Search results for "sea urchins"

Antimicrobial and Antibiofilm Activity of a Recombinant Fragment of β-Thymosin of Sea Urchin Paracentrotus lividus

2018

With the aim to obtain new antimicrobials against important pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa, we focused on antimicrobial peptides (AMPs) from Echinoderms. An example of such peptides is Paracentrin 1 (SP1), a chemically synthesised peptide fragment of a sea urchin thymosin. In the present paper, we report on the biological activity of a Paracentrin 1 derivative obtained by recombination. The recombinant paracentrin RP1, in comparison to the synthetic SP1, is 22 amino acids longer and it was considerably more active against the planktonic forms of S. aureus ATCC 25923 and P. aeruginosa ATCC 15442 at concentrations of 50 &micro

Sequence of a sea urchin hsp70 gene and its 5' flanking region.

1990

We report the nucleotide sequence of a 4470-bp fragment derived from a sea urchin genomic clone containing part of a heat-shock protein 70 (Hsp70)-encoding gene. This fragment, named hsp70 gene II, contains 1271 bp of the flanking region and 3299 bp of structural gene sequence interrupted by five introns and encoding the N-terminal 371 amino acids (aa) of the protein. The 5' flanking region contains a putative TATA element, two CCAAT boxes, four heat-shock consensus sequence elements (hse) and one consensus sequence for binding of Sp1. Remarkable homologies were observed for deduced aa sequence and intron-exon organization between hsp70 gene II and rat hsc73 gene.

On the adenosintriphosphatase activity of the particulates of the egg of the sea urchinParacentrotus lividus

1957

I particolati delle uova vergini di riccio di mare possono essere separati, a mezzo della centrifugazione differenziale, in due frazioni, una fortemente ed una scarsamente pigmentata. La prima mostra una attivita ATPasica attivata da Mg con un massimo a pH 8.2; il massimo della seconda e invece a pH 6.4. Nelle preparazioni contenenti i due tipi di particolati si ritrovano i due massimi.

Toxicological Impact of Rare Earth Elements (REEs) on the Reproduction and Development of Aquatic Organisms Using Sea Urchins as Biological Models

2022

The growing presence of lanthanides in the environment has drawn the attention of the scientific community on their safety and toxicity. The sources of lanthanides in the environment include diagnostic medicine, electronic devices, permanent magnets, etc. Their exponential use and the poor management of waste disposal raise serious concerns about the quality and safety of the ecosystems at a global level. This review focused on the impact of lanthanides in marine organisms on reproductive fitness, fertilization and embryonic development, using the sea urchin as a biological model system. Scientific evidence shows that exposure to lanthanides triggers a wide variety of toxic insults, includi…

Correction to: Echinodermata: The complex immune system in echinoderms (Advances in Comparative Immunology, 10.1007/978-3-319-76768-0_13)

2018

This chapter was inadvertently published with an incorrect spelling of the author's name as V. Arriza whereas it should be V. Arizza. In addition to this the affiliation of one of the chapter authors Elisse Sutton was published incorrectly and it has now been corrected to read as Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.

Influenza della protezione sulla struttura dei popolamenti algali dell’AMP “Isola di Ustica”, un caso di studio.

2008

“BEP” RNAs and Proteins Are Situated in the Animal Side of Sea Urchin Unfertilized Egg, Which Can Be Recognized by Female Pronuclear Localization

1996

Microsurgery experiments demonstrate that the animal side of the unfertilized sea urchin Paracentrotus lividus egg coincides with the side of the egg pronucleus location. It is demonstrated by means of in situ hybridization and immunostaining of whole mounts of animal or vegetal halves that the previously identified bep 1 and bep4 RNAs and their proteins are located in the animal part of the unfertilized egg and much less in the vegetal part. The addition of Fabs against BEP1 and BEP4 causes exogastrulation.

Specific expression of a TRIM-containing factor in ectoderm cells affects the skeletal morphogenetic program of the sea urchin embryo

2011

In the indirect developing sea urchin embryo, the primary mesenchyme cells (PMCs) acquire most of the positional and temporal information from the overlying ectoderm for skeletal initiation and growth. In this study, we characterize the function of the novel gene strim1, which encodes a tripartite motif-containing (TRIM) protein, that adds to the list of genes constituting the epithelial-mesenchymal signaling network. We report that strim1 is expressed in ectoderm regions adjacent to the bilateral clusters of PMCs and that its misexpression leads to severe skeletal abnormalities. Reciprocally, knock down of strim1 function abrogates PMC positioning and blocks skeletogenesis. Blastomere tran…

The dynamics of structural modifications of mitochondria at the early stages of sea urchin embryonic development

1992

The organization of the chondriome and the ultrastructure of mitochondria have been studied in eggs and embryos of the sea urchin Paracentrotus lividus. The egg chondriome is characterized by an arrangement in well-delimited clusters. Analysis of mitochondrial clusters on electron micrographs of ultrathin serial sections shows two kinds of mitochondria of different shapes, the rod-shaped and the spherical. The egg mitochondria have a dense matrix and a well-ordered arrangement of cristae which, in rod-shaped variety, are perpendicular to the major axis. Cell division is accompanied by significant changes in intracellular distribution of mitochondria and in their structure. At the stage of 2…

Expression of homeobox-containing genes in the sea urchin (Parancentrotus lividus) embryo

1994

Two homeobox-containing genes that belong to different homeodomain classes have been isolated from a sea urchin geonomic library. One, PlHbox11, is the sea urchin homologue of the human and mouse Hox B3 gene, the other, PlHbox12, shows about 55% identity with paired class genes. Expression profile analysis of the two sea urchin Hbox genes suggests that they play different roles during embryogenesis. In fact, PlHbox11 transcripts are rare and are detected only in the pluteus larva and in the Aristotle's lantern and intestine of the adult. The PlHbox12 gene is, on the contrary, transiently expressed in the very early embryo already at the four cell stage; it accumulates at the 64 cell stage a…