Search results for " sea urchin."

Vanadium perturbs the fertilization outcome and the metalloproteinase activity in sea urchin embryos

2021

Metal toxicology represents a current major topic due to the disper- sion of these elements in the environment. Metals are released from both natural sources and industrial activities. Some of them have also a clinical interest due to their application as metallodrugs (i.e., Pt, Cu, Au, Ru, and Y) or in medical diagnosis (Gd).1,2 Recently, V derivatives are considered as potential therapeutic factors in some diseases (e.g., obesity, diabetes, cancer, neurodegenerative and heart disorders). As a consequence, pharmaceutical residues could repre- sent emerging pollutants of aquatic environments, as wastewater treatment plants do not sufficiently remove these compounds3. Embryonic models repres…

The Sea Urchin sns Insulator Blocks CMV Enhancer following Integration in Human Cells

2001

Insulators are a new class of genetic elements that attenuate enhancer function directionally. Previously, we characterized in sea urchin a 265-bp-long insulator, termed sns. To test insulator activity following stable integration in human cells, we placed sns between the CMV enhancer and a tk promoter up-stream of a GFP transgene of plasmid or retroviral vectors. In contrast to controls, cells transfected or transduced with insulated constructs displayed a barely detectable fluorescence. Southern blot and PCR ruled out vector rearrangement following integration into host DNA; RNase protection confirmed the enhancer blocking activity. Finally, we demonstrate that two cis-acting sequences, p…

Bioactive molecules from soil and marine bacteria: new potential applications

2015

CELLULAR AND MOLECULAR MECHANISMS ACTIVATED IN SEA URCHIN EMBRYOS EXPOSED TO GADOLINIUM, EMERGING ENVIRONMENTAL CONTAMINANT

On hidden heterogeneity in directional asymmetry – can systematic bias be avoided?

2006

8 pages; International audience; Directional asymmetry (DA) biases the analysis of fluctuating asymmetry (FA) mainly because among-individual differences in the predisposition for DA are difficult to detect. However, we argue that systematic bias mainly results from predictable associations between signed right-left asymmetry and other factors, i.e. from systematic variation in DA. We here demonstrate methods to test and correct for this, by analysing bilateral asymmetry in size and shape of an irregular sea urchin. Notably, in this model system, DA depended significantly on body length and geographic origin, although mean signed asymmetry (mean DA) was not significant in the sample as a wh…

Effect of environmental stress on sea urchin embryos and larvae: from developmental to molecular biology analyses

2010

Identification of GABA receptor genes and evidence of GABA signaling during embryogenesis of the sea urchin

2012

Gamma-aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the mammalian central nervous system and acts via ionotropic (GABAA-Rs) and metabotropic (GABAB-Rs) receptors. GABAA-Rs are Cl- selective hetero-pentameric channels assembled by combinations of 19 distinct gene products. Instead, GABAB-Rs are bi-subunit G-protein coupled receptors linked to K+ or Ca2+ channels. Dysfunctions of GABA-signaling (GS) cause psychotic disorders and correlate with epigenetic alterations, such as over-expression of DNA methyl transferase-1 which in turn imposes iper-methylation of GABA-regulated genes. The sea urchin embryo, which presents a rudimentary nervous system, offers a big oppor…

Identification of a putative GAGA factor in P. lividus embryos

2015

Hbox12: an old gene with a new function.

2013

Development of Phosphatized Calcium Carbonate Biominerals as Bioactive Bone Graft Substitute Materials, Part I: Incorporation of Magnesium and Stront…

2018

Synthetic materials based on calcium phosphate (CaP) are frequently used as bone graft substitutes when natural bone grafts are not available or not suitable. Chemical similarity to bone guarantees the biocompatibility of synthetic CaP materials, whereas macroporosity enables their integration into the natural bone tissue. To restore optimum mechanical performance after the grafting procedure, gradual resorption of CaP implants and simultaneous replacement by natural bone is desirable. Mg and Sr ions released from implants support osteointegration by stimulating bone formation. Furthermore, Sr ions counteract osteoporotic bone loss and reduce the probability of related fractures. The presen…