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1.
Science ; 241(4866): 705-8, 1988 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-3041593

RESUMEN

The human pS2 gene is specifically expressed under estrogen transcriptional control in a subclass of estrogen receptor-containing human breast cancer cells. The pS2 gene encodes an 84-amino acid protein that is secreted after signal peptide cleavage. The distribution of pS2 protein in normal human tissues was studied with antibodies to pS2; pS2 was specifically expressed and secreted by mucosa cells of the normal stomach antrum and body of both female and male individuals. Moreover, no estrogen receptor could be detected in these cells, indicating that pS2 gene expression is estrogen-independent in the stomach. The function of the pS2 protein in the gastrointestinal tract is unknown. However, the pS2 protein is similar in sequence to a porcine pancreatic protein that has been shown to inhibit gastrointestinal motility and gastric secretion.


Asunto(s)
Neoplasias de la Mama/metabolismo , Mucosa Gástrica/metabolismo , Regulación de la Expresión Génica , Proteínas de Neoplasias/biosíntesis , Proteínas , Secuencia de Aminoácidos , Anticuerpos Monoclonales , Estrógenos/farmacología , Exones , Femenino , Histocitoquímica , Humanos , Técnicas para Inmunoenzimas , Masculino , Datos de Secuencia Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , ARN Mensajero/metabolismo , Receptores de Estrógenos/metabolismo , Homología de Secuencia de Ácido Nucleico , Distribución Tisular , Factor Trefoil-1 , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor
2.
Anim Genet ; 39(6): 662-5, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18717666

RESUMEN

To examine further a previously reported association between amylase gene polymorphism and growth in the Pacific oyster Crassostrea gigas, ecophysiological parameters and biochemical and molecular expression levels of alpha-amylase were studied in Pacific oysters of different amylase genotypes. Genotypes that previously displayed significantly different growth were found to be significantly different for ingestion and absorption efficiency. These estimated parameters, used in a dynamic energy budget model, showed that observed ingestion rates (unlike absorption efficiencies) allowed an accurate prediction of growth potential in these genotypes. The observed association between growth and amylase gene polymorphism is therefore more likely to be related to ingestion than to absorption efficiency. Additionally, relative mRNA levels of the two amylase cDNAs were also strongly associated with amylase gene polymorphism, possibly reflecting variation in an undefined regulatory region, although no corresponding variation was observed in specific amylase activity. Amylase gene sequences were determined for each genotype, showing the existence of only synonymous or functionally equivalent non-synonymous polymorphisms. The observed associations among growth, food consumption-related traits and amylase gene polymorphism are therefore more likely to be related to variation in the level of amylase gene expression than to functional enzymatic variants.


Asunto(s)
Amilasas/genética , Conducta Alimentaria , Ostreidae/genética , Polimorfismo Genético , Amilasas/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Cinética , Ostreidae/enzimología , Ostreidae/fisiología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
3.
Head Neck ; 40(4): 846-854, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29155470

RESUMEN

BACKGROUND: Indications for treatment and outcomes after endovascular management of carotid blowout syndrome for patients with head and neck cancer are not well defined. We investigated the safety and effectiveness of endovascular embolization and stent-graft reconstruction. METHODS: A literature review was performed for studies published between 2001 and 2015 with relevance to treatment outcomes. Our institutional database was examined to identify patients treated with endovascular techniques. RESULTS: A total of 266 patients were included. Rates of procedural stroke were higher after embolization of internal carotid artery (ICA)/common carotid artery (CCA) compared to stent graft (embolization 10.3%; stent graft 2.5%; P < .02). Stent graft of ICA/CCA was associated with higher rates of recurrent bleeding (embolization 9.1%; stent graft 31.9%; P < .01). CONCLUSION: Both embolization and stent grafts are safe therapeutic options for acute carotid blowout syndrome. Embolization for ICA/CCA carotid blowout syndrome was associated with higher risks of procedural stroke and lower recurrent bleeding compared to stent grafts.


