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1.
Proc Natl Acad Sci U S A ; 120(14): e2221083120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36972446

RESUMEN

Phosphatases of regenerating liver (PRL-1, PRL-2, PRL-3; also known as PTP4A1, PTP4A2, PTP4A3, respectively) control intracellular magnesium levels by interacting with the CNNM magnesium transport regulators. Still, the exact mechanism governing magnesium transport by this protein complex is not well understood. Herein, we have developed a genetically encoded intracellular magnesium-specific reporter and demonstrate that the CNNM family inhibits the function of the TRPM7 magnesium channel. We show that the small GTPase ARL15 increases CNNM3/TRPM7 protein complex formation to reduce TRPM7 activity. Conversely, PRL-2 overexpression counteracts ARL15 binding to CNNM3 and enhances the function of TRPM7 by preventing the interaction between CNNM3 and TRPM7. Moreover, while TRPM7-induced cell signaling is promoted by PRL-1/2, it is reduced when CNNM3 is overexpressed. Lowering cellular magnesium levels reduces the interaction of CNNM3 with TRPM7 in a PRL-dependent manner, whereby knockdown of PRL-1/2 restores the protein complex formation. Cotargeting of TRPM7 and PRL-1/2 alters mitochondrial function and sensitizes cells to metabolic stress induced by magnesium depletion. These findings reveal the dynamic regulation of TRPM7 function in response to PRL-1/2 levels, to coordinate magnesium transport and reprogram cellular metabolism.


Asunto(s)
Magnesio , Canales Catiónicos TRPM , Magnesio/metabolismo , Canales Catiónicos TRPM/genética , Canales Catiónicos TRPM/metabolismo , Transducción de Señal , Metabolismo Energético
2.
Immunity ; 43(2): 277-88, 2015 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-26231120

RESUMEN

Plasmacytoid dendritic cells (pDCs) are primary producers of type I interferon (IFN) in response to viruses. The IFN-producing capacity of pDCs is regulated by specific inhibitory receptors, yet none of the known receptors are conserved in evolution. We report that within the human immune system, receptor protein tyrosine phosphatase sigma (PTPRS) is expressed specifically on pDCs. Surface PTPRS was rapidly downregulated after pDC activation, and only PTPRS(-) pDCs produced IFN-α. Antibody-mediated PTPRS crosslinking inhibited pDC activation, whereas PTPRS knockdown enhanced IFN response in a pDC cell line. Similarly, murine Ptprs and the homologous receptor phosphatase Ptprf were specifically co-expressed in murine pDCs. Haplodeficiency or DC-specific deletion of Ptprs on Ptprf-deficient background were associated with enhanced IFN response of pDCs, leukocyte infiltration in the intestine and mild colitis. Thus, PTPRS represents an evolutionarily conserved pDC-specific inhibitory receptor, and is required to prevent spontaneous IFN production and immune-mediated intestinal inflammation.


Asunto(s)
Colitis/inmunología , Células Dendríticas/inmunología , Intestinos/inmunología , Leucocitos/fisiología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Animales , Diferenciación Celular , Movimiento Celular/genética , Células Cultivadas , Colitis/genética , Modelos Animales de Enfermedad , Humanos , Interferón gamma/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/genética
3.
FASEB J ; 35(7): e21708, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34169549

RESUMEN

Metabolic reprogramming occurs in cancer cells and is regulated partly by the opposing actions of tyrosine kinases and tyrosine phosphatases. Several members of the protein tyrosine phosphatase (PTP) superfamily have been linked to cancer as either pro-oncogenic or tumor-suppressive enzymes. In order to investigate which PTPs can modulate the metabolic state of cancer cells, we performed an shRNA screen of PTPs in HCT116 human colorectal cancer cells. Among the 72 PTPs efficiently targeted, 24 were found to regulate mitochondrial respiration, 8 as negative and 16 as positive regulators. Of the latter, we selected TC-PTP (PTPN2) for further characterization since inhibition of this PTP resulted in major functional defects in oxidative metabolism without affecting glycolytic flux. Transmission electron microscopy revealed an increase in the number of damaged mitochondria in TC-PTP-null cells, demonstrating the potential role of this PTP in regulating mitochondrial homeostasis. Downregulation of STAT3 by siRNA-mediated silencing partially rescued the mitochondrial respiration defect observed in TC-PTP-deficient cells, supporting the role of this signaling axis in regulating mitochondrial activity. In addition, mitochondrial stress prevented an increased expression of electron transport chain-related genes in cells with TC-PTP silencing, correlating with decreased ATP production, cellular proliferation, and migration. Our shRNA-based metabolic screen revealed that PTPs can serve as either positive or negative regulators of cancer cell metabolism. Taken together, our findings uncover a new role for TC-PTP as an activator of mitochondrial metabolism, validating this PTP as a key target for cancer therapeutics.


