Search results for "sea urchin."

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…

Synthesis, structural investigations on organotin(IV) chlorin-e6 complexes, their effect on sea urchin embryonic development and induced apoptosis

2004

Four new organotin(IV) chlorin derivatives, [chlorin=chlorin-e(6)=21H,23H-porphine-2-propanoic acid, 18-carboxy-20-(carboxymethyl)-8-ethenyl-13-ethyl-2,3-di-hydro-3,7,12,17-tetramethyl-(2S-trans)-], with formula (R(2)Sn)(3)(chlorin)(2).2H(2)O (R=Me, n-Bu) and (R(3)Sn)(3)chlorin.2H(2)O (R=Me, Ph) have been synthesized. The solid state and solution phase structures have been investigated by FT-IR, (119)Sn Mössbauer, (1)H and (13)C NMR spectroscopy. In the solid state, (R(2)Sn)(3)(chlorin)(2).2H(2)O complexes contain six coordinated Sn(IV), in a skew trapezoidal environment by forming trans-R(2)SnO(4) polymeric units. As far as (R(3)Sn)(3)chlorin.2H(2)O complexes are concerned, Sn(IV) is five …

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…

The Ambulacraria-specific COMPASS-like protein contributes to sns5 chromatin insulator function in the sea urchin embryo

2013

Cellular, biochemical and molecular effects of cadmium on marine invertebrates: focus on Paracentrotus lividus sea urchin development

2009

Cadmium is a heavy metal that is toxic for living organisms even at low concentrations. The presence in the environment of this metal has grown because of its large employment in some industrial and agricultural activities. Although heavy metals are terrestrially produced, they flow into the sea through effluents and sewage or are directly discharged from industries placed on the seawater front. In addition to its release into costal waters, cadmium fallout, following atmospheric events, contributes to the pollution of marine ecosystems. It should be considered that cadmium concentrations determined in the field vary widely according to different seawater latitudes and depths and can be str…

Relationship between autophagy and apoptosis in Paracentrotus lividus embryos cadmium exposed

2011

Cadmium is a strong toxicant for living organism since it does not have biological roles and can cause several cellular damages comprising genotoxicity, oxidative stress, and other biochemical dysfunctions. Marine invertebrate embryos represent a suitable model system where to investigate the effects of many stressors on development and cell viability. Here we investigated the toxic effect of cadmium on sea urchin Paracentrotus lividus embryos focusing our attention on metal-inducead autophagy and the possible temporal and functional relationship with apoptosis. Using several techniques to detect autophagy (neutral red, acridine orange and LC3-detection) we demonstrated that Cd-exposed P. l…

DNA Damage and Developmental Defects After Exposure to UV and Heavy Metals in Sea Urchin Cells and Embryos Compared to Other Invertebrates

2005

The depletion of the stratospheric ozone layer and the resulting increase in hazardous ultraviolet-B (UV-B) radiation reaching the Earth are of major concern not only for terrestrial but also for aquatic organisms. UV-B is able to penetrate clear water to ecologically significant depths. This chapter deals with the effects of UV radiation on DNA integrity in marine benthic organisms, in particular sea urchins in comparison to other marine invertebrates (sponges and corals). These animals cannot escape the damaging effects of UV-B radiation and may be additionally exposed to pollution from natural or anthropogenic sources. Besides eggs and larvae that lack a protective epidermal layer and ar…

Environmentally relevant cadmium concentrations affect development and induce apoptosis of Paracentrotus lividus larvae cultured in vitro. Epub ahead…

2008

Sea urchin embryos and larvae represent suitable model systems on where to investigate the effects of heavy metals on development and cell viability. Here, we tested the toxic effects of low (10(-12 )M), medium (10(-9 )M), and high (10(-6 )M) cadmium chloride concentrations, mimicking unpolluted, moderately and highly polluted seawaters, respectively, on Paracentrotus lividus sea urchins offspring. Larvae were continuously treated from fertilization and inspected at time intervals comprised between 10 and 30 days of development. Delays and/or morphological abnormalities were firstly evident in larvae treated for 15 days with high cadmium (10(-6 )M) and for 25 days with medium cadmium (10(-9…

Characterization of bep1 and bep4 antigens involved in cell interactions during Paracentrotus lividus development

1992

Abstract We have identified and partially characterised two antigens, extracted with 3% butanol, from Paracentrotus lividus embryos dissociated at the blastula stage, and encoded by the cDNA clones previously described as bep1 and bep4 (bep-butanol extracted proteins). The cDNA fragments containing the specific central portions of bep1 and bep4 were expressed as MS2 polymerase fusion proteins in Escherichia coli. These two fusion proteins, called 1C1 (bep1) and 4A1 (bep4), were injected subcutaneously into rabbits and the corresponding polyclonal antibodies generated. Western blot analysis of proteins, extracted with 3% butanol, from sea urchin embryos at the blastula stage (b.e.p.), establ…

The Compass-like Locus, Exclusive to the Ambulacrarians, Encodes a Chromatin Insulator Binding Protein in the Sea Urchin Embryo

2013

Chromatin insulators are eukaryotic genome elements that upon binding of specific proteins display barrier and/or enhancer-blocking activity. Although several insulators have been described throughout various metazoans, much less is known about proteins that mediate their functions. This article deals with the identification and functional characterization in Paracentrotus lividus of COMPASS-like (CMPl), a novel echinoderm insulator binding protein. Phylogenetic analysis shows that the CMPl factor, encoded by the alternative spliced Cmp/Cmpl transcript, is the founder of a novel ambulacrarian-specific family of Homeodomain proteins containing the Compass domain. Specific association of CMPl…