Asunto(s)
Enfermedades de las Arterias Carótidas/terapia , Embolización Terapéutica/métodos , Procedimientos Endovasculares/métodos , Neoplasias de Cabeza y Cuello/cirugía , Disección del Cuello/efectos adversos , Stents , Enfermedad Aguda , Adulto , Anciano , Enfermedades de las Arterias Carótidas/etiología , Arteria Carótida Común/fisiopatología , Arteria Carótida Interna/fisiopatología , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Disección del Cuello/métodos , Estudios Observacionales como Asunto , Medición de Riesgo , Rotura Espontánea/etiología , Rotura Espontánea/terapia , Síndrome , Resultado del Tratamiento
4.
Comp Biochem Physiol B Biochem Mol Biol ; 140(4): 635-46, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15763519

RESUMEN

To investigate the control at the mRNA level of glycogen metabolism in the cupped oyster Crassostrea gigas, we report in the present paper the cloning and characterization of glycogen phosphorylase and synthase cDNAs (Cg-GPH and Cg-GYS, respectively, transcripts of main enzymes for glycogen use and storage), and their first expression profiles depending on oyster tissues and seasons. A strong expression of both genes was observed in the labial palps and the gonad in accordance with specific cells located in both tissues and ability to store glucose. Cg-GPH expression was also found mainly in muscle suggesting ability to use glycogen as readily available glucose to supply its activity. For seasonal examinations, expression of Cg-GYS and Cg-GPH genes appeared to be regulated according to variation in glycogen content. Relative levels of Cg-GYS transcripts appeared highest in October corresponding to glycogen storage and resting period. Relative levels of Cg-GPH transcripts were highest in May corresponding to mobilization of glycogen needed for germ cell maturation. Expression of both genes would likely be driven by the oyster's reproductive cycle, reflecting the central role of glycogen in energy storage and gametogenic development in C. gigas. Both genes are useful molecular markers in the regulation of glycogen metabolism and reproduction in C. gigas but enzymatic regulation of glycogen phosphorylase and synthase remains to be elucidated.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Glucógeno Fosforilasa/genética , Glucógeno Sintasa/genética , Ostreidae/enzimología , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Glucógeno Fosforilasa/aislamiento & purificación , Glucógeno Sintasa/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , Estaciones del Año , Alineación de Secuencia , Distribución Tisular
5.
Gene ; 236(2): 221-30, 1999 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-10452942

RESUMEN

Nm23 is a gene family encoding different isoforms of the nucleotide diphosphate kinase (NDPK), an enzyme involved in the synthesis of nucleoside triphosphates. In the present study, the organization and expression of the nm23-M1 gene encoding the mouse NDPKA isoform are described. This gene is about 10kb long and composed of five exons. The organization and the exon-intron boundaries are strictly conserved as compared to the human and rat related genes. The gene promoter region did not exhibit any consensus TATA box, SP1 binding element or Inr sequence. By contrast, TCF-1/LEF-1 binding elements and Pit-1 consensus sequence were present. Northern blotting and in situ hybridization methods were carried out in adult and 18.5 days post-coitum (dpc) mouse embryo, respectively. They showed tissue-specific expression of nm23-M1 transcripts, despite housekeeping gene promoter features. The strongest signals were detected in the nervous system, sensory organs and embryonic thymus. In contrast nm23-M2 mRNA was shown to be more widely expressed.The relationship between nm23-M1 gene tissue-specific expression and the putative binding element of the promoter region is discussed.


Asunto(s)
Proteínas de Unión al GTP Monoméricas , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Animales , Mapeo Cromosómico , Exones , Biblioteca Genómica , Hibridación in Situ , Mucosa Intestinal/embriología , Ratones , Ratones Endogámicos C57BL , Modelos Genéticos , Nucleósido Difosfato Quinasas NM23 , Nucleósido-Difosfato Quinasa/genética , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Timo/embriología , Distribución Tisular , Factores de Transcripción/análisis , Transcripción Genética
6.
Gene ; 296(1-2): 87-97, 2002 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-12383506