Asunto(s)
Metabolismo Energético/fisiología , Dinámicas Mitocondriales/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 2/metabolismo , Tirosina/metabolismo , Línea Celular , Línea Celular Tumoral , Proliferación Celular/fisiología , Células HCT116 , Células HEK293 , Humanos , Fosforilación/fisiología , Proteínas Tirosina Quinasas/metabolismo , ARN Interferente Pequeño/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal/fisiología
4.
Cell Mol Life Sci ; 78(13): 5427-5445, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34089346

RESUMEN

Cyclin M (CNNM1-4) proteins maintain cellular and body magnesium (Mg2+) homeostasis. Using various biochemical approaches, we have identified members of the CNNM family as direct interacting partners of ADP-ribosylation factor-like GTPase 15 (ARL15), a small GTP-binding protein. ARL15 interacts with CNNMs at their carboxyl-terminal conserved cystathionine-ß-synthase (CBS) domains. In silico modeling of the interaction between CNNM2 and ARL15 supports that the small GTPase specifically binds the CBS1 and CNBH domains. Immunocytochemical experiments demonstrate that CNNM2 and ARL15 co-localize in the kidney, with both proteins showing subcellular localization in the endoplasmic reticulum, Golgi apparatus and the plasma membrane. Most importantly, we found that ARL15 is required for forming complex N-glycosylation of CNNMs. Overexpression of ARL15 promotes complex N-glycosylation of CNNM3. Mg2+ uptake experiments with a stable isotope demonstrate that there is a significant increase of 25Mg2+ uptake upon knockdown of ARL15 in multiple kidney cancer cell lines. Altogether, our results establish ARL15 as a novel negative regulator of Mg2+ transport by promoting the complex N-glycosylation of CNNMs.


Asunto(s)
Factores de Ribosilacion-ADP/metabolismo , Ciclinas/metabolismo , Homeostasis , Magnesio/metabolismo , Factores de Ribosilacion-ADP/genética , Transporte Biológico , Ciclinas/genética , Glicosilación , Células HEK293 , Humanos , Modelos Moleculares , Unión Proteica
5.
J Neurosci ; 37(30): 7125-7139, 2017 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-28637841

RESUMEN

Leukocyte common antigen-related (LAR) class protein tyrosine phosphatases (PTPs) are critical for axonal guidance; however, their relation to specific guidance cues is poorly defined. We here show that PTP-3, a LAR homolog in Caenorhabditis elegans, is involved in axon guidance regulated by Semaphorin-2A-signaling. PTPδ, one of the vertebrate LAR class PTPs, participates in the Semaphorin-3A (Sema3A)-induced growth cone collapse response of primary cultured dorsal root ganglion neurons from Mus musculus embryos. In vivo, however, the contribution of PTPδ in Sema3A-regualted axon guidance was minimal. Instead, PTPδ played a major role in Sema3A-dependent cortical dendritic growth. Ptpδ-/- and Sema3a-/- mutant mice exhibited poor arborization of basal dendrites of cortical layer V neurons. This phenotype was observed in both male and female mutants. The double-heterozygous mutants, Ptpδ+/-; Sema3a+/-, also showed a similar phenotype, indicating the genetic interaction. In Ptpδ-/- brains, Fyn and Src kinases were hyperphosphorylated at their C-terminal Tyr527 residues. Sema3A-stimulation induced dephosphorylation of Tyr527 in the dendrites of wild-type cortical neurons but not of Ptpδ-/- Arborization of cortical basal dendrites was reduced in Fyn-/- as well as in Ptpδ+/-; Fyn+/- double-heterozygous mutants. Collectively, PTPδ mediates Sema3A-signaling through the activation of Fyn by C-terminal dephosphorylation.SIGNIFICANCE STATEMENT The relation of leukocyte common antigen-related (LAR) class protein tyrosine phosphatases (PTPs) and specific axon guidance cues is poorly defined. We show that PTP-3, a LAR homolog in Caenorhabditis elegans, participates in Sema2A-regulated axon guidance. PTPδ, a member of vertebrate LAR class PTPs, is involved in Sema3A-regulated cortical dendritic growth. In Sema3A signaling, PTPδ activates Fyn and Src kinases by dephosphorylating their C-terminal Tyr residues. This is the first evidence showing that LAR class PTPs participate in Semaphorin signaling in vivo.


