Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 744
Filtrar
1.
Adv Exp Med Biol ; 1131: 93-129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646508

RESUMO

Plasma membrane Ca2+ transport ATPases (PMCA1-4, ATP2B1-4) are responsible for removing excess Ca2+ from the cell in order to keep the cytosolic Ca2+ ion concentration at the low level essential for normal cell function. While these pumps take care of cellular Ca2+ homeostasis they also change the duration and amplitude of the Ca2+ signal and can create Ca2+ gradients across the cell. This is accomplished by generating more than twenty PMCA variants each having the character - fast or slow response, long or short memory, distinct interaction partners and localization signals - that meets the specific needs of the particular cell-type in which they are expressed. It has become apparent that these pumps are essential to normal tissue development and their malfunctioning can be linked to different pathological conditions such as certain types of neurodegenerative and heart diseases, hearing loss and cancer. In this chapter we summarize the complexity of PMCA regulation and function under normal and pathological conditions with particular attention to recent developments of the field.


Assuntos
Membrana Celular , ATPases Transportadoras de Cálcio da Membrana Plasmática , Animais , Membrana Celular/enzimologia , Membrana Celular/patologia , Citosol/metabolismo , Homeostase/fisiologia , Humanos , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo
2.
J Physiol Pharmacol ; 70(1)2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31172971

RESUMO

Dexamethasone inhibits mucin secretion considering the primary option for treating acute asthma exacerbation. However, the mechanism underlying dexamethasone-induced decreased in mucosecretion is unclear. Recent studies have reported that dexamethasone exerts an inhibitory effect on mucosecretion in the lung by modulating the expression of calcium processing genes. However, the expression of the calcium processing genes in the trachea is not examined yet. Thus, the present study is the first to report the localization of calcium processing proteins such as transient receptor potential vanilloid-4 (Trpv4), transient receptor potential vanilloid-6 (Trpv6), calbindin-D9k (CaBP-9k) and plasma membrane Ca2+-ATPase 1 (Pmca1) in the mouse trachea and their glucocorticoid-induced response. In this study, mice were subcutaneously injected with dexamethasone for 5 days, and their tracheal samples were collected by dividing the trachea into the cervical, and thoracic sections based on its anatomical structure. The localization of TRPV4, TRPV6, CaBP-9k, and PMCA1 proteins was detected in the tracheal epithelium, submucosal glands, cartilages and muscles. Dexamethasone treatment downregulated the mRNA expression of the four calcium processing genes and mucin producing genes. The dexamethasone-induced decrease in the secretion of mucosubstances in the trachea was determined by performing Alcian blue-periodic acid-Schiff staining. Thus, the findings of the present study suggest that glucocorticoids simultaneously can regulate the expression of calcium processing genes and tracheal mucosecretion.


Assuntos
Dexametasona/farmacologia , Glucocorticoides/farmacologia , Mucosa Respiratória/efeitos dos fármacos , Animais , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Feminino , Masculino , Camundongos Endogâmicos C57BL , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Mucosa Respiratória/metabolismo , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Traqueia/efeitos dos fármacos , Traqueia/metabolismo
3.
Biomed Res Int ; 2019: 9616248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31032369

RESUMO

Background: Plasma membrane Ca2+-ATPase (PMCA) is the most sensitive cellular calcium detector. It exists in four main isoforms (PMCA1-4), among which PMCA2 and PMCA3 are considered as fast-acting neuron-specific forms. In the brain, PMCA function declines progressively during aging; thereby impaired calcium homeostasis may contribute to some neurodegenerative diseases. These destructive processes can be propagated by proinflammatory chemokines, including chemokine CCL5, which causes phospholipase C-mediated liberation of Ca2+ from endoplasmic reticulum by IP3-gated channels. Methods: To mimic the changes in aged neurons we used stable transfected differentiated PC12 cells with downregulated PMCA2 or PMCA3 and analyzed the effect of CCL5 on calcium transients with Fluo-4 reagent. Chemokine receptors were evaluated using Western blot, and IP3 receptors expression level was assessed using qRT-PCR and Western blot. Results: In PMCA-reduced cell lines, CCL5 released more Ca2+ by IP3-sensitive receptors, and the time required for Ca2+ clearance was significantly longer. Also, in these lines we detected altered expression level of CCR5 and IP3 receptors. Conclusion: Although modification of PMCAs composition could provide some protection against calcium overload, reduction of PMCA2 appeared to be more detrimental to the cells than deficiency of PMCA3. Under pathological conditions, including inflammatory CCL5 action and long-lasting Ca2+ dyshomeostasis, insufficient cell protection may result in progressive degeneration and death of neurons.


Assuntos
Encéfalo/metabolismo , Quimiocina CCL5/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Compostos de Anilina/farmacologia , Animais , Encéfalo/patologia , Cálcio/metabolismo , Sinalização do Cálcio/genética , Morte Celular/genética , Diferenciação Celular/genética , Membrana Celular/genética , Homeostase/genética , Humanos , Neurônios/metabolismo , Células PC12 , Ratos , Transdução de Sinais/efeitos dos fármacos , Xantenos/farmacologia
4.
PLoS Genet ; 15(3): e1008027, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30849090

RESUMO

Populations in sub-Saharan Africa have historically been exposed to intense selection from chronic infection with falciparum malaria. Interestingly, populations with the highest malaria intensity can be identified by the increased occurrence of endemic Burkitt Lymphoma (eBL), a pediatric cancer that affects populations with intense malaria exposure, in the so called "eBL belt" in sub-Saharan Africa. However, the effects of intense malaria exposure and sub-Saharan populations' genetic histories remain poorly explored. To determine if historical migrations and intense malaria exposure have shaped the genetic composition of the eBL belt populations, we genotyped ~4.3 million SNPs in 1,708 individuals from Ghana and Northern Uganda, located on opposite sides of eBL belt and with ≥ 7 months/year of intense malaria exposure and published evidence of high incidence of BL. Among 35 Ghanaian tribes, we showed a predominantly West-Central African ancestry and genomic footprints of gene flow from Gambian and East African populations. In Uganda, the North West population showed a predominantly Nilotic ancestry, and the North Central population was a mixture of Nilotic and Southern Bantu ancestry, while the Southwest Ugandan population showed a predominant Southern Bantu ancestry. Our results support the hypothesis of diverse ancestral origins of the Ugandan, Kenyan and Tanzanian Great Lakes African populations, reflecting a confluence of Nilotic, Cushitic and Bantu migrations in the last 3000 years. Natural selection analyses suggest, for the first time, a strong positive selection signal in the ATP2B4 gene (rs10900588) in Northern Ugandan populations. These findings provide important baseline genomic data to facilitate disease association studies, including of eBL, in eBL belt populations.


Assuntos
Linfoma de Burkitt/genética , Fluxo Gênico , Malária Falciparum/genética , Seleção Genética , Adolescente , África ao Sul do Saara , Idoso , Linfoma de Burkitt/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Doenças Endêmicas , Feminino , Genética Populacional , Estudo de Associação Genômica Ampla , Gana/epidemiologia , Migração Humana , Humanos , Incidência , Lactente , Recém-Nascido , Malária Falciparum/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Polimorfismo de Nucleotídeo Único , Uganda/epidemiologia
5.
mSphere ; 4(1)2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728284

RESUMO

Calcium is a critically important secondary messenger of intracellular signal transduction in eukaryotes but must be maintained at low levels in the cytoplasm of resting cells to avoid toxicity. This is achieved by several pumps that actively transport excess cytoplasmic Ca2+ out of the cell across the plasma membrane and into other intracellular compartments. In fungi, the vacuole serves as the major storage site for excess Ca2+, with two systems actively transporting cytoplasmic calcium ions into the vacuole. The H+/Ca2+ exchanger, Vcx1p, harnesses the proton-motive force across the vacuolar membrane (generated by the V-ATPase) to drive Ca2+ transport, while the P-type ATPase Pmc1p uses ATP hydrolysis to translocate Ca2+ into the vacuole. Ca2+-dependent signaling is required for the prevalent human fungal pathogen Candida albicans to endure exposure to the azole antifungals and to cause disease within the mammalian host. The purpose of this study was to determine if the Pmc1p or Vcx1p Ca2+ pumps are required for C. albicans pathogenicity and if these pumps impact antifungal resistance. Our results indicate that Pmc1p is required by C. albicans to transition from yeast to hyphal growth, to form biofilms in vitro, and to cause disease in a mouse model of disseminated infection. Moreover, loss of Pmc1p function appears to enhance C. albicans azole tolerance in a temperature-dependent manner.IMPORTANCE Maintenance of Ca2+ homeostasis is important for fungal cells to respond to a multitude of stresses, as well as antifungal treatment, and for virulence in animal models. Here, we demonstrate that a P-type ATPase, Pmc1p, is required for Candida albicans to respond to a variety of stresses, affects azole susceptibility, and is required to sustain tissue invasive hyphal growth and to cause disease in a mouse model of disseminated infection. Defining the mechanisms responsible for maintaining proper Ca2+ homeostasis in this important human pathogen can ultimately provide opportunities to devise new chemotherapeutic interventions that dysregulate intracellular signaling and induce Ca2+ toxicity.


Assuntos
Candida albicans/genética , Candida albicans/patogenicidade , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Animais , Antifúngicos/farmacologia , Azóis/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candidíase Invasiva/microbiologia , Farmacorresistência Fúngica , Proteínas Fúngicas , Hifas/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Temperatura Ambiente , ATPases Vacuolares Próton-Translocadoras/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Virulência
6.
Cell Commun Signal ; 17(1): 7, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665402

RESUMO

Through a genome-wide screen we have identified calcium-tolerant deletion mutants for five genes in the budding yeast Saccharomyces cerevisiae. In addition to CNB1 and RCN1 that are known to play a role in the calcium signalling pathway, the protein kinase gene CMK2, the sphingolipid homeostasis-related gene ORM2 and the gene SIF2 encoding the WD40 repeat-containing subunit of Set3C histone deacetylase complex are involved in the calcium sensitivity of yeast cells to extracellular calcium. Cmk2 and the transcription factor Crz1 have opposite functions in the response of yeast cells to calcium stress. Deletion of CMK2 elevates the level of calcium/calcineurin signalling and increases the expression level of PMR1 and PMC1, which is dependent on Crz1. Effects of Cmk2 on calcium sensitivity and calcium/calcineurin signalling are dependent on its kinase activity. Therefore, Cmk2 is a negative feedback controller of the calcium/calcineurin signalling pathway. Furthermore, the cmk2 crz1 double deletion mutant is more resistant than the crz1 deletion mutant, suggesting that Cmk2 has an additional Crz1-independent role in promoting calcium tolerance.


Assuntos
Calcineurina/metabolismo , Cálcio/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Biocatálise , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , ATPases Transportadoras de Cálcio/genética , ATPases Transportadoras de Cálcio/metabolismo , Deleção de Genes , Modelos Biológicos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Fenótipo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
7.
Hum Genet ; 138(1): 61-72, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30535804

RESUMO

ATP2B2 encodes the PMCA2 Ca2+ pump that plays an important role in maintaining ion homeostasis in hair cells among others by extrusion of Ca2+ from the stereocilia to the endolymph. Several mouse models have been described for this gene; mice heterozygous for loss-of-function defects display a rapidly progressive high-frequency hearing impairment. Up to now ATP2B2 has only been reported as a modifier, or in a digenic mechanism with CDH23 for hearing impairment in humans. Whole exome sequencing in hearing impaired index cases of Dutch and Polish origins revealed five novel heterozygous (predicted to be) loss-of-function variants of ATP2B2. Two variants, c.1963G>T (p.Glu655*) and c.955delG (p.Ala319fs), occurred de novo. Three variants c.397+1G>A (p.?), c.1998C>A (p.Cys666*), and c.2329C>T (p.Arg777*), were identified in families with an autosomal dominant inheritance pattern of hearing impairment. After normal newborn hearing screening, a rapidly progressive high-frequency hearing impairment was diagnosed at the age of about 3-6 years. Subjects had no balance complaints and vestibular testing did not yield abnormalities. There was no evidence for retrocochlear pathology or structural inner ear abnormalities. Although a digenic inheritance pattern of hearing impairment has been reported for heterozygous missense variants of ATP2B2 and CDH23, our findings indicate a monogenic cause of hearing impairment in cases with loss-of-function variants of ATP2B2.


Assuntos
Biomarcadores/análise , Predisposição Genética para Doença , Perda Auditiva/genética , Mutação , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Seguimentos , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Prognóstico , Adulto Jovem
8.
Toxicol Lett ; 295: 162-172, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29935216

RESUMO

In pancreatic ß cells, which produce and secrete insulin, Ca2+ signals contribute to insulin production and secretion. Bisphenol A (BPA) and octylphenol (OP) are reported to increase plasma insulin levels and insulin transcription factors, but regulation of plasma glucose levels did not decrease proportionally to the insulin increase. We hypothesized that BPA and OP disrupt calcium homeostasis resulting in insulin resistance through induction of endoplasmic reticulum (ER) stress. BPA and OP treatment leads to survival of pancreatic ß cells against streptozotocin, but despite an increased insulin level, serum glucose regulation is not properly regulated. The expression of genes involved in transporting calcium ions to the cytosol and ER decreased while the expression of those affecting the removal of calcium from the cytosol and ER increased. Depletion of calcium from the ER leads to ER stress and can induce insulin resistance. Insulin resistance is also confirmed by insulin-responsive gene, such as glucose transporter 4 (GLUT4) and IRS2, expression. Taken together, these results imply that disruption of calcium homeostasis by BPA and OP induces ER stress and leads to insulin resistance, especially in a streptozotocin (STZ) -induced type 1 diabetes mellitus model.


