RESUMEN
Nucleolar segregation is the most striking cellular phenotypic feature of cold-acclimatized carp and depicts the cyclical reprogramming that the physiology of the fish undergoes between summer and winter, where a clear differential expression of some nucleolar related genes occurs. We characterized carp nucleolin, a nucleolar protein involved in multiple steps of ribosome biogenesis, and evaluated its expression upon fish acclimatization. We show that the carp cDNA deduced amino acid sequence exhibits the same tripartite structural organization found in other species. Nevertheless, we observed that nucleolin mRNA expression was strongly induced in the cold-adapted carp as was the nuclear protein content, assessed by immunocytochemistry in liver sections. The physiological up-regulation of nucleolin in the cold-acclimatized carp, where rRNA transcription and processing are depressed concomitantly with the nucleolus segregation, is consistent with the notion that nucleolin plays a fundamental role in repressing rRNA synthesis.
Asunto(s)
Aclimatación/fisiología , Carpas/fisiología , Nucléolo Celular/metabolismo , Regulación de la Expresión Génica , Fosfoproteínas/metabolismo , Proteínas de Unión al ARN/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Encéfalo/citología , Encéfalo/metabolismo , Frío , ADN Complementario/genética , Hígado/citología , Hígado/metabolismo , Masculino , Datos de Secuencia Molecular , Fosfoproteínas/genética , Estructura Terciaria de Proteína , ARN Nucleolar Pequeño/genética , ARN Nucleolar Pequeño/metabolismo , Proteínas de Unión al ARN/genética , Proteínas Ribosómicas/genética , Proteínas Ribosómicas/metabolismo , Estaciones del Año , NucleolinaRESUMEN
We isolated and cloned a carp somatolactin SL DNA fragment, of which 78% of the nucleotides were identical to the corresponding salmon SL sequence. The results obtained upon Northern blot hybridization of carp pituitary RNA allowed the identification of two transcripts as described for other fish. When the content of SL transcripts in pituitary sections from summer- and winter-acclimatized carp was quantified by in situ hybridization assays, we found no significant differences between the two seasons. In salmonids, plasma SL reaches higher levels in summer than in winter in synchrony with the water temperature cycle; in the eurythermal carp, however, the complex adaptive responses imposed by seasonal environmental changes do not seem to include the regulation of the somatolactin detected with the probe used at the transcriptional level in pituitary glands.
Asunto(s)
Carpas/fisiología , Glicoproteínas/genética , Hibridación in Situ/métodos , Hipófisis/fisiología , Hormonas Hipofisarias/genética , Transcripción Genética , Aclimatación/fisiología , Animales , Secuencia de Bases , Northern Blotting , Fragmentación del ADN , Proteínas de Peces , Glicoproteínas/aislamiento & purificación , Hormonas Hipofisarias/aislamiento & purificación , Salmón , Estaciones del AñoRESUMEN
The dramatic segregation of the nucleolar components in winter-acclimatized carp is the most striking cellular-phenotypical feature observed during the seasonal adaptation of this fish toward the circannual changes in its habitat. Our studies also show that the carp habitat temperature and photoperiod winter conditions provoke a remarkable reduction of both rRNA transcription and the processing of their precursors. To gain knowledge on the mechanisms involved in the regulation of nucleolar activity during the seasonal adaptation process, we studied the behavior of some genes, specifically snoRNA U3 and protein kinase CK2. Consistent with the reduction in the synthesis and processing of pre-rRNA observed during the cold season, the level of CK2beta expression decreases in winter when compared to that attained in summer. Similarly, in winter, liver and kidney cells contain lower levels of CK2beta subunit protein compared to summer. CK2 is associated with or modifies different factors and enzymes involved in the nucleolar activity; therefore, its higher or lower content could be part of the molecular mechanisms underlying the nucleolar seasonal changes that occur during the compensatory acclimatization process.
Asunto(s)
Carpas/genética , Carpas/metabolismo , Regulación Enzimológica de la Expresión Génica , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Serina-Treonina Quinasas/genética , Animales , Western Blotting , Quinasa de la Caseína II , Nucléolo Celular/metabolismo , Núcleo Celular/enzimología , ADN Complementario/metabolismo , Inmunohistoquímica , Riñón/enzimología , Luz , Hígado/enzimología , Masculino , Modelos Moleculares , Péptidos/química , Unión Proteica , Estructura Terciaria de Proteína , Estaciones del Año , TemperaturaRESUMEN
Ethical issues pertaining research and counseling in nutritional sciences will be arising in this new century. This issue will be of great importance especially in the area of nutraceutical supplementation and disease (pharmacological nutrition). Steps to insure bioethical correctness are discussed in this paper.