Asunto(s)
Corteza Cerebral/fisiología , Dendritas/fisiología , Plasticidad Neuronal/fisiología , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Semaforina-3A/metabolismo , Animales , Células Cultivadas , Corteza Cerebral/ultraestructura , Dendritas/ultraestructura , Activación Enzimática , Femenino , Regulación Enzimológica de la Expresión Génica/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas Tirosina Quinasas/metabolismo
6.
J Biol Chem ; 291(20): 10716-25, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-26969161

RESUMEN

The oncogenic phosphatase of regenerating liver 2 (PRL-2) has been shown to regulate intracellular magnesium levels by forming a complex through an extended amino acid loop present in the Bateman module of the CNNM3 magnesium transporter. Here we identified highly conserved residues located on this amino acid loop critical for the binding with PRL-2. A single point mutation (D426A) of one of those critical amino acids was found to completely disrupt PRL-2·human Cyclin M 3 (CNNM3) complex formation. Whole-cell voltage clamping revealed that expression of CNNM3 influenced the surface current, whereas overexpression of the binding mutant had no effect, indicating that the binding of PRL-2 to CNNM3 is important for the activity of the complex. Interestingly, overexpression of the CNNM3 D426A-binding mutant in cancer cells decreased their ability to proliferate under magnesium-deprived situations and under anchorage-independent growth conditions, demonstrating a PRL-2·CNNM3 complex-dependent oncogenic advantage in a more stringent environment. We further confirmed the importance of this complex in vivo using an orthotopic xenograft breast cancer model. Finally, because molecular modeling showed that the Asp-426 side chain in CNNM3 buries into the catalytic cavity of PRL-2, we showed that a PRL inhibitor could abrogate complex formation, resulting in a decrease in proliferation of human breast cancer cells. In summary, we provide evidence that this fundamental regulatory aspect of PRL-2 in cancer cells could potentially lead to broadly applicable and innovative therapeutic avenues.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/terapia , Ciclinas/antagonistas & inhibidores , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Secuencia Conservada , Ciclinas/química , Ciclinas/genética , Femenino , Humanos , Ratones , Ratones Desnudos , Modelos Moleculares , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación Puntual , Dominios y Motivos de Interacción de Proteínas/efectos de los fármacos , Proteínas Tirosina Fosfatasas/química , Proteínas Tirosina Fosfatasas/genética , Piridonas/farmacología , Ensayo de Tumor de Célula Madre , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Development ; 140(16): 3413-22, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23863482

RESUMEN

Leukocyte antigen related (LAR) family receptor protein tyrosine phosphatases (RPTPs) regulate the fine balance between tyrosine phosphorylation and dephosphorylation that is crucial for cell signaling during development and tissue homeostasis. Here we show that LAR RPTPs are required for normal development of the mandibular and maxillary regions. Approximately half of the mouse embryos lacking both Ptprs (RPTPσ) and Ptprf (LAR) exhibit micrognathia (small lower jaw), cleft palate and microglossia/glossoptosis (small and deep tongue), a phenotype closely resembling Pierre-Robin sequence in humans. We show that jaw bone and cartilage patterning occurs aberrantly in LAR family phosphatase-deficient embryos and that the mandibular arch harbors a marked decrease in cell proliferation. Analysis of signal transduction in embryonic tissues and mouse embryonic fibroblast cultures identifies an increase in Bmp-Smad signaling and an abrogation of canonical Wnt signaling associated with loss of the LAR family phosphatases. A reactivation of ß-catenin signaling by chemical inhibition of GSK3ß successfully resensitizes LAR family phosphatase-deficient cells to Wnt induction, indicating that RPTPs are necessary for normal Wnt/ß-catenin pathway activation. Together these results identify LAR RPTPs as important regulators of craniofacial morphogenesis and provide insight into the etiology of Pierre-Robin sequence.


Asunto(s)
Silenciador del Gen , Síndrome de Pierre Robin/enzimología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Animales , Proteína Axina/genética , Proteína Axina/metabolismo , Tipificación del Cuerpo , Desarrollo Óseo , Proliferación Celular , Células Cultivadas , Fisura del Paladar/enzimología , Fisura del Paladar/patología , Embrión de Mamíferos/enzimología , Embrión de Mamíferos/patología , Fibroblastos/enzimología , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta , Indoles/farmacología , Mesodermo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Micrognatismo/enzimología , Micrognatismo/patología , Oximas/farmacología , Síndrome de Pierre Robin/patología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/genética , Vía de Señalización Wnt
8.
Histochem Cell Biol ; 146(1): 99-111, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27015884