Assuntos
Compostos Benzidrílicos/toxicidade , Cálcio/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 1/induzido quimicamente , Disruptores Endócrinos/toxicidade , Resistência à Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Fenóis/toxicidade , Animais , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Morte Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/patologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Homeostase , Insulina/sangue , Proteínas Substratos do Receptor de Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/efeitos dos fármacos , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Estreptozocina , Canais de Cátion TRPV/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo
9.
Eur J Endocrinol ; 178(3): R101-R111, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29348113

RESUMO

Aldosterone is the main mineralocorticoid hormone in humans and plays a key role in maintaining water and electrolyte homeostasis. Primary aldosteronism (PA), characterized by autonomous aldosterone overproduction by the adrenal glands, affects 6% of the general hypertensive population and can be either sporadic or familial. Aldosterone-producing adenoma (APA) and bilateral adrenal hyperplasia (BAH) are the two most frequent subtypes of sporadic PA and 4 forms of familial hyperaldosteronism (FH-I to FH-IV) have been identified. Over the last six years, the introduction of next-generation sequencing has significantly improved our understanding of the molecular mechanisms responsible for autonomous aldosterone overproduction in both sporadic and familial PA. Somatic mutations in four genes (KCNJ5, ATP1A1, ATP2B3 and CACNA1D), differently implicated in intracellular ion homeostasis, have been identified in nearly 60% of the sporadic APAs. Germline mutations in KCNJ5 and CACNA1H cause FH-III and FH-IV, respectively, while germline mutations in CACNA1D cause the rare PASNA syndrome, featuring primary aldosteronism seizures and neurological abnormalities. Further studies are warranted to identify the molecular mechanisms underlying BAH and FH-II, the most common forms of sporadic and familial PA whose molecular basis is yet to be uncovered.


Assuntos
Canais de Cálcio Tipo L/genética , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Hiperaldosteronismo/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , ATPase Trocadora de Sódio-Potássio/genética , Aldosterona/biossíntese , Variação Genética , Humanos
10.
Cell Microbiol ; 20(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29113016

RESUMO

Cryptococcus neoformans is a basidiomycetous yeast and the cause of cryptococcosis in immunocompromised individuals. The most severe form of the disease is meningoencephalitis, which is one of the leading causes of death in HIV/AIDS patients. In order to access the central nervous system, C. neoformans relies on the activity of certain virulence factors such as urease, which allows transmigration through the blood-brain barrier. In this study, we demonstrate that the calcium transporter Pmc1 enables C. neoformans to penetrate the central nervous system, because the pmc1 null mutant failed to infect and to survive within the brain parenchyma in a murine systemic infection model. To investigate potential alterations in transmigration pathways in these mutants, global expression profiling of the pmc1 mutant strain was undertaken, and genes associated with urease, the Ca2+ -calcineurin pathway, and capsule assembly were identified as being differentially expressed. Also, a decrease in urease activity was observed in the calcium transporter null mutants. Finally, we demonstrate that the transcription factor Crz1 regulates urease activity and that the Ca2+ -calcineurin signalling pathway positively controls the transcription of calcium transporter genes and factors related to transmigration.


Assuntos
Sistema Nervoso Central/microbiologia , Cryptococcus neoformans/metabolismo , Cryptococcus neoformans/patogenicidade , Proteínas Fúngicas/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Animais , Transporte Biológico/fisiologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/microbiologia , Encéfalo/metabolismo , Encéfalo/microbiologia , Calcineurina/metabolismo , Cálcio/metabolismo , Linhagem Celular , Criptococose/metabolismo , Criptococose/microbiologia , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Meningoencefalite/metabolismo , Meningoencefalite/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Vacúolos/metabolismo , Vacúolos/microbiologia , Virulência/fisiologia , Fatores de Virulência/metabolismo
11.
Arch Physiol Biochem ; 124(1): 45-53, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28758804

