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1.
J Endocrinol Invest ; 47(7): 1633-1640, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38457058

RESUMEN

PURPOSE: In light of the growing concern over the possible link between SARS-CoV2 infection and autoimmune diseases, we conducted a review to investigate the impact of the pandemic outbreak on thyroid diseases. METHODS: We carried out a narrative review of all pediatric cases described in the literature, mainly focusing on the possible association of COVID-19 with the incidence of autoimmune and post-infective thyroid diseases (namely Hashimoto's Thyroiditis (HT), Grave's Disease (GD) and Sub-Acute Thyroiditis (SAT)). We also felt it was necessary to provide a brief review of Non-thyroidal Illness Syndrome (NTIS) and Multisystem Inflammatory Syndrome in Children (MIS-C) because of their overlap with thyroiditis. RESULTS: There is currently no conclusive evidence linking SARS-CoV-2 infection with an increased incidence of autoimmune thyroiditis (AT) in pediatric age. However, SAT may be a mild complication of SARS-CoV-2 infection, as is the case with other viral infections. SAT typically resolves on its own and does not require treatment. NTIS may be associated with inflammatory complications, such as MIS-C, and admission to intensive care. It may also be considered a prognostic risk factor for severe disease. The hypothesized pathogenetic mechanisms of thyroid damage in COVID-19 include direct damage due to the significant expression of angiotensin-converting enzyme 2 (ACE2) in the thyroid gland, which is a ligand for the virus, and indirect damage due to immune dysregulation, such as the overproduction of IL-6, which is thought to be part of the pathogenesis of thyroiditis. CONCLUSION: However, due to the limited evidence available, further prospective longitudinal studies are required to clarify the relationship between COVID-19 and thyroid disease in children and adolescents, as well as to investigate any potential long-term consequences.


Asunto(s)
COVID-19 , Humanos , COVID-19/complicaciones , COVID-19/epidemiología , Niño , SARS-CoV-2 , Enfermedad de Hashimoto/epidemiología , Adolescente , Síndrome de Respuesta Inflamatoria Sistémica/epidemiología , Tiroiditis/epidemiología , Incidencia , Enfermedad de Graves/epidemiología , Enfermedad de Graves/complicaciones
2.
J Endocrinol Invest ; 47(4): 777-793, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37891382

RESUMEN

PURPOSE: Tall stature is defined as height greater than the threshold of more than 2 standard deviations above the average population height for age, sex, and ethnicity. Many studies have described the main aspects of this condition during puberty, but an analysis of the characteristics that the physician should consider in the differential diagnosis of gigantism-tall stature secondary to a pituitary tumour-during the transition age (15-25 years) is still lacking. METHODS: A comprehensive search of English-language original articles was conducted in the MEDLINE database (December 2021-March 2022). We selected all studies regarding epidemiology, genetic aspects, and the diagnosis of tall stature and gigantism during the transition age. RESULTS: Generally, referrals for tall stature are not as frequent as expected because most cases are familial and are usually unreported by parents and patients to endocrinologists. For this reason, lacking such experience of tall stature, familiarity with many rarer overgrowth syndromes is essential. In the transition age, it is important but challenging to distinguish adolescents with high constitutional stature from those with gigantism. Pituitary gigantism is a rare disease in the transition age, but its systemic complications are very relevant for future health. Endocrine evaluation is crucial for identifying conditions that require hormonal treatment so that they can be treated early to improve the quality of life and prevent comorbidities of individual patient in this age range. CONCLUSION: The aim of our review is to provide a practical clinical approach to recognise adolescents, potentially affected by gigantism, as early as possible.


Asunto(s)
Gigantismo , Adolescente , Humanos , Adulto Joven , Adulto , Calidad de Vida , Síndrome , Diagnóstico Diferencial , Estatura
3.
J Exp Zool A Ecol Integr Physiol ; 331(1): 52-60, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30246445

RESUMEN

Mytilus galloprovincialis female specimens were collected from two mussel farms located in two sites next to Castel dell'Ovo, a historical complex located in the Naples Bay. Such sites were named, respectively, A-area and B-area for the different microbiological parameters so that mussels from A-area can be sold without purification, whereas mussels from B-area must be purified before sale. The mussels were collected during the nonreproductive (summer 2009) and reproductive periods (autumn 2009). Gonadosomatic index, structural organization of the ovary, presence of apoptosis, estrogen receptors expression, as well as the bisphenol A (BPA) content in the ovaries, were evaluated. Ovaries from specimens collected in area B showed a different and significant distribution of the investigated biomarkers as well as of BPA content in respect to those measured in the A-area specimens, confirming that mussels are valid sentinel organisms to biomonitor in the Naples bay too.


Asunto(s)
Distribución Animal , Bahías , Mytilus/anatomía & histología , Ovario/anatomía & histología , Ovario/fisiología , Animales , Apoptosis/fisiología , Compuestos de Bencidrilo/química , Femenino , Italia , Fenoles/química , Reacción en Cadena en Tiempo Real de la Polimerasa , Contaminantes Químicos del Agua/química
4.
Transl Med UniSa ; 11: 55-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25674551

RESUMEN

Abacavir is a nucleoside reverse transcriptase inhibitor largely used as part of the antiretroviral therapy in Human Immunodeficiency Virus (HIV)-infected patients. Some individuals (2-9%) who start an abacavir treatment show an immunologic reaction indicated as hypersensitivity reaction syndrome (HSR) that is often responsible for therapy discontinuation and could represent a life-threatening event. Some studies demonstrated a correlation between this adverse reaction and the class I of the major histocompatibility complex (MHC) allele, HLA-B*57.01, in several populations, including Caucasians. Nowadays, International HIV treatment guidelines recommend the HLA-B*57.01 genotyping before abacavir administration to reduce the incidence of HSR. Both male and female HIV-infected patients were enrolled at the Infectious Diseases Division at the University Hospital of Salerno, and admitted to a prospective HLAB*57.01 screening. Genetic analysis was carried out through two sequential Real-Time PCR reactions in which Sybr-Green was used. Out of 248 patients, 215 were Italians from Southern Italy and 33 were coming from several non-EU members countries. All were genotyped: 6 Italians (2.8%) and 1 of the non-EU group (3%) were identified as HLAB*57.01 carriers. In this paper we present our experience in the field of abacavir pharmacogenetic and confirm the importance of Real Time PCR as a valid and cost-effective HLA-B*57.01 typing methodology.

5.
Gene ; 406(1-2): 124-33, 2007 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-17825504

RESUMEN

In P. lividus sea urchin the H3.3 histone variant is coded by an mRNA characterized by a long 3'UTR containing ARE (AU-Rich element) motifs. RNA stability assays performed in rabbit reticulocyte lysate showed that such 3'UTR affects the degradation rate of the transcripts. In fact, chimeric molecules containing the 3'UTR of H3.3 transcript, ligated to the coding region of the rabbit beta-globin transcript, were unstable whereas chimeric molecules containing mainly the coding region of the H3.3 transcript were stable as the wild-type globin mRNA. Three proteins (45kDa, 32kDa and 25kDa) that bind specifically the 3'UTR have been revealed in the whole protein extracts of embryos at different stages of development. PLAUF, a P. lividus RNA-binding protein similar to human and rodent AUF1 proteins, was identified as the 32kDa factor using anti-PLAUF antibody in Western blot and supershift mobility assays. Moreover the recombinant GST-PLAUF protein specifically binds part of the H3.3 3'UTR and in vitro affects the half-life of the transcript. In addition in situ hybridization experiments demonstrated that PLAUF and H3.3 histone mRNAs co-localize in embryos at different stages of development. In conclusion all the reported results suggest that PLAUF can bind in vivo the 3'UTR of the H3.3 histone mRNA and plays some role in the stability of the mRNA.


Asunto(s)
Regiones no Traducidas 3'/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo D/metabolismo , Histonas/metabolismo , Estabilidad del ARN , Erizos de Mar/genética , Animales , ARN Mensajero , Proteínas de Unión al ARN/metabolismo , Erizos de Mar/embriología
6.
J Pharmacol Exp Ther ; 320(1): 365-75, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17005916

RESUMEN

Histamine H3 receptor inverse agonists are known to enhance the activity of histaminergic neurons in brain and thereby promote vigilance and cognition. 1-{3-[3-(4-Chlorophenyl)propoxy]propyl}piperidine, hydrochloride (BF2.649) is a novel, potent, and selective nonimidazole inverse agonist at the recombinant human H3 receptor. On the stimulation of guanosine 5'-O-(3-[35S]thio)triphosphate binding to this receptor, BF2.649 behaved as a competitive antagonist with a Ki value of 0.16 nM and as an inverse agonist with an EC50 value of 1.5 nM and an intrinsic activity approximately 50% higher than that of ciproxifan. Its in vitro potency was approximately 6 times lower at the rodent receptor. In mice, the oral bioavailability coefficient, i.e., the ratio of plasma areas under the curve after oral and i.v. administrations, respectively, was 84%. BF2.649 dose dependently enhanced tele-methylhistamine levels in mouse brain, an index of histaminergic neuron activity, with an ED50 value of 1.6 mg/kg p.o., a response that persisted after repeated administrations for 17 days. In rats, the drug enhanced dopamine and acetylcholine levels in microdialysates of the prefrontal cortex. In cats, it markedly enhanced wakefulness at the expense of sleep states and also enhanced fast cortical rhythms of the electroencephalogram, known to be associated with improved vigilance. On the two-trial object recognition test in mice, a promnesiant effect was shown regarding either scopolamine-induced or natural forgetting. These preclinical data suggest that BF2.649 is a valuable drug candidate to be developed in wakefulness or memory deficits and other cognitive disorders.


Asunto(s)
Agonistas de los Receptores Histamínicos/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Piperidinas/farmacología , Receptores Histamínicos H3/efectos de los fármacos , Acetilcolina/metabolismo , Animales , Gatos , Dopamina/metabolismo , Electroencefalografía/efectos de los fármacos , Cobayas , Liberación de Histamina/efectos de los fármacos , Humanos , Imidazoles/metabolismo , Masculino , Metilhistaminas/farmacología , Ratones , Ratones Endogámicos C57BL , Piperidinas/farmacocinética , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Receptores Histamínicos H3/fisiología , Escopolamina/farmacología
7.
Minerva Chir ; 61(1): 31-7, 2006 Feb.
Artículo en Italiano | MEDLINE | ID: mdl-16568020

RESUMEN

AIM: Biliodigestive anastomoses are widely used in the treatment of biliary obstruction. METHODS: A survey is presented of the personal case series treated during the last 5 years. Thirty biliodigestive anastomose have been performed both for neoplastic disease and for benign lesions. RESULTS: The biliodigestive anastomosis has been performed with the Blumgart's technique both for benign and malignant tumors. CONCLUSIONS: The authors point out that experience is of the utmost importance for the operation success. Major attention is paid to the surgical technique used for the biliodigestive anastomosis and a retrospective analysis is made.


Asunto(s)
Colestasis/cirugía , Conducto Colédoco/cirugía , Duodeno/cirugía , Yeyuno/cirugía , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/métodos , Colestasis/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
8.
Zygote ; 14(4): 349-57, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17266793

RESUMEN

Testicular cell-to-cell interactions play a key role in the regulation of spermatogenesis. In the testis, cell contacts are mediated through several mechanisms, including paracrine and direct contacts depending on gap junctional pathways. Gap junctions require connexin (Cx) channels and connexin-43 (Cx43) represent the most abundant Cx found in mammalian testis. Little is known about Cx expression in non-mammalian testis. Here we report the partial cloning of a Cx43 transcript of 381 bp from Rana esculenta testis. We also demonstrate that, in the frog testis, Cx43 transcript and protein show a parallel temporal and spatial pattern of expression throughout the reproductive annual cycle, with higher levels from September to January (when spermatogenesis is at a maximum level). In situ hybridization, carried out on testis collected in October, indicated that Leydig cells (LC) and Sertoli cells express Cx43 transcript, while the hybridization signal was less intense in germ cells. To obtain more information on Cx43 expression in the frog testis, we have used ethane-dimethane sulphonate (EDS), a toxin that specifically destroys LC. RT-PCR analysis shows a progressive decrease in Cx43 expression in EDS-treated testis from day 1 to day 4 after the injection, associated with LC destruction. Moreover, Cx43 expression returns to normal on day 28, when a new population of LC reappear in the interstitium, indicating that Cx43 is mainly expressed by LC. Taken together our data provide evidence that Cx43 is present in the frog testis with an important role in spermatogenesis.


Asunto(s)
Conexina 43/genética , Conexina 43/metabolismo , Rana esculenta/metabolismo , Testículo/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/genética , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Rana esculenta/crecimiento & desarrollo , Estaciones del Año , Homología de Secuencia de Aminoácido , Espermatogénesis/genética , Espermatogénesis/fisiología
9.
Gene ; 347(1): 99-107, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-15715964

RESUMEN

Preliminary results have shown that various proteins bind long 3'UTR of the transcript for Paracentrotus lividus sea urchin H3.3 histone variant and are probably implicated in mRNA instability. In order to identify these RNA-binding proteins, we screened a lambda-ZAPII cDNA expression library prepared from poly(A) mRNA extracted from sea urchin embryos at blastula stage. We isolated a cDNA that codes for a novel RNA-binding protein homologous to rat and human AUF1 family proteins and we refer to it as PLAUF. Proteins present in the whole lysate of the phages expressing PLAUF bound specifically in vitro the 3'UTR of the H3.3 histone transcript. Northern blot analysis revealed three PLAUF transcripts that are already present in unfertilized eggs; during development their amount increased starting from 4-blastomere embryos and reached the plateau at blastula stage. While the transcription start point was unique, longer 3'UTRs were revealed by 3'RACE approach and further cDNA library screening. Moreover RT-PCR showed the presence of at least one alternative spliced mRNA that codes for a protein with different COOH terminus. The structure of the PLAUF gene was determined by screening a P. lividus sea urchin genomic library with the PLAUF cDNA as probe. Analysis of the positive clones showed that the PLAUF gene is split in 10 exons and 9 introns spanning a distance of about 10 kb. Moreover we demonstrated that the exon 9 was alternative spliced during mRNA processing.


Asunto(s)
Regiones no Traducidas 3'/genética , Histonas/genética , Paracentrotus/genética , Estabilidad del ARN/genética , Proteínas de Unión al ARN/genética , Regiones no Traducidas 3'/metabolismo , Empalme Alternativo/genética , Empalme Alternativo/fisiología , Secuencia de Aminoácidos , Animales , Blastómeros/fisiología , Blástula/fisiología , ADN Complementario/genética , Biblioteca Genómica , Histonas/metabolismo , Humanos , Ratones , Datos de Secuencia Molecular , Óvulo/fisiología , Paracentrotus/fisiología , Estabilidad del ARN/fisiología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/metabolismo , Homología de Secuencia de Aminoácido
10.
J Mol Evol ; 59(4): 458-63, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15638457

RESUMEN

The H3L histone variant gene in Paracentrotus lividus (sea urchin) shows almost all typical features of the replication-dependent histone genes, but it codes for the H3.3 histone protein with the S.//. A.IG amino acid motif, which is typical of the variants synthesized in a replication-independent manner. "H3L-like" histone genes have been found in several unrelated organisms. These genes are intronless and encode for the typical H3.3 histone proteins. The newly described family of H3L-like variants, nearly ubiquitous within the animal kingdom, could represent the common ancestor of H3 and H3.3 histone genes.


Asunto(s)
Histonas/genética , Familia de Multigenes , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Variación Genética , Genoma , Humanos , Ratones , Datos de Secuencia Molecular , Técnicas de Amplificación de Ácido Nucleico , Alineación de Secuencia , Análisis de Secuencia , Transcripción Genética
11.
Gene ; 272(1-2): 199-208, 2001 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-11470526

RESUMEN

The turnover and localization of the enzyme DNA (cytosine-5) methyltransferase (Dnmt1) were studied during Paracentrotus lividus sea urchin embryo development using antibody preparations against the NH(2) and COOH-terminal regions of the molecule. The antibodies reveal, by Western blots and whole-mount analyses, that the enzyme is differently required during embryonic development. The changeover point is at blastula stage, where a proteolytic mechanism hydrolyses the enzyme present in all embryonic cells by removing a peptide of about 45 kDa from the amino terminal region of the 190 kDa enzyme initially synthesized on maternal transcripts. The resulting 145 kDa enzyme shows modified catalytic properties, different antibody reactivity and is rapidly destroyed in the few hours before gastrulation. At more advanced stages of development the enzyme is newly synthesized but only in particular cell types, among which neurons. The data show that Dnmt1 is removed from embryonic cells before gastrulation to be synthesized again at different levels in different cell types, indicating that the concentration of Dnmt1 is critical for the various differentiated cells of the developing sea urchin embryo.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/metabolismo , Embrión no Mamífero/enzimología , Erizos de Mar/enzimología , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Western Blotting , ADN/genética , ADN/metabolismo , ADN (Citosina-5-)-Metiltransferasas/química , ADN (Citosina-5-)-Metiltransferasas/inmunología , Desarrollo Embrionario , Isoenzimas/química , Isoenzimas/metabolismo , Peso Molecular , Pruebas de Precipitina , Especificidad por Sustrato
12.
Biochim Biophys Acta ; 1519(1-2): 39-45, 2001 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-11406269

RESUMEN

We have isolated the Paracentrotus lividus sea urchin H3.3 histone gene and characterized the nucleotide sequences of the gene and its proximal promoter. Band shift experiments showed that two cAMP/PMA responsive elements (CRE/TRE), present in the proximal promoter, bind nuclear factors present in embryos at the blastula and gastrula stages (CRE1) and at the blastula stage (CRE2). The putative H3.3 coding region activating sequences (CRAS) failed to bind nuclear factors while the corresponding elements of the two replication-dependent genes (H3L and late H3) clearly recognized nuclear proteins. These results suggest some role of the CRE/TRE elements but not CRAS elements in the transcriptional regulation of the replication-independent histone genes in invertebrates.


Asunto(s)
Histonas/genética , Erizos de Mar/genética , Animales , Bacteriófagos/genética , Secuencia de Bases , Codón , Replicación del ADN , ADN Complementario/genética , Regulación del Desarrollo de la Expresión Génica , Biblioteca Genómica , Histonas/química , Datos de Secuencia Molecular , Proteínas Nucleares/genética , Regiones Promotoras Genéticas , Erizos de Mar/embriología , Transcripción Genética
13.
Endocrinology ; 142(7): 3231-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11416046

RESUMEN

A complementary DNA (cDNA) encoding a frog relaxin/insulin member family (fRLX) from testis cDNA library was isolated and characterized. The fRLX cDNA predicted a 155-amino acid protein with a low homology to mammalian RLF and relaxin. Northern blot analysis revealed a single transcript expressed in the interstitial compartment, RT-PCR, evidenced that fRLX is expressed at low levels in the oviduct and ovary too. The predicted mature fRLX protein, composed of the signal peptide, B, C, and A domains, has conserved amino acid sequences in the characteristic functional domains. A different expression of the transcript was found during the frog reproductive cycle, with a peak in Spring. After administration of ethane dimethane sulfonate, by in situ hybridization, fRLX messenger RNA disappeared from the interstitial compartment and reappeared again at the time of generating of a new population of Leydig cells (LC), strongly indicating that LC are the interstitial cell type expressing fRLX. Preliminary results obtained by in situ hybridization, performed on testis of hypophysectomized frogs evidenced a pituitary control of fRLX expression. This study is the first cloning of a relaxin/insulin family member in a nonmammalian vertebrate. In addition, because fRLX expression changes during the annual cycle suggesting its involvement in spermatogenesis, fRLX may be considered a new marker for the study of spermatogenesis in the Rana esculenta.


Asunto(s)
Proteínas/genética , Proteínas/aislamiento & purificación , Rana esculenta/genética , Rana esculenta/metabolismo , Testículo/metabolismo , Secuencia de Aminoácidos/genética , Animales , Clonación Molecular , ADN Complementario/genética , Insulina , Masculino , Datos de Secuencia Molecular , Hipófisis/fisiología , Proteínas/metabolismo , ARN Mensajero/metabolismo , Espermatogénesis/fisiología , Testículo/citología , Factores de Tiempo , Distribución Tisular
14.
Mech Dev ; 102(1-2): 271-4, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11287209

RESUMEN

We describe the cloning and the expression pattern of insulin promoter factor 1 in the ascidian Ciona intestinalis (Ci-IPF1). Northern blot analysis showed that transcripts appeared at the late tailbud stage and increased at the larval stage. We have raised a specific antibody against the Ci-IPF1-GST fusion protein to determine the spatial expression of this gene. The protein is immunodetected at the larval stage in the sensory vesicle, in the visceral ganglion and in the mesenchymal cells. Our results support the hypothesis that IPF1/IDX1 might have extrapancreatic functions during animal development, particularly in neural cells.


