling necessary for podocyte function.


Assuntos
Galectina 1/metabolismo , Rim/metabolismo , Nefrose Lipoide/metabolismo , Podócitos/metabolismo , Animais , Linhagem Celular Transformada , Modelos Animais de Doenças , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Galectina 1/farmacologia , Humanos , Rim/patologia , Proteínas de Membrana/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Proteína Quinase 3 Ativada por Mitógeno/biossíntese , Nefrose Lipoide/induzido quimicamente , Nefrose Lipoide/patologia , Fosforilação , Podócitos/efeitos dos fármacos , Podócitos/patologia , Ratos , Proteínas Recombinantes , Tirosina/metabolismo
19.
Mol Biol Cell ; 17(12): 5390-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17050733

RESUMO

Pericellular degradation of interstitial collagens is a crucial event for cells to migrate through the dense connective tissue matrices, where collagens exist as insoluble fibers. A key proteinase that participates in this process is considered to be membrane-type 1 matrix metalloproteinase (MT1-MMP or MMP-14), but little is known about the mechanism by which it cleaves the insoluble collagen. Here we report that homodimerization of MT1-MMP through its hemopexin (Hpx) domain is essential for cleaving type I collagen fibers at the cell surface. When dimerization was blocked by coexpressing either a membrane-bound or a soluble form of the Hpx domain, cell surface collagenolytic activity was inhibited in a dose-dependent manner. When MMP-13, a soluble collagenase active as a monomer in solution, was expressed as a membrane-anchored form on the cell surface, homodimerization was also required to cleave collagen. Our results introduce a new concept in that pericellular collagenolysis is regulated by correct molecular assembly of the membrane-anchored collagenase, thereby governing the directionality of the cell to migrate in tissue.


Assuntos
Membrana Celular/metabolismo , Colágeno Tipo I/metabolismo , Colagenases/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Proteínas de Membrana/metabolismo , Animais , Células COS , Chlorocebus aethiops , Dimerização , Cães , Géis , Humanos , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 14 da Matriz/química , Proteínas Mutantes/metabolismo , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo
20.
Kurume Med J ; 65(2): 71-75, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-30197407

RESUMO

In total hip arthroplasty (THA), it is generally accepted that the bones of the acetabular cup and femur of hip joint must be accurately cut and components (artificial joint parts) be implanted in exact positions at exact angles to achieve improvement of daily living (ADL) and quality of life (QOL). However, with the conventional surgical method, it is difficult to grasp and measure the acetabular cup and femoral stem precisely during surgery, making some kind of reliable guide necessary. Although it was reported that an accurate angle was achieved in acetabular cup implantation by support instruments for surgical planning, an effective support instrument is now being developed for stem implantation on the out-of-reach femur side. This is the first clinical study to assess the efficacy and safety of anterolateral approach THA using an extracorporeal patient-specific femoral guide (PSG) for stem implantation with three-dimensional (3D) surgical support software in patients with hip joint disease.


Assuntos
Artroplastia de Quadril/métodos , Imageamento Tridimensional/métodos , Software , Cirurgia Assistida por Computador/métodos , Acetábulo/cirurgia , Atividades Cotidianas , Adulto , Idoso , Feminino , Fêmur/cirurgia , Articulação do Quadril/cirurgia , Prótese de Quadril , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Qualidade de Vida , Reprodutibilidade dos Testes , Tamanho da Amostra
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA