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1.
J Pediatr Endocrinol Metab ; 18(2): 133-42, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15751602

RESUMEN

11beta-Hydroxylase deficiency is a common form of congenital adrenal hyperplasia causing virilization of the female fetus and hypertension. DNA analysis of the gene (CYP11B1) encoding 11beta-hydroxylase has been reported previously to be effective in the prenatal diagnosis of one affected female fetus. In that case, prenatal treatment with dexamethasone resulted in normal female genitalia. We now report five new pregnancies that underwent prenatal diagnosis for 11beta-hydroxylase deficiency. In the first family, the proband is homozygous for a T318M mutation and all fetuses from four subsequent pregnancies are carriers. In a second family, the mother is homozygous for a A331V mutation and was started on dexamethasone, but identification of a homozygous normal fetus led to the discontinuation of treatment. In another family, the fetus was a male homozygous for R384Q and treatment was discontinued. Lastly, a novel G444D mutation in exon 8 was identified and proven to reduce 11beta-hydroxylase activity.


Asunto(s)
Hiperplasia Suprarrenal Congénita/diagnóstico , Hiperplasia Suprarrenal Congénita/genética , Cromosomas Humanos Par 8/genética , Enfermedades Fetales/diagnóstico , Enfermedades Fetales/genética , Esteroide 11-beta-Hidroxilasa/genética , Adolescente , Hiperplasia Suprarrenal Congénita/terapia , Amniocentesis , Niño , Muestra de la Vellosidad Coriónica , Consanguinidad , Análisis Mutacional de ADN , Dexametasona/uso terapéutico , Femenino , Enfermedades Fetales/tratamiento farmacológico , Tamización de Portadores Genéticos/métodos , Glucocorticoides/uso terapéutico , Humanos , Lactante , Recién Nacido , Masculino , Mutación , Linaje , Embarazo , Diagnóstico Prenatal , Virilismo/genética , Virilismo/prevención & control
2.
Biochem Pharmacol ; 55(11): 1807-18, 1998 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-9714299

RESUMEN

The HIV-1 protein Rev, critical for translation of incompletely spliced retroviral mRNAs encoding capsid elements, requires a host cell protein termed "eukaryotic initiation factor 5A" (eIF-5A). This is the only protein containing hypusine, a lysine-derived hydroxylated residue that determines its proposed bioactivity, the translation of a subset of cellular mRNAs controlling G1-to-S transit of the cell cycle. We postulated that inhibiting the hypusine-forming deoxyhypusyl hydroxylase (DOHH) should, by depleting eukaryotic initiation factor 5A, compromise Rev function and thus reduce HIV-1 multiplication. We now report that the alpha-hydroxypyridones, specifically mimosine, a natural product, and deferiprone, an experimental drug, inhibited deoxyhypusyl hydroxylase in T-lymphocytic and promonocytic cell lines and, in a concentration-dependent manner, suppressed replication of HIV-1. However, the alpha-hydroxypyridones did not affect the formation of unspliced or multiply spliced HIV-1 transcripts. Rather, these agents caused Rev-dependent incompletely spliced HIV-1 mRNA such as gag, but not cellular "housekeeping" mRNAs, to disappear from polysomes. Consequently, alpha-hydroxypyridone-mediated depletion of eIF-5A decreased biosynthesis of structural HIV-1 protein encoded by gag, measured as p24, whereas the induced formation of cellular protein like tumor necrosis factor alpha remained unaffected. By interfering with the translation of incompletely spliced retroviral mRNAs, these compounds restrict HIV-1 to the early, nongenerative phase of its reproductive cycle. In the inducibly HIV-1 expressing T-cell line ACH-2, the deoxyhypusyl hydroxylase inhibitors triggered extensive apoptosis, particularly of cells that actively produce HIV-1. Selective suppression of retroviral protein biosynthesis and preferential apoptosis of retrovirally infected cells by alpha-hydroxypyridones point to a novel mode of antiretroviral action.


Asunto(s)
Fármacos Anti-VIH/farmacología , Inhibidores Enzimáticos/farmacología , VIH-1/efectos de los fármacos , Lisina/análogos & derivados , Oxigenasas de Función Mixta/antagonistas & inhibidores , Proteínas de Unión al ARN , Replicación Viral/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Transformada , Deferiprona , Proteína p24 del Núcleo del VIH/metabolismo , VIH-1/enzimología , VIH-1/genética , VIH-1/fisiología , Humanos , Lisina/antagonistas & inhibidores , Microscopía Electrónica , Mimosina/farmacología , Factores de Iniciación de Péptidos/antagonistas & inhibidores , Piridonas/farmacología , ARN Mensajero/antagonistas & inhibidores , ARN Viral/antagonistas & inhibidores , Linfocitos T/efectos de los fármacos , Linfocitos T/virología , Factor 5A Eucariótico de Iniciación de Traducción
3.
FEBS Lett ; 366(2-3): 92-8, 1995 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-7789538

RESUMEN

S phase entry, i.e. start of DNA replication, is a crucial step in proliferation. Inhibition of S phase entry correlates with inhibition of hypusine formation, an event affecting only the eukaryotic initiation factor 5A (eIF-5A). Its hypusine-containing sequence was postulated to authorize polysomal utilization of specific transcripts for proteins necessary to enable DNA replication. Using mimosine to reversibly suppress the hypusine-forming deoxyhypusyl hydroxylase (E.C. 1.14.99.29) in cells while differentially displaying their polysomal versus non-polysomal mRNA populations, we report the detection and classification of several mRNA species that indeed disappear from and reappear at polysomes in concert with inhibition and disinhibition, respectively, of hypusine formation. Based on initial sequence data, two translationally controlled enzymes, both critical for proliferation, are identified as candicate products of such mRNAs, methionine adenosyltransferase (E.C. 2.5.1.6) and cytochrome-c oxidase (EC 1.9.3.1) subunit I. The existence of such putative hypusine-dependent messenger nucleic acids (hymns) provides the basis for a proposal on their molecular function in onset of multiplication.


Asunto(s)
Replicación del ADN , Complejo IV de Transporte de Electrones/metabolismo , Fase G1 , Lisina/análogos & derivados , Metionina Adenosiltransferasa/metabolismo , Factores de Iniciación de Péptidos/fisiología , Polirribosomas/química , ARN Mensajero/genética , Proteínas de Unión al ARN , Fase S , Secuencia de Bases , Línea Celular , Complejo IV de Transporte de Electrones/genética , Humanos , Linfocitos , Lisina/biosíntesis , Metionina Adenosiltransferasa/genética , Mimosina/farmacología , Oxigenasas de Función Mixta/antagonistas & inhibidores , Datos de Secuencia Molecular , ARN Mensajero/aislamiento & purificación , Alineación de Secuencia , Factor 5A Eucariótico de Iniciación de Traducción
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