Search results for " Sea Urchin"
showing 10 items of 102 documents
Formulazione di un mangime altamente performante per l’acquacoltura di specie erbivore ed onnivore
2010
Crushing predation of the spiny star Marthasterias glacialis upon the sea urchin Paracentrotus lividus
2009
Literature data report that only fish predators are able to crush sea urchin tests in Mediterranean rocky reefs. This experimental study showed that the spiny star Marthasterias glacialis is able to break Paracentrotus lividus tests and that the breaking event is more likely to occur for small-sized sea urchins than for big ones. Our results show that the role of M. glacialis in regulating P. lividus population density can be important in specific locations. They may have important implications, moreover, for the use of tethering techniques aimed at identifying predator types of sea urchins.
Climate change potentially affect keystone predation in subtidal system.
2014
Metallothionein genes in sea urchin embryos and their induction by cadmium
2012
Metallothioneins (MTs) are proteins that play a major role in metal homeostasis and as a reservoir. The MT gene/protein systems of sea urchins are an invaluable model for the study of gene expression regulation and MT isoform-specific functionality of these proteins. We isolated five paralogous MT isogenes and we studied their expression in the sea urchin embryo Paracentrotus lividus. The Cadmium-dependent transcriptional activation of the five isogenes was assessed using quantitative Real Time PCR. Two of the five P. lividus MT (MT-7 and MT-8) isogenes appeared to be constitutively expressed and upregulated upon cadmium treatment. Three isogenes (MT-4/MT-6) are not transcribed in control e…
Genome wide survey of the Toll-like receptor family in the Mediterranean sea urchin
Toll-like receptors (TLRs) represent a conserved family of proteins widely expressed in eukaryotes. They play crucial roles in the innate immune system recognizing different pathogen-associated molecular patterns. In mammals the TLR family comprises 10-13 members, while a huge number of TLR-like genes were recovered in S.purpuratus[1-3]. The Paracentrotus lividus genome project recently generated a new highquality assembly of the genome that represents a valuable resource also for clarifying the evolutionary origin of immune system. In order to identify TLR genes in P.lividus, a genome wide survey was carried out and BLAT searches retrieved 119 TLR genes (PlivTLRs). Ab initio gene predictio…
Spatially restricted expression of strim, a novel TRIM-containing gene, in the oral ectoderm of the developing sea urchin embryo Paracentrotus lividu…
2010
The recent wealth of genomic data has confirmed that bilaterians as simple as nematodes and as complex as humans use the same basic toolkit of transcription factors and signaling molecules to process spatial and temporal information during development (1,2). Among these regulators, the TRIM/RBCC (Tripartite motif/RING-Bbox-Coiled Coil) family represents one of the largest classes of putative E3 ubiquitin ligases that play essential roles in cell cycle regulation and development (3). It consists of rapidly evolving genes, identified in eukaryotic organisms (4,5). In the sea urchin Paracentrotus lividus we have identified a locus containing two copies, probably originated from a duplication e…
Enhancer, chromatin insulator, non-coding RNA and α-histone gene expression during embryogenesis of the sea urchin Paracentrotus lividus.
2009
Core promoters and chromatin insulators (ins) may direct a transcriptional enhancer (enh) to prefer a specific promoter in complex genetic loci. Enh and ins flank the sea urchin Paracentrotus lividus α-histone H2A transcription unit in a tandem repeated cluster containing the five histone genes. In vivo competition assays of enh and ins functions reveal that the H2A enh-bound MBF-1 activator participates also in the expression of the H3 gene and that the sns5 ins buffers the downstream H1 promoter from the H2A enh. These results suggest that both the H2A enh and the sns5 ins may account for the diverse accumulation of the linker vs core nucleosomal histones during early development of the s…
The sea urchin sns5 chromatin insulator settles a gene therapy vector into an independent domain of expression in the vertebrate genome
2014
One of the critical aspects of introducing a transgene into the eukaryotic genome is the great variability of gene expression due to position effects (1). Chromatin-dependent repressive states could be overcome by incorporation in the transgene of chromatin insulators, functioning to establish and delimit domains of expression. We have previously demonstrated that the sea urchin sns5 DNA element has the typical features of an insulator: by acting as enhancer blocker, it shields promoters from neighboring regulatory elements, and by acting as barrier it buffers a transgene from the propagation of condensed chromatin (2,3). We have investigated the use of sns5 in the field of gene therapy. Ou…
Suppression of nodal expression in prospective dorsal cells of the early sea urchin embryo by the hbox12 homeodomain regulator
2014
Dorsal/Ventral (DV) axis formation in the sea urchin embryo depends upon the expression of nodal on the ventral side, which behaves as a DV organizing centre. However, only fuzzy clues are known as to the early symmetry-breaking steps that lead to the positioning of such an organizer. An extremely interesting candidate for this role is the hbox12 homeobox-containing gene. In Paracentrotus lividus, hbox12 expression is antecedent and complementary with respect to that of nodal, being confined in prospective dorsal cells. We show that ectopic expression of Hbox12 provokes DV abnormalities and attenuates nodal as well as nodal-dependent gene transcription. By blastomere transplantation, we als…