Search results for "rotu"
showing 10 items of 642 documents
Response to metals treatment of Fra1, a member of the AP-1 transcription factor family, in P. lividus sea urchin embryos
2018
Abstract Lithium (Li), Nickel (Ni), and Zinc (Zn) are metals normally present in the seawater, although they can have adverse effects on the marine ecosystem at high concentrations by interfering with many biological processes. These metals are toxic for sea urchin embryos, affecting their morphology and developmental pathways. In particular, they perturb differently the correct organization of the embryonic axes (animal-vegetal, dorso-ventral): Li is a vegetalizing agent and Ni disrupts the dorso-ventral axis, while Zn has an animalizing effect. To deeply address the response of Paracentrotus lividus embryos to these metals, we studied the expression profiling of Pl-Fra transcription facto…
Non-essential role for cilia in coordinating precise alignment of lens fibres
2016
The primary cilium, a microtubule-based organelle found in most cells, is a centre for mechano-sensing fluid movement and cellular signalling, notably through the Hedgehog pathway. We recently found that each lens fibre cell has an apically situated primary cilium that is polarised to the side of the cell facing the anterior pole of the lens. The direction of polarity is similar in neighbouring cells so that in the global view, lens fibres exhibit planar cell polarity (PCP) along the equatorial-anterior polar axis. Ciliogenesis has been associated with the establishment of PCP, although the exact relationship between PCP and the role of cilia is still controversial. To test the hypothesis t…
An Intronic cis-Regulatory Element Is Crucial for the Alpha Tubulin Pl-Tuba1a Gene Activation in the Ciliary Band and Animal Pole Neurogenic Domains …
2017
In sea urchin development, structures derived from neurogenic territory control the swimming and feeding responses of the pluteus as well as the process of metamorphosis. We have previously isolated an alpha tubulin family member of Paracentrotus lividus (Pl-Tuba1a, formerly known as Pl-Talpha2) that is specifically expressed in the ciliary band and animal pole neurogenic domains of the sea urchin embryo. In order to identify cis-regulatory elements controlling its spatio-temporal expression, we conducted gene transfer experiments, transgene deletions and site specific mutagenesis. Thus, a genomic region of about 2.6 Kb of Pl-Tuba1a, containing four Interspecifically Conserved Regions (ICRs…
Diversification of spatiotemporal expression and copy number variation of the echinoid hbox12/pmar1/micro1 multigene family
2017
Changes occurring during evolution in the cis-regulatory landscapes of individual members of multigene families might impart diversification in their spatiotemporal expression and function. The archetypal member of the echinoid hbox12/pmar1/micro1 family is hbox12-a, a homeobox-containing gene expressed exclusively by dorsal blastomeres, where it governs the dorsal/ventral gene regulatory network during embryogenesis of the sea urchin Paracentrotus lividus. Here we describe the inventory of the hbox12/pmar1/micro1 genes in P. lividus, highlighting that gene copy number variation occurs across individual sea urchins of the same species. We show that the various hbox12/pmar1/micro1 genes grou…
Visualizing the spatiotemporal map of Rac activation in bovine aortic endothelial cells under laminar and disturbed flows.
2017
Disturbed flow can eliminate the alignment of endothelial cells in the direction of laminar flow, and significantly impacts on atherosclerosis in collateral arteries near the bifurcation and high curvature regions. While shear stress induced Rac polarity has been shown to play crucial roles in cell polarity and migration, little is known about the spatiotemporal map of Rac under disturbed flow, and the mechanism of flow-induced cell polarity still needs to be elucidated. In this paper, disturbed flow or laminar flow with 15 dyn/cm2 of average shear stress was applied on bovine aortic endothelial cells (BAECs) for 30 minutes. A genetically-encoded PAK-PBD-GFP reporter was transfected into BA…
Effects of exposure to gadolinium on the development of geographically and phylogenetically distant sea urchins species.
2016
Gadolinium (Gd), a metal of the lanthanide series used as contrast agent for magnetic resonance imaging, is released into the aquatic environment. We investigated the effects of Gd on the development of four sea urchin species: two from Europe, Paracentrotus lividus and Arbacia lixula, and two from Australia, Heliocidaris tuberculata and Centrostephanus rodgersii. Exposure to Gd from fertilization resulted in inhibition or alteration of skeleton growth in the plutei. The similar morphological response to Gd in the four species indicates a similar mechanism underlying abnormal skeletogenesis. Sensitivity to Gd greatly varied, with the EC50 ranging from 56 nM to 132 μM across the four species…
Sensory neuropathy in progressive motor neuronopathy(pmn)mice is associated with defects in microtubule polymerization and axonal transport
2016
Motor neuron diseases such as amyotrophic lateral sclerosis (ALS) are now recognized as multi-system disorders also involving various non-motor neuronal cell types. The precise extent and mechanistic basis of non-motor neuron damage in human ALS and ALS animal models remain however unclear. To address this, we here studied progressive motor neuronopathy (pmn) mice carrying a missense loss-of-function mutation in tubulin binding cofactor E (TBCE). These mice manifest a particularly aggressive form of motor axon dying back and display a microtubule loss, similar to that induced by human ALS-linked TUBA4A mutations. Using whole nerve confocal imaging of pmn × thy1.2-YFP16 fluorescent reporter …
Hepatitis B Virus Subverts the Autophagy Elongation Complex Atg5-12/16L1 and Does Not Require Atg8/LC3 Lipidation for Viral Maturation
2018
ABSTRACT Previous studies indicated that hepatitis B virus (HBV) stimulates autophagy to favor its production. To understand how HBV co-opts autophagy as a proviral machinery, we studied the roles of key autophagy proteins in HBV-replicating liver cell cultures. RNA interference-mediated silencing of Atg5, Atg12, and Atg16L1, which promote autophagophore expansion and LC3 membrane conjugation, interfered with viral core/nucleocapsid (NC) formation/stability and strongly diminished virus yields. Concomitantly, the core/NC membrane association and their sorting to envelope-positive compartments were perturbed. A close inspection of the HBV/autophagy cross talk revealed that the virus depended…
N-(2-methyl-indol-1H-5-yl)-1-naphthalenesulfonamide : a novel reversible antimitotic agent inhibiting cancer cell motility
2016
Este es el post-print que se ha publicado de forma definitiva en: https://www.sciencedirect.com/science/article/abs/pii/S0006295216301423 A series of compounds containing the sulfonamide scaffold were synthesized and screened for their in vitro anticancer activity against a representative panel of human cancer cell lines, leading to the identification of N-(2-methyl-1H-indol-5-yl)-1-naphthalenesulfonamide (8e) as a compound showing a remarkable activity across the panel, with IC50 values in the nanomolar-to-low micromolar range. Cell cycle distribution analysis revealed that 8e promoted a severe G2/M arrest, which was followed by cellular senescence as indicated by the detection of senescen…
Stress and immune response to bacterial LPS in the sea urchin Paracentrotus lividus (Lamarck, 1816).
2018
The immune system of the sea urchin species Paracentrotus lividus is highly complex and, as yet, poorly understood. P. lividus coelomocytes mediate immune response through phagocytosis and encapsulation of non-self particles, in addition to the production of antimicrobial molecules. Despite this understanding, details of exactly how these processes occur and the mechanisms which drive them are still in need of clarification. In this study, we show how the bacterial lipopolysaccharides (LPS) is able to induce a stress response which increases the levels of the heat shock proteins HSP70 and HSP90 only a few hours after treatment. This study also shows that LPS treatment increases the expressi…