RESUMEN

The nm23 gene family is thought to be involved in physiopathological processes such as growth, differentiation and cancer promotion, progression or metastasis. We report here the mouse nm23-M3 and nm23-M4 complementary DNA sequences and the genomic cloning, characterization and tissue expression pattern of the nm23-M2, nm23-M3 and nm23-M4 genes, in comparison with their human and rat orthologs and with the human nm23-H1 and mouse nm23-M1 genes. The organization and structure of the members of this gene family are remarkably similar in human and rodents. Accordingly, the striking similarities between the human and mouse nm23 genes enable the use of mouse transgenic and knock-out models for studying the role of nucleoside diphosphate kinase isoforms in human physiopathology.


Asunto(s)
Proteínas de Unión al GTP Monoméricas/genética , Nucleósido-Difosfato Quinasa/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Northern Blotting , Clonación Molecular , ADN/química , ADN/genética , ADN Complementario/química , ADN Complementario/genética , Embrión de Mamíferos/enzimología , Embrión de Mamíferos/metabolismo , Exones , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Genes/genética , Humanos , Hibridación in Situ , Intrones , Isoenzimas/genética , Ratones , Datos de Secuencia Molecular , Nucleósido Difosfato Quinasas NM23 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Sitio de Iniciación de la Transcripción
7.
J Endocrinol ; 103(2): 147-53, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6238117

RESUMEN

The uropygial gland of the male quail is a sebaceous-like, androgen-dependent structure. The waxes secreted by this gland consist of fatty acids esterified by alkane-2,3-diols. In adult male quail the relative concentrations of all fatty acids were not affected by castration and testosterone treatment; but in contrast, the relative concentration of dodecane diol was found to be correlated with the androgen levels. In castrated quail administration of testosterone induced an increase in the dodecane diol percentage which was blocked by protein-synthesis inhibitors. Furthermore, the effects of testosterone were found to be neutralized by the administration of cyproterone acetate. Consequently it may be stated that the relative concentration of dodecane diol is indeed a very good marker for androgenicity in the uropygial gland of the male quail. This experimental model seems well suited for evaluating the stimulators and inhibitors of the activity of the sebaceous gland.


Asunto(s)
Coturnix/fisiología , Metabolismo de los Lípidos , Codorniz/fisiología , Glándulas Sebáceas/metabolismo , Testosterona/farmacología , Ceras/metabolismo , Animales , Cloaca/anatomía & histología , Cloaca/efectos de los fármacos , Cicloheximida/farmacología , Ciproterona/análogos & derivados , Ciproterona/farmacología , Acetato de Ciproterona , Dactinomicina/farmacología , Aseo Animal , Luz , Masculino , Tamaño de los Órganos/efectos de los fármacos , Puromicina/farmacología , Glándulas Sebáceas/efectos de los fármacos
8.
J Endocrinol ; 109(3): 299-306, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3734664

RESUMEN

An exchange assay for androgen receptors in the quail uropygial gland using [3H]mibolerone was established. The most efficient exchange conditions were 3 days of incubation at 15 degrees C. Under these conditions, androgen receptors were stable in the presence of sodium molybdate, and the exchange of [3H]mibolerone with endogenous testosterone bound to cytosolic or nuclear androgen receptors was maximal. Less than 5% of [3H]mibolerone-binding sites occurred in the extracted nuclear pellets. Using this exchange technique, it was shown that androgen receptors in the uropygial gland of photostimulated male quail or castrated quail treated with testosterone were activated and that their concentrations in both cytosolic and nuclear fractions were increased. These results confirm the androgen dependency of the quail uropygial gland, and show that it is an organ which can be used as a model for the study of androgen action in sebaceous glands.


Asunto(s)
Receptores Androgénicos/metabolismo , Glándulas Sebáceas/metabolismo , Testosterona/farmacología , Animales , Núcleo Celular/metabolismo , Coturnix , Citosol/metabolismo , Luz , Masculino , Modelos Biológicos , Nandrolona/análogos & derivados , Nandrolona/farmacología , Orquiectomía , Periodicidad , Ensayo de Unión Radioligante , Glándulas Sebáceas/efectos de los fármacos , Testosterona/sangre , Congéneres de la Testosterona/farmacología
9.
Placenta ; 25(1): 20-8, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15013635

RESUMEN

NDP kinases are the non-specific enzymes which catalyse the synthesis of the NTPs through a transfer reaction using ATP as phosphoryl donor. In addition to their enzymatic activity, they display other not yet explained functions related to cell growth, differentiation and apoptosis, embryonic development, tumour progression and metastasis. In this study, the expression patterns of the three highly related NDP kinases A, B and C isoforms were investigated in the developing human trophoblast. Both NDP kinase A and B were found to be primarily present in the villous and extravillous cytotrophoblasts, while NDP kinase C was found almost exclusively in the syncytiotrophoblast layer. This suggests that NDP kinase A and B could be a marker for the mononuclear stage of differentiation of villous trophoblasts, while NDP kinase C could be a marker of the syncytiotrophoblast layer.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Nucleósido-Difosfato Quinasa/genética , Trofoblastos/enzimología , Desarrollo Embrionario y Fetal/fisiología , Proteínas del Ojo/metabolismo , Femenino , Edad Gestacional , Humanos , Inmunohistoquímica , Hibridación in Situ , Antígeno Ki-67/análisis , Nucleósido Difosfato Quinasas NM23 , Proteínas del Tejido Nervioso/metabolismo , Nucleósido-Difosfato Quinasa/metabolismo , Embarazo
10.
Brain Res Mol Brain Res ; 63(2): 351-65, 1999 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-9878823

RESUMEN

Nm23 has been identified as a gene family encoding different isoforms of the nucleoside diphosphate kinase. This protein is a key enzyme in the control of cellular concentrations of nucleoside triphosphates. Moreover, it has been shown to play important roles in various cellular functions such as differentiation and metastasis. In the present study, a second cDNA for nucleoside diphosphate kinase A (Nm23-M1) was isolated from a cDNA library of mouse embryonic stem cells. This clone encodes the same putative 152 aminoacids long protein as an already published cDNA but is longer in both its 5' and 3' untranslated regions. Tissue and cellular distribution of nm23-M1 mRNA was investigated by using Northern blot analysis and in situ hybridization. Nm23-M1 transcripts were found to be widely distributed throughout the mouse central nervous system with prominent expression in several restricted areas. No differences were noticed between the distribution of long and short transcripts. Furthermore, a similar pattern of expression was described in the central nervous system for nm23-M2 mRNA, encoding a second isoform of the nucleoside diphosphate kinase. However, the transcript of this isoform displayed a wider distribution and was expressed in all organs analysed by northern blotting. The possible involvement of nm23-M1 in differentiation of mouse nervous system is further discussed.


Asunto(s)
Sistema Nervioso Central/metabolismo , ADN Complementario/genética , Proteínas de Unión al GTP Monoméricas , Proteínas del Tejido Nervioso/genética , Nucleósido-Difosfato Quinasa/genética , Isoformas de Proteínas/genética , Factores de Transcripción/genética , Animales , Secuencia de Bases , Northern Blotting , Células Cultivadas , Clonación Molecular , Hibridación in Situ , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Familia de Multigenes , Nucleósido Difosfato Quinasas NM23
11.
Fertil Steril ; 62(3): 648-50, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8062966

RESUMEN

In the light of the newly discovered implications of human interleukin for DA cells and leukemia inhibitory factor in embryology, we searched for the presence of this soluble cytokine in the supernatant of Vero cell coculture systems. Using a bioassay as well as a specific ELISA, we demonstrated that Vero cells are able to release large quantities of human interleukin for DA cells and leukemia inhibitory factor in the embryo-growing medium of such cocultures.