RESUMEN

The phosphatase of regenerating liver (PRL) is a group of protein tyrosine phosphatases that play a key role in cancer progression and metastasis. We previously showed that PRL-2 modulates intracellular Mg(2+) levels and sustains cancer phenotypes by binding to the Mg(2+) transporter CNNM3. However, the physiological functions of PRL-2 in animals remain largely unknown. To better understand which cell types are associated with PRL-2 function, we characterized its expression in mouse tissues using a PRL-2 ß-galactosidase reporter mouse model. Our results demonstrated that PRL-2 was ubiquitously expressed, with the highest expression levels observed in the hippocampal pyramidal neurons, ependymal cells, cone and rod photoreceptor cells, endocardium, vascular and bronchial smooth muscle, and collecting ducts in the kidney. On the other hand, PRL-2 expression was undetectable or very low in the parenchymal cells of the liver and pancreas. Our results also indicated that PRL-2 is involved in cell-type-specific Mg(2+) homeostasis and that PRL-2 expression is potentially inversely regulated by dietary Mg(2+) levels.


Asunto(s)
Suplementos Dietéticos , Proteínas Inmediatas-Precoces/análisis , Proteínas Inmediatas-Precoces/biosíntesis , Magnesio/farmacología , Proteínas Tirosina Fosfatasas/análisis , Proteínas Tirosina Fosfatasas/biosíntesis , Animales , Femenino , Homeostasis/efectos de los fármacos , Proteínas Inmediatas-Precoces/metabolismo , Magnesio/administración & dosificación , Magnesio/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Tirosina Fosfatasas/metabolismo
9.
Crit Rev Biochem Mol Biol ; 48(5): 430-45, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23879520

RESUMEN

Our understanding of the fundamental regulatory roles that tyrosine phosphatases play within cells has advanced significantly in the last two decades. Out-dated ideas that tyrosine phosphatases acts solely as the "off" switch counterbalancing the action of tyrosine kinases has proved to be flawed. PTP1B is the most characterized of all the tyrosine phosphatases and it acts as a critical negative and positive regulator of numerous signaling cascades. PTP1B's direct regulation of the insulin and the leptin receptors makes it an ideal therapeutic target for type II diabetes and obesity. Moreover, the last decade has also seen several reports establishing PTP1B as key player in cancer serving as both tumor suppressor and tumor promoter depending on the cellular context. Despite many key advances in these fields one largely ignored area is what role PTP1B may play in the modulation of immune signaling. The important recognition that PTP1B is a major negative regulator of Janus kinase - signal transducer and activator of transcription (JAK-STAT) signaling throughout evolution places it as a key link between metabolic diseases and inflammation, as well as a unique regulator between immune response and cancer. This review looks at the emergence of PTP1B through evolution, and then explore at the cell and systemic levels how it is controlled physiologically. The second half of the review will focus on the role(s) PTP1B can play in disease and in particular its involvement in metabolic syndromes and cancer. Finally we will briefly examine several novel directions in the development of PTP1B pharmacological inhibitors.


Asunto(s)
Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Animales , Enfermedad , Inhibidores Enzimáticos/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 1/genética , Especificidad por Sustrato/efectos de los fármacos
10.
Mol Med ; 21(1): 717-725, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26181631

RESUMEN

The receptor type protein tyrosine phosphatase D (PTPRD) gene encodes a cell adhesion molecule likely to influence development and connections of addiction-, locomotion- and sleep-related brain circuits in which it is expressed. The PTPRD gene harbors genome-wide association signals in studies of restless leg syndrome (Willis-Ekbom disease [WED]/restless leg syndrome [RLS]; p < 10-8) and addiction-related phenotypes (clusters of nearby single nucleotide polymorphisms [SNPs] with 10-2 > p > 10-8 associations in several reports). We now report work that seeks (a) association between PTPRD genotypes and expression of its mRNA in postmortem human brains and (b) RLS-related, addiction-related and comparison behavioral phenotypes in hetero- and homozygous PTPRD knockout mice. We identify associations between PTPRD SNPs and levels of PTPRD mRNA in human brain samples that support validity of mouse models with altered PTPRD expression. Knockouts display less behaviorally defined sleep at the end of their active periods. Heterozygotes move more despite motor weakness/impersistence. Heterozygotes display shifted dose-response relationships for cocaine reward. They display greater preference for places paired with 5 mg/kg cocaine and less preference for places paired with 10 or 20 mg/kg. The combined data provide support for roles for common, level-of-expression PTPRD variation in locomotor, sleep and drug reward phenotypes relevant to RLS and addiction. Taken together, mouse and human results identify PTPRD as a novel therapeutic target for RLS and addiction phenotypes.

11.
Proc Natl Acad Sci U S A ; 109(13): 4768-73, 2012 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-22411830

RESUMEN

Chondroitin sulfate proteoglycans (CSPGs) represent a major barrier to regenerating axons in the central nervous system (CNS), but the structural diversity of their polysaccharides has hampered efforts to dissect the structure-activity relationships underlying their physiological activity. By taking advantage of our ability to chemically synthesize specific oligosaccharides, we demonstrate that a sugar epitope on CSPGs, chondroitin sulfate-E (CS-E), potently inhibits axon growth. Removal of the CS-E motif significantly attenuates the inhibitory activity of CSPGs on axon growth. Furthermore, CS-E functions as a protein recognition element to engage receptors including the transmembrane protein tyrosine phosphatase PTPσ, thereby triggering downstream pathways that inhibit axon growth. Finally, masking the CS-E motif using a CS-E-specific antibody reversed the inhibitory activity of CSPGs and stimulated axon regeneration in vivo. These results demonstrate that a specific sugar epitope within chondroitin sulfate polysaccharides can direct important physiological processes and provide new therapeutic strategies to regenerate axons after CNS injury.


Asunto(s)
Axones/patología , Axones/fisiología , Proteoglicanos Tipo Condroitín Sulfato/inmunología , Epítopos/inmunología , Regeneración Nerviosa/fisiología , Animales , Anticuerpos Bloqueadores/farmacología , Anticuerpos Monoclonales/farmacología , Anticuerpos Neutralizantes/farmacología , Axones/efectos de los fármacos , Conformación de Carbohidratos , Pollos , Proteoglicanos Tipo Condroitín Sulfato/química , Sulfatos de Condroitina/química , Sulfatos de Condroitina/inmunología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Conos de Crecimiento/efectos de los fármacos , Conos de Crecimiento/metabolismo , Conos de Crecimiento/patología , Ratones , Neuritas/enzimología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Transducción de Señal/efectos de los fármacos
12.
J Neurochem ; 122(1): 147-61, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22519304

RESUMEN

The mechanisms that regulate synapse formation and maintenance are incompletely understood. In particular, relatively few inhibitors of synapse formation have been identified. Receptor protein tyrosine phosphatase σ (RPTPσ), a transmembrane tyrosine phosphatase, is widely expressed by neurons in developing and mature mammalian brain, and functions as a receptor for chondroitin sulfate proteoglycans that inhibits axon regeneration following injury. In this study, we address RPTPσ function in the mature brain. We demonstrate increased axon collateral branching in the hippocampus of RPTPσ null mice during normal aging or following chemically induced seizure, indicating that RPTPσ maintains neural circuitry by inhibiting axonal branching. Previous studies demonstrated a role for pre-synaptic RPTPσ promoting synaptic differentiation during development; however, subcellular fractionation revealed enrichment of RPTPσ in post-synaptic densities. We report that neurons lacking RPTPσ have an increased density of pre-synaptic varicosities in vitro and increased dendritic spine density and length in vivo. RPTPσ knockouts exhibit an increased frequency of miniature excitatory post-synaptic currents, and greater paired-pulse facilitation, consistent with increased synapse density but reduced synaptic efficiency. Furthermore, RPTPσ nulls exhibit reduced long-term potentiation and enhanced novel object recognition memory. We conclude that RPTPσ limits synapse number and regulates synapse structure and function in the mature CNS.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Potenciación a Largo Plazo/genética , Neuronas/citología , Densidad Postsináptica/genética , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Reconocimiento en Psicología/fisiología , Factores de Edad , Análisis de Varianza , Animales , Animales Recién Nacidos , Axones/efectos de los fármacos , Axones/patología , Axones/ultraestructura , Células Cultivadas , Corteza Cerebral/citología , Modelos Animales de Enfermedad , Estimulación Eléctrica , Embrión de Mamíferos , Agonistas de Aminoácidos Excitadores/toxicidad , Ácido Kaínico/toxicidad , Potenciación a Largo Plazo/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Fibras Musgosas del Hipocampo/fisiología , Neuronas/efectos de los fármacos , Pruebas Neuropsicológicas , Técnicas de Placa-Clamp , Densidad Postsináptica/efectos de los fármacos , Ratas , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/deficiencia , Reconocimiento en Psicología/efectos de los fármacos , Tinción con Nitrato de Plata , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genética , Estado Epiléptico/patología
13.
Commun Biol ; 3(1): 603, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097786