Asunto(s)
Consejo , Suplementos Dietéticos , Dietética/normas , Ética Profesional , Fenómenos Fisiológicos de la Nutrición , Dietética/tendencias , Predicción , Humanos , InvestigaciónRESUMEN
Carp fish seasonal acclimatization induces a cyclical transcriptional modulation of several genes. Its most dramatic expression results in a concomitant structural rearrangement of the nucleolar components that phenotypically represents profound shifts in the level of ribosomal RNA synthesis. In connection with the recent studies that implicate CK2 in the control of rRNA synthesis in vertebrates, we characterized the cDNA of carp protein kinase CK2beta subunit and assessed its transcriptional behavior in winter- and summer-acclimatized fish. We found a remarkable differential gene expression of CK2beta subunit between summer- and winter-acclimatized carp which correlates with the modulatory pattern observed in rRNA transcription.
Asunto(s)
Aclimatación/fisiología , Carpas/fisiología , Proteínas Serina-Treonina Quinasas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Quinasa de la Caseína II , Línea Celular , Clonación Molecular , Regulación Enzimológica de la Expresión Génica , Hibridación in Situ , Riñón/enzimología , Hígado/enzimología , Datos de Secuencia Molecular , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/metabolismo , ARN Ribosómico/genética , Estaciones del Año , Alineación de SecuenciaRESUMEN
The use of alternative/complementary medicine has been increasing considerably. Conventional medicine must begin to address issues related to the use, safety, regulation, research and education of alternative/complementary medicine. Integrative medicine combines conventional medicine and alternative complementary practices. Integrative medicine is an innovative approach to medicine and medical education. It involves the understanding of the interaction of the mind, body and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from disease based approach to a healing based approach. It does not reject conventional medicine nor uncritically accepts unconventional practices. Integrative medicine is an effective, more fulfilling human approach to medicine based on the benefit of the patient by following good medicine practices in a scientific manner.
Asunto(s)
Terapias Complementarias/educación , Prestación Integrada de Atención de Salud/tendencias , Educación Médica/tendencias , Salud Holística , Humanos , Puerto RicoRESUMEN
A second Pit-1 gene in carp (Cyprinus carpio), including the complete structural gene and 1.1 kb of promoter region, was identified and completely sequenced. The exon-intron structure was determined, and reverse transcription-polymerase chain reaction (RT-PCR) experiments suggest that only one Pit-1 splice variant is present in carp pituitary. The effect of seasonal acclimatization on the extent of Pit-1 gene expression was studied in summer- and winter-acclimatized carp. Quantitative RT-PCR analysis revealed a clear increase of Pit-1 mRNA in the pituitaries from summer-acclimatized carp compared with the winter-adapted fish. In situ hybridization of pituitary gland sections with riboprobes representing the complete 5'-transactivating region of carp Pit-1 depicted a significantly higher Pit-1 mRNA level in the rostral pars distalis of the summer-acclimatized fish where prolactin is expressed in a manner that resembles the seasonal increase observed in the proximal pars distalis and the pars intermedia. The cell- and temporal-specific transcription of Pit-1 supports its role in the molecular mechanisms that underly the acclimatization process undergone by eurythermal fish as a result of the physical effects of seasonal changes on their habitat.
Asunto(s)
Carpas/genética , Carpas/metabolismo , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Hipófisis/metabolismo , Estaciones del Año , Factores de Transcripción/biosíntesis , Factores de Transcripción/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Duplicación de Gen , Expresión Génica , Proteínas de Homeodominio/biosíntesis , Proteínas de Homeodominio/genética , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Temperatura , Factor de Transcripción Pit-1RESUMEN
We isolated a clone comprising four exons of the carp Pit-1 gene. Using synthetic oligonucleotide probes derived from the carp Pit-1 sequence Pit-1 expression was assessed by in situ hybridization in pituitary sections from summer- and winter-acclimatized carp. Semiquantitative analyses of the hybridization signals revealed a significant higher Pit-1 expression in the proximal pars distalis (PPD) and pars intermedia (PI) of the pituitary glands from summer-acclimatized carp, compared to the winter-acclimatized fish. In both adaptive states, relative to the PPD and PI, only a basal Pit-1 expression was detected in the rostral pars distalis. Thus, during seasonal acclimatization of an eurythermal fish, Pit-1 seems to be involved in the mechanisms that underlie the compensatory response.