Asunto(s)
Ciona intestinalis/metabolismo , Larva/metabolismo , Transactivadores/biosíntesis , Secuencia de Aminoácidos , Animales , Northern Blotting , Clonación Molecular , ADN Complementario/metabolismo , Glutatión Transferasa/metabolismo , Proteínas de Homeodominio/metabolismo , Inmunohistoquímica , Mesodermo/metabolismo , Modelos Genéticos , Datos de Secuencia Molecular , Neuronas/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Homología de Secuencia de Aminoácido , Factores de Tiempo , Transactivadores/genética
15.
Mech Dev ; 99(1-2): 173-6, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11091088

RESUMEN

Several homeobox-containing genes related to Drosophila Distal-less (Dll) have been isolated from a wide variety of organisms and have been shown to function as developmental regulators. While in Drosophila only one Dll gene has been described so far, in Vertebrates many components of the Dlx multigenic family have been characterized. This suggests that, during the evolution of the Chordate phylum, the Dlx genes arose from an ancestral Dll/Dlx gene via gene duplication. We have previously reported the isolation of two Dll-related homeoboxes from the protochordate Ciona intestinalis, and described their clustered arrangement (Gene 156 (1995) 253). Here we present the detailed genomic organization and spatial-temporal expression of these two genes, Ci-Dll-A and Ci-Dll-B, and describe the isolation and characterization of another member of the ascidian family of Dll-related genes, which we tentatively named Ci-Dll-C.


Asunto(s)
Cordados no Vertebrados , Ciona intestinalis/embriología , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/genética , Factores de Transcripción , Animales , Northern Blotting , ADN Complementario/metabolismo , Biblioteca de Genes , Hibridación in Situ , Modelos Genéticos , Familia de Multigenes , Factores de Tiempo , Distribución Tisular
16.
Differentiation ; 66(1): 23-30, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10997589

RESUMEN

A cDNA encoding an RNA binding protein has been isolated from a cDNA library prepared from larvae of the ascidian Ciona intestinalis. The putative protein of 162 amino acids contained in the N-terminal region one copy of the consensus sequence RNA binding domain and in the C-terminal region a glycine-rich domain. The in vitro translated protein bound various RNA homopolymers, preferentially polyU, polyA, and polyG, and the binding was affected by increasing ionic strength. Northern blot analysis revealed a single transcript of about 0.7 kb in length that was present during embryonic development with two major peaks of accumulation at gastrula and larval stages. Whole-mount in situ hybridization experiments on embryos at different stages of development showed gene expression mainly in mesenchymal cells and in neural tissue.


Asunto(s)
Ciona intestinalis/embriología , Ciona intestinalis/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas de Unión al ARN/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Perfilación de la Expresión Génica , Hibridación in Situ , Datos de Secuencia Molecular , Oligorribonucleótidos/genética , Oligorribonucleótidos/metabolismo , Especificidad de Órganos , Unión Proteica , Estructura Terciaria de Proteína , ARN sin Sentido/genética , ARN sin Sentido/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
17.
FEBS Lett ; 460(2): 380-4, 1999 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-10544268

RESUMEN

The enzyme S-adenosylmethionine-DNA (cytosine-5)-methyltransferase has been identified, first time for invertebrates, in embryos of the marine polychaete annelid worm Chaetopterus variopedatus. The molecule has been isolated from embryos at 15 h of development. It is a single peptide of about 200 kDa molecular weight, cross-reacting with antibodies against sea urchin DNA methyltransferase. The enzymatic properties of the molecule are similar to those of Dnmt1 methyltransferases isolated from other organisms, but with the peculiarity to be unable to make 'de novo' methylation on double stranded DNA.


Asunto(s)
Anélidos/enzimología , ADN (Citosina-5-)-Metiltransferasas/química , Metilación de ADN , Animales , Western Blotting , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Expresión Génica , Cinética , Micrococcus luteus/genética , Factores de Tiempo
18.
Development ; 126(22): 5149-59, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10529431

RESUMEN

In solitary ascidians the fate of endoderm is determined at a very early stage of development and depends on cytoplasmic factors whose nature has not been determined. We have isolated a member of the NK-2 gene family, Cititf1, from the ascidian Ciona intestinalis, showing high sequence homology to mammalian TITF1. The Cititf1 gene was expressed in all endodermal precursors at the pregastrula and gastrula stages, and is thus the first specific regulatory endodermal marker to be isolated from an ascidian. Cititf1 expression was downregulated at the end of gastrulation to reappear at middle tailbud and larval stages in the most anterior and ventral parts of head endoderm, regions which give rise, after metamorphosis, to the adult endostyle, where Cititf1 mRNA was still present. Microinjection of Cititf1 mRNA into fertilized eggs resulted in tadpole larvae with abnormalities in head-trunk development consequent to the formation of excess endoderm, perhaps due to recruitment of notochord precursors to an endodermal fate. These data suggest that Cititf1 plays an important role in normal endoderm differentiation during ascidian embryogenesis.


Asunto(s)
Endodermo/fisiología , Proteínas de Homeodominio/genética , Factores de Transcripción/genética , Animales , Ciona intestinalis/embriología , Proteínas de Drosophila , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/aislamiento & purificación , Humanos , Mamíferos , Proteínas Nucleares/química , Proteínas Nucleares/fisiología , Homología de Secuencia de Aminoácido , Factor Nuclear Tiroideo 1 , Factores de Transcripción/biosíntesis , Factores de Transcripción/química , Factores de Transcripción/fisiología
19.
Mech Dev ; 88(1): 123-6, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10525197

RESUMEN

We report the cloning and expression pattern of Ci-msxb the second Ciona intestinalis homeobox gene homologue to the Drosophila muscle segment homeobox (msh) gene. Northern blot analysis showed that transcripts appeared at gastrula stage, peaked in the early tailbud and decreased during the tailed stages. Whole mount in situ hybridization showed that the Ci-msxb expression first is detected at 110 cell-stage in the blastomeres that are precursors of different tissue (muscle, spinal cord, endodermal strand, brain, mesenchyme, pigmented cells and primordial pharynx). Transcript level declined in mesoderm cells after the completion of gastrulation, but mRNAs were still present in the folding neural plate during neurulation and in the pigmented cells. Later, at larval stage, transcripts were present around the otolith and ocellus, in a restricted part of the nervous system and in the primordial pharynx; the gene expression was conserved after metamorphosis in the juvenile.


Asunto(s)
Ciona intestinalis/crecimiento & desarrollo , Ciona intestinalis/genética , Proteínas de Drosophila , Animales , Blastómeros , Ciona intestinalis/embriología , Drosophila/genética , Ectodermo , Embrión no Mamífero , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Larva , Datos de Secuencia Molecular , Sistema Nervioso/embriología , Sistema Nervioso/crecimiento & desarrollo , Homología de Secuencia de Aminoácido
20.
Development ; 126(21): 4737-48, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10518491

RESUMEN

Hox genes play a fundamental role in the establishment of chordate body plan, especially in the anteroposterior patterning of the nervous system. Particularly interesting are the anterior groups of Hox genes (Hox1-Hox4) since their expression is coupled to the control of regional identity in the anterior regions of the nervous system, where the highest structural diversity is observed. Ascidians, among chordates, are considered a good model to investigate evolution of Hox gene, organisation, regulation and function. We report here the cloning and the expression pattern of CiHox3, a Ciona intestinalis anterior Hox gene homologous to the paralogy group 3 genes. In situ hybridization at the larva stage revealed that CiHox3 expression was restricted to the visceral ganglion of the central nervous system. The presence of a sharp posterior boundary and the absence of transcript in mesodermal tissues are distinctive features of CiHox3 expression when compared to the paralogy group 3 in other chordates. We have investigated the regulatory elements underlying CiHox3 neural-specific expression and, using transgenic analysis, we were able to isolate an 80 bp enhancer responsible of CiHox3 activation in the central nervous system (CNS). A comparative study between mouse and Ciona Hox3 promoters demonstrated that divergent mechanisms are involved in the regulation of these genes in vertebrates and ascidians.


Asunto(s)
Tipificación del Cuerpo/fisiología , Sistema Nervioso Central/embriología , Ciona intestinalis/embriología , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Secuencia Conservada , Electroporación , Embrión no Mamífero , Elementos de Facilitación Genéticos , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Fenómenos Fisiológicos del Sistema Nervioso , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , beta-Galactosidasa/genética
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