RESUMEN

Protein tyrosine phosphatases are essential modulators of angiogenesis and have been identified as novel therapeutic targets in cancer and anti-angiogenesis. The roles of atypical Phosphatase of Regenerative Liver (PRL) phosphatases in this context remain poorly understood. Here, we investigate the biological function of PRL phosphatases in developmental angiogenesis in the postnatal mouse retina and in cell culture. We show that endothelial cells in the retina express PRL-2 encoded by the Ptp4a2 gene, and that inducible endothelial and global Ptp4a2 mutant mice exhibit defective retinal vascular outgrowth, arteriovenous differentiation, and sprouting angiogenesis. Mechanistically, PTP4A2 deletion limits angiogenesis by inhibiting endothelial cell migration and the VEGF-A, DLL-4/NOTCH-1 signaling pathway. This study reveals the importance of PRL-2 as a modulator of vascular development.


Asunto(s)
Proteínas Inmediatas-Precoces , Neovascularización Fisiológica/genética , Proteínas Tirosina Fosfatasas , Transducción de Señal/genética , Animales , Movimiento Celular/genética , Células Cultivadas , Células Endoteliales/citología , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Proteínas Inmediatas-Precoces/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Fosfatasas/fisiología , Retina/citología , Retina/metabolismo , Malformaciones Vasculares/genética , Malformaciones Vasculares/patología
14.
Dev Cell ; 2(4): 497-503, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11970899

RESUMEN

Common obesity is primarily characterized by resistance to the actions of the hormone leptin. Mice deficient in protein tyrosine phosphatase 1B (PTP1B) are resistant to diabetes and diet-induced obesity, prompting us to further define the relationship between PTP1B and leptin in modulating obesity. Leptin-deficient (Lep(ob/ob)) mice lacking PTP1B exhibit an attenuated weight gain, a decrease in adipose tissue, and an increase in resting metabolic rate. Furthermore, PTP1B-deficient mice show an enhanced response toward leptin-mediated weight loss and suppression of feeding. Hypothalami from these mice also display markedly increased leptin-induced Stat3 phosphorylation. Finally, substrate-trapping experiments demonstrate that leptin-activated Jak2, but not Stat3 or the leptin receptor, is a substrate of PTP1B. These results suggest that PTP1B negatively regulates leptin signaling, and provide one mechanism by which it may regulate obesity.


Asunto(s)
Leptina/metabolismo , Obesidad/genética , Obesidad/metabolismo , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas , Animales , Proteínas de Unión al ADN/metabolismo , Genotipo , Hipotálamo/fisiología , Janus Quinasa 2 , Leptina/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Mutantes , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteínas Tirosina Quinasas/metabolismo , Factor de Transcripción STAT3 , Transactivadores/metabolismo , Aumento de Peso
15.
Brain Res ; 1211: 57-71, 2008 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-18423429

RESUMEN

The transcription factor FosB is induced in neurons of the medial preoptic area (MPOA) during parenting, through activation of the extracellular signal-regulated kinase (ERK). FosB mutant (-/-) postpartum mice and virgin mice that are exposed to pups show defective nurturing behavior. The FosB (-/-) MPOA fails to fully up-regulate SPRY1 and Rad, the feedback regulators of ERK and calcium signaling, respectively. Here we studied FosB function by examining the gene expression profiles and the behavioral characteristics of FosB (-/-) mice. We found that FosB (-/|-) mice exhibited not only decreased parenting but also decreased infanticide compared with (+/) littermates. We then performed gene expression analysis in the MPOA of FosB (-/-) mice compared with the wild-type littermates. We found up-regulation of glial fibrillary acidic protein (GFAP), C4, and Ela1 mRNA in the MPOA of FosB (-/-) mice; all of these gene products were implicated in general neuropathological conditions. Immunohistochemical analysis showed that up-regulation of GFAP was not restricted to MPOA but extended throughout the forebrain, including the cerebral cortex and striatum. Such pervasive GFAP up-regulation suggested that FosB (-/-) mice might have other behavioral abnormalities than nurturing. Indeed, these mice showed a clear alteration in emotionality, detected by the acoustic startle, elevated plus maze, and passive avoidance tests. These results suggest that FosB (-/-) mice have broader neurobehavioral dysfunctions, with which the nurturing defect might share the common mechanism.


Asunto(s)
Genes fos/genética , Conducta Materna/fisiología , Área Preóptica/fisiología , Proteínas Proto-Oncogénicas c-fos/genética , Animales , Reacción de Prevención/fisiología , Conducta Animal/fisiología , Femenino , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Hidrocortisona/sangre , Masculino , Ratones , Ratones Noqueados , Actividad Motora/fisiología , Sistemas Neurosecretores/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , Reflejo de Sobresalto/genética , Reflejo de Sobresalto/fisiología , Restricción Física , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estrés Psicológico/genética , Estrés Psicológico/fisiopatología , Regulación hacia Arriba/genética , Regulación hacia Arriba/fisiología
16.
FEBS J ; 285(21): 3886-3908, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29770564

RESUMEN

The human Phosphatase of Regenerative Liver (PRL) family comprises three members (PRL-1, -2, -3; gene name PTP4A1, PTP4A2, PTP4A3) that are highly expressed in a majority of cancers. This review summarizes our current understanding of PRL biology, including an overview of their evolutionary relationships and the regulatory mechanisms controlling their expression. We provide an updated view on our current knowledge on the PRL functions in solid tumors, hematological cancer, and normal physiology, particularly emphasizing on the use of in vivo mouse models. We also highlight a novel relationship positioning PRL as a central node controlling magnesium homeostasis through an association with the CNNM proteins, which are involved in magnesium transport.


Asunto(s)
Homeostasis , Regeneración Hepática , Neoplasias/enzimología , Neoplasias/patología , Oncogenes , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo
17.
J Neurosci ; 26(22): 5872-80, 2006 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-16738228

RESUMEN

The leukocyte common antigen-related (LAR) subfamily of receptor protein tyrosine phosphatases (RPTPs), LAR, RPTP-sigma, and RPTP-delta, regulate neuroendocrine development, axonal regeneration, and hippocampal long-term potentiation in mammals. In Drosophila, RPTPs are required for appropriate axon targeting during embryonic development. In contrast, deletion of any one of the three LAR-RPTP family members in mammals does not result in gross axon targeting defects. Both RPTP-sigma and RPTP-delta are highly expressed in the developing mammalian nervous system, suggesting they might be functionally redundant. To test this hypothesis, we generated RPTP-sigma and RPTP-delta (RPTP-sigma/delta) double-mutant mice. Although embryonic day 18.5 RPTP-sigma and RPTP-delta single-mutant embryos were viable, RPTP-sigma/delta double mutants were paralyzed, were never observed to draw a breath, and died shortly after cesarean section. RPTP-sigma/delta double mutants exhibit severe muscle dysgenesis and severe loss of motoneurons in the spinal cord. Detailed analysis of the projections of phrenic nerves in RPTP-sigma/delta double mutants indicated that these motoneuron axons emerge normally from the cervical spinal cord, but stall on reaching the diaphragm. Our results demonstrate that RPTP-sigma and RPTP-delta complement each other functionally during mammalian development, and reveal an essential contribution of RPTP-sigma and RPTP-delta to appropriate motoneuron axon targeting during mammalian axonogenesis.


Asunto(s)
Axones/fisiología , Desarrollo Embrionario/fisiología , Neuronas Motoras/fisiología , Proteínas Tirosina Fosfatasas/deficiencia , Animales , Animales Recién Nacidos , Axones/enzimología , Muerte , Desarrollo Embrionario/genética , Miembro Anterior/embriología , Genotipo , Ratones , Ratones Noqueados/embriología , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores , Médula Espinal/embriología , Médula Espinal/enzimología
18.
Mech Dev ; 123(12): 869-80, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17070019

RESUMEN

PTP (protein-tyrosine phosphatase)-PEST is a ubiquitously expressed cellular regulator of integrin signalling. It has been shown to bind several molecules such as Shc, paxillin and Grb2, that are involved downstream of FAK (focal adhesion kinase) pathway. Through its specific association to p130cas and further dephosphorylation, PTP-PEST plays a critical role in cell-matrix interactions, which are essential during embryogenesis. We report here that ablation of the gene leads to early embryonic lethality, correlating well with the high expression of the protein during embryonic development. We observed an increased level of tyrosine phosphorylation of p130cas protein in E9.5 PTP-PEST(-/-) embryos, a first evidence of biochemical defect leading to abnormal growth and development. Analysis of null mutant embryos revealed that they reach gastrulation, initiate yolk sac formation, but fail to progress through normal subsequent developmental events. E9.5-10.5 PTP-PEST(-/-) embryos had morphological abnormalities such as defective embryo turning, improper somitogenesis and vasculogenesis, impaired liver development, accompanied by degeneration in both neuroepithelium and somatic epithelia. Moreover, in embryos surviving until E10.5, the caudal region was truncated, with severe mesenchyme deficiency and no successful liver formation. Defects in embryonic mesenchyme as well as subsequent failure of proper vascularization, liver development and somatogenesis, seemed likely to induce lethality at this stage of development, and these results confirm that PTP-PEST plays an essential function in early embryogenesis.


Asunto(s)
Vasos Sanguíneos/embriología , Embrión de Mamíferos/irrigación sanguínea , Genes Letales , Hígado/embriología , Sistema Nervioso/embriología , Proteínas Tirosina Fosfatasas/fisiología , Albúminas/genética , Albúminas/metabolismo , Animales , Aorta/citología , Vasos Sanguíneos/enzimología , Embrión de Mamíferos/anomalías , Embrión de Mamíferos/enzimología , Desarrollo Embrionario/genética , Células Endoteliales/citología , Hígado/anomalías , Hígado/enzimología , Mesodermo/citología , Mesodermo/enzimología , Ratones , Ratones Mutantes , Sistema Nervioso/enzimología , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 12 , Proteínas Tirosina Fosfatasas/análisis , Proteínas Tirosina Fosfatasas/genética , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Tirosina/metabolismo , Saco Vitelino/irrigación sanguínea , Saco Vitelino/citología
19.
JCI Insight ; 2(13)2017 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-28679948

RESUMEN

Magnesium (Mg2+) plays pleiotropic roles in cellular biology, and it is essentially required for all living organisms. Although previous studies demonstrated intracellular Mg2+ levels were regulated by the complex of phosphatase of regenerating liver 2 (PRL2) and Mg2+ transporter of cyclin M (CNNMs), physiological functions of PRL2 in whole animals remain unclear. Interestingly, Mg2+ was recently identified as a regulator of circadian rhythm-dependent metabolism; however, no mechanism was found to explain the clock-dependent Mg2+ oscillation. Herein, we report PRL2 as a missing link between sex and metabolism, as well as clock genes and daily cycles of Mg2+ fluxes. Our results unveil that PRL2-null animals displayed sex-dependent alterations in body composition, and expression of PRLs and CNNMs were sex- and circadian time-dependently regulated in brown adipose tissues. Consistently, PRL2-KO mice showed sex-dependent alterations in thermogenesis and in circadian energy metabolism. These physiological changes were associated with an increased rate of uncoupled respiration with lower intracellular Mg2+ in PRL2-KO cells. Moreover, PRL2 deficiency causes inhibition of the ATP citrate lyase axis, which is involved in fatty acid synthesis. Overall, our findings support that sex- and circadian-dependent PRL2 expression alter intracellular Mg2+ levels, which accordingly controls energy metabolism status.

20.
Brain Res ; 1642: 244-254, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27026654

RESUMEN

Protein tyrosine phosphate δ (PTPδ), one of the receptor type IIa protein tyrosine phosphates, is known for its roles in axon guidance, synapse formation, cell adhesion, and tumor suppression. Alternative splicing of this gene generates at least four (A-D) isoforms; however, the major isoform in vivo is yet to be determined. The protein localization has neither been revealed. We have generated anti-mouse PTPδ-specific monoclonal antibody and analyzed the protein expression in wild-type and Ptpδ knockout mice. Immunoblot analysis of various organs revealed that neuronal tissues express both C-and D-isoforms of PTPδ, whereas non-neuronal tissues express only C-isoform. Immunohistochemistry of wild-type or Ptpδ heterozygous sections showed that olfactory bulb, cerebral cortex, hippocampus, cerebellum, and several nuclei in brain stem exhibit moderate to strong positive signals. These signals were absent in Ptpδ knockout specimens. Higher magnification revealed differences between expression patterns of PTPδ mRNA and its protein product. In hippocampus, weak mRNA expression in CA1 stratum pyramidale but strong immunostaining in the stratum lacunosum moleculare was observed, suggesting the axonal expression of PTPδ in the entorhinal cortical afferents. Olfactory mitral cells exhibited mRNA expression in cell bodies and protein localization in their dendritic fields, glomerular and external plexiform layers. Nissl staining showed that the external plexiform layer was reduced in Ptpδ knockout mice. Golgi-impregnation confirmed the poor dendritic growth of homozygous mitral cells. These results suggest that PTPδ may localize in axons as well as in dendrites to regulate their elaboration in the central nervous system.


Asunto(s)
Encéfalo/enzimología , Neuronas/enzimología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Animales , Anticuerpos Monoclonales/administración & dosificación , Encéfalo/inmunología , Dendritas/enzimología , Isoenzimas/metabolismo , Masculino , Ratones , Ratones Noqueados , Bulbo Olfatorio/citología , Bulbo Olfatorio/enzimología , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/genética , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/inmunología
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