RESUMO

Erythrocyte membrane is a suitable model to study various metabolic and physiological functions as it undergoes variety of biochemical changes during aging. An age-dependent modulatory effect of rapamycin on erythrocyte membrane functions is completely unknown. Therefore, the present study was undertaken to investigate the effect of rapamycin on age-dependent impaired activities of transporters/exchangers, altered levels of redox biomarkers, viz. protein carbonyl (PC), lipid hydroperoxides (LHs), total thiol (-SH), sialic acid (SA) and intracellular calcium ion [Ca2+]i, and osmotic fragility of erythrocyte membrane. A significant reduction in membrane-bound activities of Na+/K+-ATPase (NKA) and Ca2+-ATPase (PMCA), and levels of -SH and SA was observed along with a simultaneous induction in Na+/H+ exchanger (NHE) activity and levels of [Ca2+]i, PC, LH and osmotic fragility in old-aged rats. Rapamycin was found to be a promising age-delaying drug that significantly reversed the aging-induced impaired activities of membrane-bound ATPases and altered levels of redox biomarkers.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Modelos Biológicos , Estresse Oxidativo/efeitos dos fármacos , Sirolimo/farmacologia , Envelhecimento/sangue , Envelhecimento/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Biomarcadores/sangue , Biomarcadores/metabolismo , Membrana Eritrocítica/enzimologia , Membrana Eritrocítica/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peróxidos Lipídicos/antagonistas & inibidores , Peróxidos Lipídicos/sangue , Peróxidos Lipídicos/metabolismo , Masculino , Ácido N-Acetilneuramínico/sangue , Ácido N-Acetilneuramínico/metabolismo , Fragilidade Osmótica/efeitos dos fármacos , ATPases Transportadoras de Cálcio da Membrana Plasmática/química , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar , Reprodutibilidade dos Testes , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo
12.
Cell Mol Life Sci ; 75(8): 1461-1482, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29085954

RESUMO

Three isoforms of plasma membrane Ca2+-ATPase (PMCA) are expressed in the kidney. While PMCA1 and PMCA4 play major role in regulating Ca2+ reabsorption, the role for PMCA2 remains vaguely defined. To define PMCA2 function, PMCA2-interacting complex was characterized by immunoprecipitation followed by nanoLC-ESI-Qq-TripleTOF MS/MS (IP-MS). After subtracting non-specific binders using isotype-controlled IP-MS, 474 proteins were identified as PMCA2-interacting partners. Among these, eight were known and 20 were potential PMCA2-interacting partners based on bioinformatic prediction, whereas other 446 were novel and had not been previously reported/predicted. Quantitative immuno-co-localization assay confirmed the association of PMCA2 with these partners. Gene ontology analysis revealed binding activity as the major molecular function of PMCA2-interacting complex. Functional validation using calcium oxalate monohydrate (COM) crystal-protein binding, crystal-cell adhesion, and crystal internalization assays together with neutralization by anti-PMCA2 antibody compared to isotype-controlled IgG and blank control, revealed a novel role of PMCA2 as a COM crystal-binding protein that was crucial for crystal retention and uptake. In summary, a large number of novel PMCA2-interacting proteins have been defined and a novel function of PMCA2 as a COM crystal-binding protein sheds light onto its involvement, at least in part, in kidney stone pathogenesis.


Assuntos
Oxalato de Cálcio/metabolismo , Cálculos Renais/metabolismo , Rim/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Animais , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/metabolismo , Oxalato de Cálcio/química , Cristalização , Cães , Expressão Gênica , Ontologia Genética , Imunoprecipitação , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Rim/química , Rim/patologia , Cálculos Renais/química , Cálculos Renais/patologia , Células Madin Darby de Rim Canino , Anotação de Sequência Molecular , ATPases Transportadoras de Cálcio da Membrana Plasmática/química , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Ligação Proteica , Mapeamento de Interação de Proteínas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Mycopathologia ; 183(2): 315-327, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29086141

RESUMO

The vacuolar-type H+-ATPase (V-ATPase) is essential for many cell processes. Our previous study has demonstrated that Tfp1 is a putative subunit of V-ATPase, loss of which causes disorders in calcium homeostasis and decreased resistance to oxidative stress. In this study, we found that further deletion of PMC1, a vacuolar calcium pump, in tfp1∆/∆ mutant led to more severe dysregulation of calcium homeostasis. Besides, the tfp1∆/∆pmc1∆/∆ mutant was more sensitive to H2O2 and had a higher ROS level. As is known, V-ATPase mutants are sensitive to NaCl, and PMC1 mutant is resistant against NaCl. However, the tfp1∆/∆pmc1∆/∆ mutant exhibited sensitivity to NaCl. Mechanism study demonstrated that their sensitivity was associated with reduced osmotic resistance caused by relatively low expression of GPD1. In addition, we first found that NaCl addition significantly declined ROS levels in tfp1∆/∆ and tfp1∆/∆pmc1∆/∆ mutants. In tfp1∆/∆ mutant, decreased ROS levels were relevant to enhanced antioxidant activities. However, in tfp1∆/∆pmc1∆/∆ mutant, reduced ROS resulted from decreased total calcium content, revealing that NaCl affected ROS levels in the two mutants through different mechanisms. Taken together, our data indicated that loss of both TFP1 and PMC1 further affected calcium homeostasis and other cellular processes in Candida albicans and provides a potential antifungal target.


Assuntos
Cálcio/metabolismo , Candida albicans/fisiologia , Homeostase , Pressão Osmótica , ATPases Transportadoras de Cálcio da Membrana Plasmática/deficiência , ATPases Translocadoras de Prótons/deficiência , Candida albicans/genética , Técnicas de Inativação de Genes , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Espécies Reativas de Oxigênio/análise , Cloreto de Sódio/metabolismo
14.
Proteomics ; 17(23-24)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29105980

RESUMO

Current treatments for advanced prostate cancer focus on inhibition of the androgen receptor (AR) by androgen deprivation therapy (ADT). However, complex interactions mediated by tumor suppressors, oncogenes, aberrations of AR expression, or de novo androgen production have been shown to induce the adaptive response of prostate cancer, leading to the development of castration resistant prostate cancer. In this study, we report the effects of AR antagonist, enzalutamide on the protein contents of extracellular vesicles (EVs). EVs mediate cell-to-cell communication and increasing evidence shows the role of EVs in promoting cancer survival and metastasis. We found that treatment with enzalutamide alters the secretion of EVs, one of which is a plasma membrane calcium pump, ATP2B1/PMCA ATPase, as an AR-regulated EV protein. We highlight the networks of interactions between AR, Ca2+ , and ATP2B1, where the extracellular proteins thrombospondin-1, gelsolin, and integrinß1 were previously reported as regulators for cancer progression and metastasis, indicating the potential role of EV-derived proteins in mediating calcium homoeostasis under AR inhibition by enzalutamide. Our data further highlight the cross-talk between AR signaling and EV pathways in mediating resistance toward ADT.


Assuntos
Adenocarcinoma/metabolismo , Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/química , Transdução de Sinais/efeitos dos fármacos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Vesículas Extracelulares/efeitos dos fármacos , Gelsolina/metabolismo , Humanos , Integrina beta1/metabolismo , Masculino , Feniltioidantoína/farmacologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Trombospondina 1/metabolismo , Células Tumorais Cultivadas
15.
J Biol Chem ; 292(51): 21047-21059, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29042438

RESUMO

Acute pancreatitis is a disease associated with inflammation and tissue damage. One protein that protects against acute injury, including ischemic injury to both the kidney and heart, is renalase, which is secreted into the blood by the kidney and other tissues. However, whether renalase reduces acute injury associated with pancreatitis is unknown. Here, we used both in vitro and in vivo murine models of acute pancreatitis to study renalase's effects on this condition. In isolated pancreatic lobules, pretreatment with recombinant human renalase (rRNLS) blocked zymogen activation caused by cerulein, carbachol, and a bile acid. Renalase also blocked cerulein-induced cell injury and histological changes. In the in vivo cerulein model of pancreatitis, genetic deletion of renalase resulted in more severe disease, and administering rRNLS to cerulein-exposed WT mice after pancreatitis onset was protective. Because pathological increases in acinar cell cytosolic calcium levels are central to the initiation of acute pancreatitis, we also investigated whether rRNLS could function through its binding protein, plasma membrane calcium ATPase 4b (PMCA4b), which excretes calcium from cells. We found that PMCA4b is expressed in both murine and human acinar cells and that a PMCA4b-selective inhibitor worsens pancreatitis-induced injury and blocks the protective effects of rRNLS. These findings suggest that renalase is a protective plasma protein that reduces acinar cell injury through a plasma membrane calcium ATPase. Because exogenous rRNLS reduces the severity of acute pancreatitis, it has potential as a therapeutic agent.


Assuntos
Monoaminoxidase/metabolismo , Pâncreas/metabolismo , Pancreatite/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Células Acinares/efeitos dos fármacos , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Inflamatórios não Esteroides/uso terapêutico , Biomarcadores/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Carbacol/farmacologia , Linhagem Celular , Ceruletídeo/toxicidade , Ativação Enzimática/efeitos dos fármacos , Técnica Indireta de Fluorescência para Anticorpo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Hipertensão/etiologia , Hipertensão/prevenção & controle , Ligantes , Moduladores de Transporte de Membrana/farmacologia , Camundongos , Camundongos Knockout , Monoaminoxidase/sangue , Monoaminoxidase/genética , Monoaminoxidase/uso terapêutico , Pâncreas/efeitos dos fármacos , Pâncreas/imunologia , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/patologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/antagonistas & inibidores , ATPases Transportadoras de Cálcio da Membrana Plasmática/química , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Ácido Taurolitocólico/análogos & derivados , Ácido Taurolitocólico/farmacologia
16.
Neuron ; 96(4): 827-838.e9, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29056295

RESUMO

Plasma membrane Ca2+-ATPases (PMCAs), a family of P-type ATPases, extrude Ca2+ ions from the cytosol to the extracellular space and are considered to be key regulators of Ca2+ signaling. Here we show by functional proteomics that native PMCAs are heteromeric complexes that are assembled from two pore-forming PMCA1-4 subunits and two of the single-span membrane proteins, either neuroplastin or basigin. Contribution of the two Ig domain-containing proteins varies among different types of cells and along postnatal development. Complex formation of neuroplastin or basigin with PMCAs1-4 occurs in the endoplasmic reticulum and is obligatory for stability of the PMCA proteins and for delivery of PMCA complexes to the surface membrane. Knockout and (over)-expression of both neuroplastin and basigin profoundly affect the time course of PMCA-mediated Ca2+ transport, as well as submembraneous Ca2+ concentrations under steady-state conditions. Together, these results establish neuroplastin and basigin as obligatory auxiliary subunits of native PMCAs and key regulators of intracellular Ca2+ concentration.


Assuntos
Basigina/metabolismo , Cálcio/metabolismo , Glicoproteínas de Membrana/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Animais , Retículo Endoplasmático/metabolismo , Feminino , Masculino , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Subunidades Proteicas/metabolismo
17.
J Physiol ; 595(24): 7383-7398, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29023784

RESUMO

KEY POINTS: The role of plasma membrane Ca2+ -ATPase 1 (PMCA1) in Ca2+ homeostasis and electrical stability in atrial tissue has been investigated at both organ and cellular levels in mice with cardiomyocyte-specific deletion of PMCA1 (PMCA1cko ) The PMCA1cko hearts became more susceptible to atrial arrhythmic stress conditions than PMCA1loxP/loxP hearts. PMCA1 deficiency alters cellular Ca2+ homeostasis under both baseline and stress conditions. PMCA1 is required for maintaining cellular Ca2+ homeostasis and electrical stability in murine atria under stress conditions. ABSTRACT: To determine the role of plasma membrane Ca2+ -ATPase 1 (PMCA1) in maintaining Ca2+ homeostasis and electrical stability in the atrium under physiological and stress conditions, mice with a cardiomyocyte-specific deletion of PMCA1 (PMCA1cko ) and their control littermates (PMCA1loxP/loxP ) were studied at the organ and cellular levels. At the organ level, the PMCA1cko hearts became more susceptible to atrial arrhythmias under rapid programmed electrical stimulation compared with the PMCA1loxP/loxP hearts, and such arrhythmic events became more severe under Ca2+ overload conditions. At the cellular level, the occurrence of irregular-type action potentials of PMCA1cko atrial myocytes increased significantly under Ca2+ overload conditions and/or at higher frequency of stimulation. The decay of Na+ /Ca2+ exchanger current that followed a stimulation protocol was significantly prolonged in PMCA1cko atrial myocytes under basal conditions, with Ca2+ overload leading to even greater prolongation. In conclusion, PMCA1 is required for maintaining Ca2+ homeostasis and electrical stability in the atrium. This is particularly critical during fast removal of Ca2+ from the cytosol, which is required under stress conditions.


Assuntos
Cálcio/metabolismo , Átrios do Coração/metabolismo , Potenciais da Membrana , Miócitos Cardíacos/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Animais , Função Atrial , Células Cultivadas , Átrios do Coração/citologia , Homeostase , Masculino , Camundongos , Miócitos Cardíacos/fisiologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo
18.
J Hum Hypertens ; 31(12): 787-794, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28934190

RESUMO

It is important to understand what genetic risk factors lead to hypertension and how genotype-specific dietary and lifestyle modification can mitigate the risk of developing hypertension. The ATP2B1 rs17249754 gene, which encodes a calcium pump expressed in vascular smooth muscle was identified as having variants that conferred higher or lower risk of hypertension-with the major allele carriers being increased at risk. However, the effects of dietary intakes on risk of hypertension among carriers of the different alleles have not been fully elucidated. Therefore, we evaluated ATP2B1 rs17249754 and its interaction with dietary intakes of sodium (Na), potassium (K) and calcium (Ca) on the risk of developing hypertension using the Ansan/Ansung (n=8842) and City-Rural (n=5512) cohorts from the Korean Genome and Epidemiology Study. Carriers of the major allele of ATP2B1 rs17249754 were at greater risk of developing hypertension and high Na intake and low Ca increased the risk more in major allele than among minor allele carriers. High potassium intake was more protective against hypertension in the subjects expressing minor alleles and a low Na/K intake ratio was the most consistently beneficial to the subjects expressing the minor allele. When controlling for Na and K, low Ca intake was associated with a substantially higher risk for high systolic blood pressure in the major allele carriers compared with minor allele, suggesting good calcium status is especially important for the major allele carriers. In conclusion, people with the major allele of ATP2B1 rs17249754 are susceptible to hypertension especially in low intake of Ca and high ratio of Na and K.


Assuntos
Cálcio na Dieta , Hipertensão/etiologia , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Potássio na Dieta , Sódio na Dieta/efeitos adversos , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Aging Cell ; 16(5): 1104-1113, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28795531

RESUMO

Hypertension is a well-established risk factor for adverse cardiovascular events, and older age is a risk factor for the development of hypertension. Genomewide association studies have linked ATP2B1, the gene for the plasma membrane calcium ATPase 1 (PMCA1), to blood pressure (BP) and hypertension. Here, we present the effects of reduction in the expression of PMCA1 on BP and small artery structure and function when combined with advancing age. Heterozygous PMCA1 null mice (PMCA1Ht ) were generated and conscious BP was measured at 6 to 18 months of age. Passive and active properties of isolated small mesenteric arteries were examined by pressure myography. PMCA1Ht mice exhibited normal BP at 6 and 9 months of age but developed significantly elevated BP when compared to age-matched wild-type controls at ≥12 months of age. Decreased lumen diameter, increased wall thickness and increased wall:lumen ratio were observed in small mesenteric arteries from animals 9 months of age and older, indicative of eutrophic remodelling. Increases in mesenteric artery intrinsic tone and global intracellular calcium were evident in animals at both 6 and 18 months of age. Thus, decreased expression of PMCA1 is associated with increased BP when combined with advancing age. Changes in arterial structure precede the elevation of BP. Pathways involving PMCA1 may be a novel target for BP regulation in the elderly.


Assuntos
Envelhecimento/genética , Hipertensão/genética , Artérias Mesentéricas/metabolismo , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Remodelação Vascular/genética , Resistência Vascular/genética , Envelhecimento/metabolismo , Animais , Pressão Sanguínea/fisiologia , Cálcio/metabolismo , Expressão Gênica , Heterozigoto , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Masculino , Artérias Mesentéricas/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miografia , ATPases Transportadoras de Cálcio da Membrana Plasmática/deficiência
20.
J Clin Invest ; 127(8): 3065-3074, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28714864

RESUMO

The lack of mechanistic explanations for many genotype-phenotype associations identified by GWAS precludes thorough assessment of their impact on human health. Here, we conducted an expression quantitative trait locus (eQTL) mapping analysis in erythroblasts and found erythroid-specific eQTLs for ATP2B4, the main calcium ATPase of red blood cells (rbc). The same SNPs were previously associated with mean corpuscular hemoglobin concentration (MCHC) and susceptibility to severe malaria infection. We showed that Atp2b4-/- mice demonstrate increased MCHC, confirming ATP2B4 as the causal gene at this GWAS locus. Using CRISPR-Cas9, we fine mapped the genetic signal to an erythroid-specific enhancer of ATP2B4. Erythroid cells with a deletion of the ATP2B4 enhancer had abnormally high intracellular calcium levels. These results illustrate the power of combined transcriptomic, epigenomic, and genome-editing approaches in characterizing noncoding regulatory elements in phenotype-relevant cells. Our study supports ATP2B4 as a potential target for modulating rbc hydration in erythroid disorders and malaria infection.


Assuntos
ATPases Transportadoras de Cálcio/genética , Eritrócitos/citologia , Predisposição Genética para Doença , Malária/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Animais , Sistemas CRISPR-Cas , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Mapeamento Cromossômico , Elementos Facilitadores Genéticos , Epigenômica , Eritroblastos/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Células HEK293 , Humanos , Malária/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Fenótipo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA