Search results for "sea urchin."
showing 10 items of 317 documents
Functional variants of 5S rRNA in the ribosomes of common sea urchin Paracentrotus lividus
2012
Abstract We have previously reported a molecular and cytogenetic characterization of three different 5S rDNA clusters in the sea urchin Paracentrotus lividus ; this study, performed at DNA level only, lends itself as starting point to verify that these clusters could contain transcribed genes, then, to demonstrate the presence of heterogeneity at functional RNA level, also. In the present work we report in P. lividus ribosomes the existence of several transcribed variants of the 5S rRNA and we associate all transcribed variants to the cluster to which belong. Our finding is the first demonstration of the presence of high heterogeneity in functional 5S rRNA molecules in animal ribosomes, a f…
Effects of cadmium exposure on sea urchin development assessed by SSH and RT-qPCR: metallothionein genes and their differential induction
2012
In order to study the defense strategies activated by Paracentrotus lividus embryos in response to sub-lethal doses of CdCl2, we compared the induced transcripts to that of control embryos by suppression subtractive hybridization technique. We isolated five metallothionein (MT) cDNAs and other genes related to detoxification, to signaling pathway components, to oxidative, reductive and conjugative biotransformation, to RNA maturation and protein synthesis. RT-qPCR analysis revealed that two of the five P. lividus MT (PlMT7 and PlMT8) genes appeared to be constitutively expressed and upregulated following cadmium treatment, whereas the other three genes (PlMT4, PlMT5, PlMT6) are specifically…
Inhibitor of the Cytochrome Oxidase of Unfertilized Sea Urchin Eggs
1960
IN a previous communication1 the presence of an inhibitor of cytochrome oxidase in the unfertilized sea urchin egg was described. It was shown that its activity decreases considerably following fertilization, that it is a low-molecular compound, that it is heat- and alkali-labile and that its action is of a competitive type.
Different mRNA localization patterns for metallothioneins (MTs) during embryo development
MTs play pivotal roles in physiological and redox homeostasis. They are also essential during embryo development of P. lividus sea urchin. At least five MT genes are expressed in P. lividus embryo. MT7 and MT8 are constitutively expressed; while, MT4, 5, and 6 are considered as metal-induced homologues. Whole mount in situ hybridization (WMISH) defined the MT mRNAs localization across the embryo territories of the sea urchin. At the gastrula stage, MT7 is localized principally in the endomesoderm, in the vegetal pole. Progressively, it becomes heavily expressed in the endoderm during archenteron specialization in midgut and hindgut and then in stomach and intestine at the pluteus stage. In …
Localization of mitochondrial Hsp56 chaperonin during sea urchin development.
2001
We have previously demonstrated that Paracentrotus lividus nuclear genome encodes for the heat shock inducible chaperonin homolog Hsp 56 (1) and that the mature protein is localized in the mitochondrial matrix (2). In this paper we report that constitutive Hsp56 is maternally inherited, in fact it is present in the in unfertilized eggs, and that it has a perinuclear specific localization during cleavage. In the later stages both the constitutive and the heat shock inducible chaperonin has a specific territorial distribution. Moreover following heat shock, the Hsp56 appears in the cytoplasm and in the postmitochondrial supernatant beside the mitochondrial fraction.
Vanadium Modulates Proteolytic Activities and MMP-14-Like Levels during Paracentrotus lividus Embryogenesis
2022
The increasing industrial use of vanadium (V), as well as its recent medical use in various pathologies has intensified its environmental release, making it an emerging pollutant. The sea urchin embryo has long been used to study the effects induced by metals, including V. In this study we used an integrated approach that correlates the biological effects on embryo development with proteolytic activities of gelatinases that could better reflect any metal-induced imbalances. V-exposure caused morphological/morphometric aberrations, mainly concerning the correct distribution of embryonic cells, the development of the skeleton, and the embryo volume. Moreover, V induced a concentration change …
STUDIO DELLA BIODISTRIBUZIONE DI SOSTANZE BIOLOGICAMENTE ATTIVE IN ORGANISMI ACQUATICI
2022
The nucleus negatively controls the synthesis of mitochondrial proteins in the sea urchin egg.
1983
Enucleation of Paracentrotus lividus eggs, followed by parthenogenetic activation induces a sharp increase in the synthesis of mitochondrial proteins as shown by electrofluorography after in vivo labeling with radioactive amino acids. These results further substantiate the hypothesis that the cell nucleus negatively controls mitochondrial replication in the sea urchin egg.
Controlled uptake of PFOA in adult specimens of Paracentrotus lividus and evaluation of gene expression in their gonads and embryos
2023
AbstractPerfluorooctanoic acid (PFOA) has been largely used in the manufacturing industry but a few years ago it turned out to be a dangerous pollutant which is now of concern for terrestrial and aquatic environments. Here, we investigated the bioaccumulation of PFOA in the sea urchin Paracentrotus lividus after exposure to different concentrations of the pollutant for 28 days. We observed rapid uptake of PFOA in the coelomic fluid collected weekly during the exposure period and high bioaccumulation in gonads at the end of the experiment. Interestingly, animals were also able to fast depurate when relocated to a clean environment. In addition, to assess the effect of PFOA on sea urchins’ ph…
On the incorporation of S35-methionine in artificially activated sea urchin eggs
1958
Metionina-S35 e stata incorporata in uova vergini diParacentrotus lividus. In queste l'isotopo si trova per la piu gran parte nella frazione solubile in acido tricloracetico al 10%. Attivando le uova partenogeneticamente con acido butirrico si osserva una progressiva perdita di attivita di questa frazione ed una rapida incorporazione nei mitocondri. L'andamento del fenomeno e del tutto identico a quello gia descritto (Nakano eMonroy) nelle uova normalmente fecondate.