Asunto(s)
Inhibidores de Crecimiento/metabolismo , Interleucina-6 , Linfocinas/metabolismo , Células Vero/metabolismo , Animales , Bioensayo , Células Cultivadas , Chlorocebus aethiops , Medios de Cultivo/metabolismo , Técnicas Citológicas , Embrión de Mamíferos/citología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Factor Inhibidor de Leucemia , Masculino , Ratones
12.
Steroids ; 43(4): 363-9, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6523549

RESUMEN

In adult male ducks submitted to marked variations in plasma testosterone concentration, plasma transcortin (CBG) levels were shown to be closely related to the level of plasma testosterone. In connection with previous data on female ducks, the results strongly support the evidence that at least in this species, CBG is under a stimulatory control by testosterone.


Asunto(s)
Testosterona/sangre , Transcortina/metabolismo , Animales , Castración , Patos , Femenino , Masculino , Testosterona/farmacología
13.
Steroids ; 38(1): 29-34, 1981 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7292539

RESUMEN

Corticosteroid binding globulin (CBG) serum level as evaluated by either equilibrium dialysis or gel filtration was found to be higher in male than in female adult ducks during the reproductive period. Castration did not modify CBG concentrations in females, whereas in males it induced a significant decreased in CBG, to the level observed in intact or castrated females. Testosterone injections administrated to castrated females increased CBG to the level of adult intact males. Finally it was found that testosterone stimulated CBG production in ducks without altering thyroxine levels.


Asunto(s)
Patos/fisiología , Transcortina/análisis , Animales , Castración , Cromatografía en Gel , Diálisis , Femenino , Masculino , Estaciones del Año , Caracteres Sexuales , Testosterona/farmacología , Tiroxina/sangre
14.
Steroids ; 30(5): 703-9, 1977 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-611636

RESUMEN

Androgen receptors have been found in duck preen glands by using dextran-coated charcoal adsorption. They bound DHT with high affinity (KD = 0.2 nM), limited capacity (45 fmoles/mgP) and good specificity. They sedimented at 8 S in a sucrose gradient and were destroyed by pronase digestion and heating. An estrogen receptor having different binding specificity was also demonstrated. On the basis of a marked annual cycle of gonadal activity in ducks, this system appears appropriate for studying the regulation of sex steroid hormone receptors.


Asunto(s)
Patos/metabolismo , Receptores Androgénicos/aislamiento & purificación , Receptores de Estrógenos/aislamiento & purificación , Receptores de Esteroides/aislamiento & purificación , Glándulas Sebáceas/análisis , Adsorción , Animales , Sitios de Unión , Centrifugación por Gradiente de Densidad , Carbón Orgánico , Citosol/análisis , Citosol/metabolismo , Dihidrotestosterona/metabolismo , Estradiol/metabolismo , Técnicas In Vitro , Masculino , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Glándulas Sebáceas/citología , Glándulas Sebáceas/metabolismo
15.
Steroids ; 55(5): 228-32, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2360219

RESUMEN

The metabolism of DHT in the cytosol of the quail uropygial gland was found to be so high that the steroid was almost completely inactivated within 2 hours of incubation at 0 C. In these conditions, DHT cannot be used for the characterization of androgen receptors. By contrast, R 1881 and mibolerone, which are not metabolized, can be used as alternative ligands. Moreover, the extremely high metabolism of DHT questions the physiologic role of this steroid in the quail uropygial gland.


Asunto(s)
Citosol/metabolismo , Dihidrotestosterona/metabolismo , Codorniz/metabolismo , Glándulas Sebáceas/metabolismo , Animales , Masculino , Metribolona/metabolismo , Nandrolona/análogos & derivados , Nandrolona/metabolismo , Receptores Androgénicos/metabolismo , Testosterona/metabolismo , Congéneres de la Testosterona/metabolismo
16.
Steroids ; 45(5): 391-401, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3834658

RESUMEN

The metabolism of testosterone in the uropygial gland of the quail principally results in the production of 17 alpha, 5 beta derivatives. Moreover, an unusually small amount of testosterone is converted to 5 alpha-dihydrotestosterone. These results question the role played by intracellular 5 alpha-reduction in the response of the gland to testosterone stimulation.


Asunto(s)
Glándulas Exocrinas/metabolismo , Codorniz/metabolismo , Testosterona/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/metabolismo , Animales , Dihidrotestosterona/biosíntesis , Dihidrotestosterona/aislamiento & purificación , Epitestosterona/biosíntesis , Cromatografía de Gases y Espectrometría de Masas , Masculino , NADP/metabolismo
17.
Mar Biotechnol (NY) ; 5(4): 360-72, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14719164

RESUMEN

Using the previously determined complementary DNA Sequence of Crassostrea gigas amylase (Y08370), we designed several oligonucleotide primers and used them with polymerase chain reaction (PCR) technology to characterize oyster amylase gene sequences. Two genes encoding 2 different amylases were characterized and sequenced. The 2 genes are similarly organized with 8 exons and 7 introns. Intron insertions are found at the same location in the 2 genes. Sizes and nucleotide sequences are different for the different introns inside each gene and different for the corresponding introns in the 2 genes. Comparing the 2 genes, around 10% of the nucleotides are different along the exons, and comparing the 2 deduced protein sequences, a mean value of 10.4% of amino acids are changed. Genes A and B encode mature proteins of, respectively, 500 and 499 amino acids, which present 94% similarity. A microsatellite (TC(37)) that constitutes the largest part of intron 4 of gene A has been used as a polymorphic marker. A method consisting of a PCR step followed by EcoRI digestion of the obtained fragments was used to observe polymorphism in these 2 genes. Six and 4 alleles for genes A and B, respectively, have been sequenced, leading to a maximum of 2.9% base change. The 2 genes are ubiquitously expressed in the different digestive tissues with quantitative differences. Gene A is strongly expressed in the digestive gland and at a lower level in stomach, while gene B is preferentially expressed in the labial palps. The microsatellite repeat was used in the analysis of 4 populations of Crassostrea gigas from the French Atlantic coast. A high level of polymorphism observed with 30 different alleles of gene A inside the populations should allow their characterization using the mean value of the microsatellite allelic distribution. These populations showed a low level of differentiation ( F(st) between 0 and 0.011); however, the population of Bonne Anse appeared to be distinguished from the other populations.


Asunto(s)
Alelos , Amilasas/genética , Genética de Población , Ostreidae/genética , Polimorfismo Genético , Animales , Secuencia de Bases , Mapeo Cromosómico , Cartilla de ADN , ADN Complementario/genética , Francia , Perfilación de la Expresión Génica , Frecuencia de los Genes , Datos de Secuencia Molecular , Polimorfismo de Longitud del Fragmento de Restricción , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN
18.
Comp Biochem Physiol B Biochem Mol Biol ; 163(1): 96-100, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22580267

RESUMEN

In the oyster Crassostrea gigas consumption-related traits, amylase properties and growth were found to be linked through genotypes that differed for polymorphism in the two amylase genes AMYA and AMYB. Modulation of AMYA mRNA level had already been observed in response to food availability, whereas the functional role of AMYB was still unknown. To improve knowledge about the regulation of amylase expression in C. gigas and the respective roles of the two genes, we made an assay of amylase expression at mRNA and enzymatic levels in the digestive gland of oysters that had received dietary supplements of starch. After 18 days, a significant increase of translatable mRNA for AMYB was observed, with a correlated increase in Michaelis-Menten constant Km values and a decrease in total amylase activity. This modulation is the first evidence of observable functioning of AMYB in digestive processes. Amylase B is suggested to display a higher Km than amylase A, offering a means of adapting to high substrate concentrations. The highest starch supplement level (10 mgL(-1)) induced alteration in oyster physiology. The 1 mgL(-1) treatment should be tested as a practical food supplement that could lead to growth benefits for oysters.


Asunto(s)
Amilasas/genética , Amilasas/metabolismo , Crassostrea/enzimología , Almidón/farmacología , Animales , Crassostrea/efectos de los fármacos , Crassostrea/genética , Activación Enzimática/efectos de los fármacos , Activación Enzimática/genética , ARN Mensajero/genética
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