Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Más filtros

Métodos Terapéuticos y Terapias MTCI
Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Int Med Res ; 51(11): 3000605231215202, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38017366

RESUMEN

We report a 15-year-old Chinese girl who presented with intermittent seizure episodes and had been misdiagnosed as having idiopathic epilepsy 5 years previously. Laboratory testing revealed hypocalcemia, hyperphosphatemia, and a high parathyroid hormone (PTH) concentration. She was subsequently shown to have pseudohypoparathyroidism type Ib (PHPIb) based on the results of methylation analysis of the GNAS gene, which showed a loss of methylation of the differentially methylated regions (DMR) of GNAS-AS1, GNAS-XL, and GNAS-A/B; and a gain of methylation of the DMR of the GNAS-NESP55 region. We adjusted the patient's medication by prescribing calcium and calcitriol supplements, and gradually reduced the doses of antiepileptic drugs, until they had been completely discontinued. As a result, the patient did not experience any further seizures or epileptiform symptoms; and had normal plasma calcium, phosphorus, and 25-hydroxyvitamin D concentrations and 24-hour urinary calcium excretion. In addition, her PTH concentration gradually normalized over 12 months, and no urinary stones were found on ultrasonographic examination. In conclusion, the clinical presentation of PHP is complex, and the condition is often misdiagnosed. The diagnosis and follow-up of the present patient have provide valuable insights that should contribute to informed clinical decision-making and the implementation of appropriate treatment strategies.


Asunto(s)
Epilepsia , Seudohipoparatiroidismo , Humanos , Femenino , Adolescente , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Metilación de ADN , Calcio , Estudios de Seguimiento , Cromograninas/genética , Seudohipoparatiroidismo/diagnóstico , Seudohipoparatiroidismo/genética , Hormona Paratiroidea , Epilepsia/genética , Errores Diagnósticos
2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(10): 1461-1466, 2022 Oct 28.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-36411698

RESUMEN

Pseudohypoparayhyroidism (PHP) is a rare autosomal dominant or recessive genetic disorder characterized by low calcium, high phosphorus, and target organ resistance to parathyroid. The clinical characteristics and genetic features in 4 patients with Type Ib PHP in the Third Xiangya Hospital, Central South University, have been reviewed. All 4 patients had low calcium, high phosphorus, and parathyroid resistance. Among them, 2 patients had slightly elevated thyroid stimulating hormone and mild features of Albright's hereditary osteodystrophy, and one patient had hypokalemia. No guanine nucleotide-binding protein alpha-stimulating activity polypeptide 1 (GNAS) and gene variant associated with hypokalemia were identified using the whole exome sequencing. The results of the methylation-specific multiple ligation-dependent probe amplification showed that there were abnormal methylation of the upstream differentially methylated regions of GNAS in the 4 patients. There were phenotype overlap among the various subtypes of PHP. Detection of GNAS gene methylation in patients with clinical suspicion of Type Ib PHP is helpful for the diagnosis and treatment of PHP.


Asunto(s)
Hipopotasemia , Seudohipoparatiroidismo , Humanos , Cromograninas/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Calcio , Seudohipoparatiroidismo/genética , Fósforo
3.
BMC Endocr Disord ; 22(1): 98, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35410271

RESUMEN

BACKGROUND: Pseudohypoparathyroidism (PHP) encompasses a highly heterogenous group of disorders, characterized by parathyroid hormone (PTH) resistance caused by mutations in the GNAS gene or other upstream targets. Here, we investigate the characteristics of a female patient diagnosed with PHP complicated with hypokalemia, and her family members. CASE PRESENTATION AND GENE ANALYSIS: A 27-year-old female patient occasionally exhibited asymptomatic hypocalcemia and hypokalemia during her pregnancy 1 year ago. Seven months after delivery, she experienced tetany and dysphonia with diarrhea. Tetany symptoms were relieved after intravenous calcium gluconate supplementation and she was then transferred to our Hospital. Laboratory assessments of the patient revealed hypokalemia, hypocalcemia and hyperphosphatemia despite elevated PTH levels. CT scanning of the brain revealed globus pallidus calcification. Possible mutations in GNAS and hypokalemia related genes were identified using WES, exon copies of STX16 were analized by MLPA and the methylation status of GNAS in three differential methylated regions (DMRs) was analyzed by methylation-specific polymerase chain reaction, followed by confirmation with gene sequencing. The patient was clinically diagnosed with PHP-1b. Loss of methylation in the A/B region and hypermethylation in the NESP55 region were detected. No other mutations in GNAS or hypokalemia related genes and no deletions of STX16 exons were detected. A negative family history and abnormal DMRs in GNAS led to a diagnosis of sporadic PHP-1b of the patient. CONCLUSIONS: Hypokalemia is a rare disorder associated with PHP-1b. Analysis of genetic and epigenetic mutations can aid in the diagnosis and accurate subtyping of PHP.


Asunto(s)
Hipocalcemia , Hipopotasemia , Seudohipoparatiroidismo , Tetania , Adulto , Cromograninas/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Humanos , Hipocalcemia/genética , Hipopotasemia/genética , Seudohipoparatiroidismo/complicaciones , Seudohipoparatiroidismo/diagnóstico , Seudohipoparatiroidismo/genética
4.
BMC Endocr Disord ; 21(1): 12, 2021 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-33422028

RESUMEN

BACKGROUND: Pseudohypoparathyroidism is a rare genetic disease characterized by hypocalcaemia and hyperphosphataemia due to the defect to the guanine nucleotide-binding protein alpha subunit (GNAS) gene. Patients with pseudoparathyroidism type 1a and 1c could manifest Albright's hereditary osteodystrophy and multiple hormone resistance including gonadotropin and thyroid stimulating hormone. CASE PRESENTATION: Here we report a Chinese man who presented with fatigue, recurrent seizure and Albright's hereditary osteodystrophy. His genetic study revealed a heterozygote mutation in the GNAS gene [NM_000516.4(GNAS): c2787_2788del (p.Val930AspfsTer12)]. After calcium and calcitriol supplement, his seizures achieved partially remission. CONCLUSIONS: We report a case of PHP1a or 1c with a novel frameshift mutation in GNAS gene in a patient presenting with AHO, as well as TSH and partial gonadotropin resistance. This mutation in this case has not been reported in literature and adds to the spectrum of genetic mutations related to PHP.


Asunto(s)
Cromograninas/genética , Mutación del Sistema de Lectura/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Seudohipoparatiroidismo/genética , Convulsiones/genética , Adulto , Pueblo Asiatico , Calcitriol/uso terapéutico , Calcio/uso terapéutico , Suplementos Dietéticos , Displasia Fibrosa Poliostótica/complicaciones , Hormonas/sangre , Humanos , Masculino , Mutación , Seudohipoparatiroidismo/complicaciones , Seudohipoparatiroidismo/diagnóstico por imagen , Recurrencia , Convulsiones/etiología , Tirotropina/sangre
5.
Dig Dis Sci ; 65(8): 2294-2301, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31925676

RESUMEN

BACKGROUND: Pancreatic cyst fluids (PCFs) enriched in tumor-derived DNA are a potential source of new biomarkers. The study aimed to analyze germinal variants and mutational profiles of cell-free (cf)DNA shed into the cavity of pancreatic cysts. METHODS: The study cohort consisted of 71 patients who underwent endoscopic ultrasound fine-needle aspiration of PCF. Five malignant cysts, 19 intraductal papillary mucinous neoplasms (IPMNs), 11 mucinous cystic neoplasms (MCNs), eight serous cystic neoplasms (SCNs), and 28 pseudocysts were identified. The sequencing of 409 genes included in Comprehensive Cancer Panel was performed using Ion Proton System. The mutation rate of the KRAS and GNAS canonical loci was additionally determined using digital PCR. RESULTS: The number of mutations detected with NGS varied from 0 to 22 per gene, and genes with the most mutations were: TP53, KRAS, PIK3CA, GNAS, ADGRA2, and APC. The frequencies of the majority of mutations did not differ between non-malignant cystic neoplasms and pseudocysts. NGS detected KRAS mutations in malignant cysts (60%), IPMNs (32%), MCNs (64%), SCNs (13%), and pseudocysts (14%), with GNAS mutations in 20%, 26%, 27%, 13%, and 21% of samples, respectively. Digital PCR-based testing increased KRAS (68%) and GNAS (52%) mutations detection level in IPMNs, but not other cyst types. CONCLUSIONS: We demonstrate relatively high rates of somatic mutations of cancer-related genes, including KRAS and GNAS, in cfDNA isolated from PCFs irrespectively of the pancreatic cyst type. Further studies on molecular mechanisms of pancreatic cysts malignant transformation in relation to their mutational profiles are required.


Asunto(s)
Ácidos Nucleicos Libres de Células/análisis , Quiste Pancreático/química , Neoplasias Pancreáticas/diagnóstico , Adulto , Anciano , Cromograninas/genética , Análisis Mutacional de ADN , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Humanos , Masculino , Persona de Mediana Edad , Quiste Pancreático/genética , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/genética , Estudios Prospectivos , Proteínas Proto-Oncogénicas p21(ras)/genética , Adulto Joven
6.
J Clin Endocrinol Metab ; 104(3): 823-826, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30418563

RESUMEN

Context: Type 1A pseudohypoparathyroidism (PHP-1A) is characterized by target organ resistance to PTH. Patients can present with various dysmorphic features; however, renal failure has not been classically described. Case Description: A female patient came to our attention at the age of 7 years with characteristic signs of PTH resistance (i.e., hypocalcemia, hyperphosphatemia, and high serum PTH levels). She also presented with hypothyroidism, early-onset obesity, short metacarpal bones, and multiple subcutaneous ossifications, leading to a clinical diagnosis of pseudohypoparathyroidism. In addition to her genetic condition, she had bilateral renal hypodysplasia that was slowly progressing to end-stage kidney disease. She received a kidney transplant at the age of 16 years and, after transplantation, experienced rapidly normalized calcium, phosphate, and PTH levels, allowing f withdrawal of vitamin D supplementation. Conclusions: To the best of our knowledge, ours is the first report of a patient with PHP-1A undergoing kidney transplantation. Normalization of biochemical parameters after the procedure demonstrated that renal tubular resistance to PTH is sufficient to explain the calcium/phosphate abnormalities observed in PHP-1A.


Asunto(s)
Túbulos Renales/fisiopatología , Hormona Paratiroidea/sangre , Seudohipoparatiroidismo/sangre , Insuficiencia Renal/fisiopatología , Calcio/sangre , Niño , Cromograninas/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Humanos , Trasplante de Riñón , Fosfatos/sangre , Seudohipoparatiroidismo/complicaciones , Seudohipoparatiroidismo/genética , Insuficiencia Renal/sangre , Insuficiencia Renal/etiología , Insuficiencia Renal/cirugía , Vitamina D/sangre
7.
Endocrinol Diabetes Nutr ; 64(10): 524-530, 2017 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29179855

RESUMEN

BACKGROUND: The receptor of parathyroid hormone and parathyroid hormone-related-protein (PTH/PTHrp) is located in the cell membrane of target tissues - kidney and osteoblasts. It is a G protein-coupled-receptor whose Gsα subunit is encoded by the GNAS gene. Our aim was to study whether the single nucleotide polymorphism (SNP) T393C of the GNAS gene is associated with renal stones, bone mineral density (BMD), or bone remodelling markers in primary hyperparathyroidism (PHPT). METHODS: An analysis was made of clinical and biochemical parameters and densitometric values in three areas and their relationship with the T393C SNP of the GNAS gene in 261 patients with primary hyperparathyroidism and in 328 healthy controls. Genotyping was performed using the Custom Taqman® SNP Genotyping assay. RESULTS: The genotype frequencies of GNAS T/C 393 were similar in the control and PHPT groups. No association was found between genotypes and clinical expression of PHPT (renal stones and bone fractures). A nonstatistically significant trend was seen to lower BMD in the lumbar spine, femoral neck, and total hip in both PHPT and control C homozygote subjects. CONCLUSION: Genetic susceptibility to PHPT related to the GNAS T393C polymorphism or a major influence in its development and clinical expression were found. A C allele-related susceptibility to lower BMD in trabecular bone in both PHPT and control subjects is not sufficient to suggest a more severe clinical expression of PHPT. This trend may be considered as a basis for further studies with larger sample sizes and complementary functional evaluation.


Asunto(s)
Cromograninas/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Hiperparatiroidismo Primario/genética , Polimorfismo de Nucleótido Simple , Anciano , Fosfatasa Alcalina/sangre , Biomarcadores , Densidad Ósea/genética , Remodelación Ósea/genética , Calcio/sangre , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Hiperparatiroidismo Primario/sangre , Hiperparatiroidismo Primario/complicaciones , Cálculos Renales/etiología , Masculino , Persona de Mediana Edad , España , Vitamina D/análogos & derivados , Vitamina D/sangre
8.
J Tradit Chin Med ; 37(2): 252-60, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-29961273

RESUMEN

OBJECTIVE: To observe the regulation of electroacupuncture on gene expression at calcium signaling pathways in mice with cerebral ischemia reperfusion. METHODS: Sixty male, inbred Kunming mice were randomly assigned to three groups: repeated cerebral ischemia reperfusion group (RG, n = 24), sham-operated group (SG, n = 12), and electroacupuncture group (EG, n = 24). Mice in RG and EG groups were modeled by repeated cerebral ischemia reperfusion surgery, and EG mice were treated with electroacupuncture for 30 min after recovery from anesthesia. Changes in gene expression profile of mice hippocampi were analyzed by global expression profile microarray. Genes that were up-regulated or down-regulated greater than 1.5 folds were considered to be biologically meaningful. Real-time quantitative polymerase chain reaction (q-PCR) method was used to verify the expression of selected genes based on the algorithm [2^ (ΔΔCt)]. RESULTS: Compared with SG mice, 242 genes showed different in expressions in RG mice: 107 down-regulated and 135 up-regulated. Compared with RG mice, 609 genes showed a difference of expression in EG mice: 315 down-regulated and 375 up-regulated. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated two pathways: calcium signaling and long-term potentiation in which 11 differentially expressed genes selected. Six of the 11 genes in the calcium signaling pathway were verified after real-time q-PCR testing. CONCLUSION: Electroacupuncture treatment of cerebral ischemia reperfusion appears to regulate Atp2a2, Cacna1e, Camk2a, Gnas, Grm1, Rapgef3 genes in the calcium signaling pathway.


Asunto(s)
Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Señalización del Calcio , Electroacupuntura , Hipocampo/metabolismo , Puntos de Acupuntura , Animales , Isquemia Encefálica/metabolismo , Canales de Calcio Tipo R/genética , Canales de Calcio Tipo R/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Cromograninas/genética , Cromograninas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Humanos , Masculino , Ratones , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Transcriptoma
9.
Ann Oncol ; 27(11): 2097-2103, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27502722

RESUMEN

BACKGROUND: Outcome of pseudomyxoma peritonei (PMP) after cytoreductive surgery (CRS) and hypertermic intraperitoneal chemotherapy (HIPEC) is heterogeneous even after adjusting for clinico-pathological prognostic variables. The identification of additional prognostic or even predictive biomarkers is an unmet clinical need. PATIENTS AND METHODS: Forty patients with mucinous appendiceal tumors and PMP were clinically eligible and had evaluable tumor samples obtained after CRS and HIPEC. We carried out next-generations sequencing (NGS) of 50 gene's hotspot regions contained in the Hotspot Cancer Panel v2 using the Ion Torrent Personal Genome Machine platform (Life Technologies). RESULTS: KRAS and GNAS mutations were found in 72% and 52%, and their allelic frequency was below 10% in 55% and 43% of samples, respectively. KRAS and GNAS mutations were associated with worse progression-free survival (PFS) at univariate analysis (P = 0.006 and 0.011, respectively). At multivariate analysis, only KRAS mutations were independently associated with PFS (P = 0.012); GNAS mutations were not-being significantly associated with other poor prognostic features such as incomplete cytoreduction or KRAS mutations. Validation of results was carried out in an independent bi-institutional cohort of 25 patients and the prognostic effect of KRAS mutations was again confirmed in the multivariate model (P = 0.029). NGS approach allowed the discovery of other potentially druggable mutations such as those in PI3K, AKT, LKB1, FGFR3 and PDGFRA. CONCLUSIONS: Given the homogeneity of this series and the sensitivity of NGS in this low-cellularity tumor, we demonstrated for the first time a poor prognostic role of KRAS mutations.


Asunto(s)
Biomarcadores de Tumor/genética , Cromograninas/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Seudomixoma Peritoneal/genética , Adulto , Anciano , Cisplatino/administración & dosificación , Terapia Combinada , Procedimientos Quirúrgicos de Citorreducción , Supervivencia sin Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hipertermia Inducida , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Seudomixoma Peritoneal/tratamiento farmacológico , Seudomixoma Peritoneal/patología , Seudomixoma Peritoneal/cirugía
10.
Pediatr Nephrol ; 31(5): 795-800, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26628282

RESUMEN

BACKGROUND: In patients with pseudohypoparathyroidism type 1b (PHP1b) due to a tissue-specific imprinting defect in the G-protein α-subunit, skeletal disorders can arise from the bones being sensitive to parathyroid hormone (PTH) while the kidneys remain resistant to this hormone. CASE-DIAGNOSIS/TREATMENT: We report a 4.8-year-old girl with PHP1b who presented with an abnormal gait, severe skeletal changes and elevated levels of serum PTH (2844 pg/ml), phosphate (7.2 mg/dl) and bone turnover markers. Traditional treatment with calcium and calcitriol failed to suppress PTH secretion, which was still elevated at 2877 pg/ml after 14 months of therapy, nor did it correct the other clinical, biochemical and radiographic abnormalities. The addition of cinacalcet to the treatment regimen over the subsequent 32 months resulted in normalization of serum PTH (58 ng/ml), phosphate (4.9 mg/dl) and bone turnover markers, and resolution of the radiographic changes, with no adverse effects noted. CONCLUSIONS: Due to its ease of administration, we recommend the addition of cinacalcet into the armamentarium of medications available to treat children with PHP1b.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Calcimiméticos/uso terapéutico , Cinacalcet/uso terapéutico , Seudohipoparatiroidismo/tratamiento farmacológico , Biomarcadores/sangre , Calcitriol/uso terapéutico , Calcio/sangre , Calcio/uso terapéutico , Preescolar , Cromograninas/genética , Metilación de ADN , Suplementos Dietéticos , Exones , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Predisposición Genética a la Enfermedad , Humanos , Hormona Paratiroidea/sangre , Fenotipo , Fosfatos/sangre , Seudohipoparatiroidismo/sangre , Seudohipoparatiroidismo/diagnóstico , Seudohipoparatiroidismo/genética , Factores de Tiempo , Resultado del Tratamiento , Regulación hacia Arriba , Seudohipoparatiroidismo
11.
J Clin Endocrinol Metab ; 92(3): 1145-54, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17200173

RESUMEN

CONTEXT: Genetic factors are important for the development of obesity. However, the genetic background of obesity still remains unclear. OBJECTIVE: Our objective was to search for obesity-related genes using a large number of gene-based single-nucleotide polymorphisms (SNPs). DESIGN AND SETTING: We conducted case-control association analyses using 94 obese patients and 658 controls with 62,663 SNPs selected from the SNP database. SNPs that possessed P < or = 0.02 were further analyzed using 796 obese and 711 control subjects. One SNP (rs3764220) in the secretogranin III (SCG3) gene showed the lowest P value (P = 0.0000019). We sequenced an approximately 300-kb genomic region around rs3764220 and discovered SNPs for haplotype analyses. SCG3 was the only gene within a haplotype block that contained rs3764220. The functions of SCG3 were studied. PATIENTS: Obese subjects (body mass index > or = 30 kg/m(2), n = 890) and control subjects (general population; n = 658, body mass index < or = 25 kg/m(2); n = 711) were recruited for this study. RESULTS: Twelve SNPs in the SCG3 gene including rs3764220 were in almost complete linkage disequilibrium and significantly associated with an obesity phenotype. Two SNPs (rs16964465, rs16964476) affected the transcriptional activity of SCG3, and subjects with the minor allele seemed to be resistant to obesity (odds ratio, 9.23; 95% confidence interval, 2.77-30.80; chi(2) = 19.2; P = 0.0000067). SCG3 mRNA and immunoreactivity were detected in the paraventricular nucleus, lateral hypothalamic area, and arcuate nucleus, and the protein coexisted with orexin, melanin-concentrating hormone, neuropeptide Y, and proopiomelanocortin. SCG3 formed a granule-like structure together with these neuropeptides. CONCLUSIONS: Genetic variations in the SCG3 gene may influence the risk of obesity through possible regulation of hypothalamic neuropeptide secretion.


Asunto(s)
Cromograninas/genética , Cromograninas/metabolismo , Neuropéptidos/metabolismo , Obesidad/genética , Polimorfismo de Nucleótido Simple , Vesículas Secretoras/metabolismo , Adulto , Anciano , Regulación del Apetito/fisiología , Estudios de Casos y Controles , Femenino , Humanos , Hipotálamo/metabolismo , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Neuropéptidos/fisiología
12.
Neuroscience ; 88(2): 405-24, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10197763

RESUMEN

Nerve growth factor differentiates precursor cells into sympathetic neurons. Does acquisition of a "neuronal" phenotype after nerve growth factor involve biosynthesis of chromogranin A, the major soluble protein in chromaffin granule cores? Nerve growth factor activated chromogranin A gene expression 7.6-fold in PC12 pheochromocytoma cells, and similarly activated PC12-transfected mouse, rat or human chromogranin A promoter/reporter constructs. Chromogranin A promoter 5'-deletions narrowed the nerve growth factor response element to a region from - 77 to - 61 bp upstream of the cap site, a region containing the chromogranin A cyclic AMP response element (TGACGTAA). Three different site-directed mutations of the cyclic AMP response element each reduced the nerve growth factor effect by >90%. Transfer of the cyclic AMP response element to a heterologous (thymidine kinase) promoter activated that promoter approximately 5-fold after nerve growth factor, while transfer of a cyclic AMP response element point-gap mutant (TGA-GTAA) to a heterologous promoter abolished the nerve growth factor effect. These findings indicate that the cyclic AMP response element in cis is, at least in part, both necessary and sufficient to activate the chromogranin A gene. Chemical blockade of the nerve growth factor receptor TrkA or the mitogen-activated protein kinase pathway component MEK substantially diminished nerve growth factor-induced expression of chromogranin A. By contrast, the response of chromogranin A to nerve growth factor was not impaired after blockade of phospholipase C-gamma or phosphoinositide-3 kinase. Chemical blockade of TrkA, Ras, MEK or mitogen-activated protein kinase similarly inhibited nerve growth factor activation of chromogranin A. Expression of constitutively activated Ras, Raf or MEK mutants increased chromogranin A promoter activity. Expression of dominant negative (inhibitory) mutants of Sos, Ha-Ras, Rafl, mitogen-activated protein kinase, ribosomal protein S6 serine kinase II (CREB kinase) or CREB (KCREB) each inhibited the nerve growth factor-induced increase in chromogranin A promoter activity. Thus, each component of the mitogen-activated protein kinase pathway is crucially involved in relaying the nerve growth factor signal in trans to the chromogranin A gene, in the following proposed sequence: nerve growth factor --> TrkA --> Shc/Grb2/Sos --> Ras --> Raf --> MEK --> mitogen-activated protein kinase --> ribosomal protein S6 serine kinase II --> CREB cyclic AMP response element.


Asunto(s)
Carbazoles , Catecolaminas/metabolismo , Gránulos Cromafines/química , Cromograninas/genética , Indoles , Factores de Crecimiento Nervioso/farmacología , Alcaloides/farmacología , Animales , Secuencia de Bases , Proteínas Quinasas Dependientes de Calcio-Calmodulina/antagonistas & inhibidores , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Manzanilla , Células Cromafines/química , Células Cromafines/efectos de los fármacos , Células Cromafines/enzimología , Gránulos Cromafines/efectos de los fármacos , Gránulos Cromafines/metabolismo , Cromogranina A , Cromograninas/biosíntesis , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Eliminación de Gen , Expresión Génica/efectos de los fármacos , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Lovastatina/farmacología , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos , Datos de Secuencia Molecular , Mutagénesis/fisiología , Aceites Volátiles/farmacología , Células PC12 , Isomerasa de Peptidilprolil/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Plantas Medicinales , Regiones Promotoras Genéticas/fisiología , Inhibidores de Proteínas Quinasas , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , ARN Mensajero/metabolismo , Ratas , Proteínas Tirosina Quinasas Receptoras/genética , Receptor trkA , Receptores de Factor de Crecimiento Nervioso/genética , Transcripción Genética/fisiología , Transfección , Fosfolipasas de Tipo C/antagonistas & inhibidores , Fosfolipasas de Tipo C/metabolismo
13.
J Biol Chem ; 263(23): 11559-63, 1988 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-3403545

RESUMEN

Chromogranin A (CGA), also referred to as secretory protein I, is an acidic protein that has been detected in all neuroendocrine cell types examined and is often present in large amounts relative to other secreted proteins. For example, CGA comprises at least 40% of the soluble protein of the adrenal chromaffin granule, and it appears to be the major secretory protein in the parathyroid secretory granules. CGA complementary DNAs (cDNAs) from bovine adrenal and pituitary have recently been cloned and sequenced and found to be nearly identical. A region of bovine CGA has a high degree of amino acid sequence identity to pancreastatin, a recently isolated porcine peptide that inhibits glucose-induced insulin secretion. This suggests that CGA may be a prohormone. We have cloned and sequenced a human cDNA encoding CGA. This human CGA cDNA has an overall 86% nucleic acid identity to the bovine cDNA. Like the bovine CGA cDNA, the human cDNA has little homology to pancreastatin at the 5' region of this peptide but significant amino acid homology to the carboxyl-terminal portion of pancreastatin where the biologic activity resides. There is an area within the pancreastatin region of human CGA and porcine pancreastatin with a 70% amino acid identity to the calcium-binding moiety of the E-F hand proteins such as parvalbumin and oncomodulin. These data suggest that CGA and pancreastatin may both be members of a larger family of calcium-binding proteins.


Asunto(s)
Cromograninas/genética , Clonación Molecular , ADN/análisis , Proteínas del Tejido Nervioso/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Calcio/metabolismo , Bovinos , Cromogranina A , Humanos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Hormonas Pancreáticas/análisis , Porcinos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA