The barbel-like specialization of the pelvic fins in Ophidion rochei (Ophidiidae)

in Journal of Morphology (2012), 273(12), 1367-1376

Continuous synthesis of porous carbon xerogel beads. Communication présentée par D. Eskenazi

Conference (2012, June 17)

Topical application of liposomes: parameters influencing their effectiveness

Poster (2011, June 14)

Insertional mutagenesis to select mutants for modified hydrogen photoproduction in Chlamydomonas reinhardtii

Poster (2011, May 17)

The unicellular green alga Chlamydomonas reinhardtii has evolved the ability to redirect electrons from the photosynthetic chain to drive hydrogen production via chloroplast oxygen-sensitive hydrogenases ... [more ▼]

The unicellular green alga Chlamydomonas reinhardtii has evolved the ability to redirect electrons from the photosynthetic chain to drive hydrogen production via chloroplast oxygen-sensitive hydrogenases. This process occurs under anaerobic conditions and provides a biological basis for solar-driven hydrogen production. Nevertheless, the yield is a major limitation for an economic viability and fundamental knowledge is still needed in order to have a better understanding of the process. In 2000, Melis and co-worker defined a protocol allowing a sustainable hydrogen production in sulfur deprivation condition. By adjustment of an existent protocol called the Winkler test, we are trying to isolate mutants with an attenuated photosynthesis to respiration capacity ratio (P/R ratio). This kind of mutants could be able to reach anoxia needed for hydrogenases activity without the stressful impact of sulfur deprivation. An insertional mutagenesis of Chlamydomonas has been carried out with an hygromycin resistance cassette and about 2500 transformants have generated and screened by the adapted Winkler test. We have isolated several oxygen-consuming mutants and the most promising one is subject to functional, molecular and genetic characterization. To discover new genes involved in hydrogenases activity, we are also planning to screen the same insertional library for mutants with attenuated levels of hydrogen photoproduction, using sensitive chemochromic sensor films which turn in blue in presence of hydrogen. We are currently making the chemochromic sensor WO3 films by dip-coating which is on the brink of being useable. [less ▲]

Organo-mineral imprints in fossil cyanobacterial mats of an Antarctic lake

Poster (2011, April 07)

In vitro culture of the parasitic wasp Aphidius ervi: Sweet dream or Reality

Poster (2011, March 03)

Aphidius ervi is an entomophagous parasitoid and represents an effective parasitoid of several aphid species that cause great damages in agriculture. Several investigations, for its in vitro mass ... [more ▼]

Aphidius ervi is an entomophagous parasitoid and represents an effective parasitoid of several aphid species that cause great damages in agriculture. Several investigations, for its in vitro mass production, have achieved a limited success and suggest that in vitro culture of this valuable biological control agent is rather closer to a dream than reality. Our work provides a chronological study of A. ervi development, from the oviposition until hatching of the first instar larva, in the body of the pea aphid Acyrthosiphon pisum. We show that this parasitoid has some characteristics in its embryological development that are rather complex and different from most other reported insects, which can be phylogenetically very close. Some of these characteristics concern extraembryonic membranes and could be among the causes of the limited success achieved in the in vitro culture. [less ▲]

Organo-mineral imprints in fossil cyanobacterial mats of an Antarctic lake

Poster (2010, December)

Structure composition and mechanical relations to function in sea urchin spine

in Journal of Structural Biology (2010), 170

INPP5E mutations cause primary cilium signaling defects, ciliary instability and ciliopathies in human and mouse

in Nature Genetics (2009), 41

The primary cilium is an antenna-like structure that protrudes from the cell surface of quiescent/differentiated cells and participates in extracellular signal processing1–3. Here, we report that mice ... [more ▼]

The primary cilium is an antenna-like structure that protrudes from the cell surface of quiescent/differentiated cells and participates in extracellular signal processing1–3. Here, we report that mice deficient for the lipid 5-phosphatase Inpp5e develop a multiorgan disorder associated with structural defects of the primary cilium. In ciliated mouse embryonic fibroblasts, Inpp5e is concentrated in the axoneme of the primary cilium. Inpp5e inactivation did not impair ciliary assembly but altered the stability of pre-established cilia after serum addition. Blocking phosphoinositide 3-kinase (PI3K) activity or ciliary platelet-derived growth factor receptor a (PDGFRa) restored ciliary stability. In human INPP5E, we identified a mutation affecting INPP5E ciliary localization and cilium stability in a family with MORM syndrome, a condition related to Bardet-Biedl syndrome. Together, our results show that INPP5E plays an essential role in the primary cilium by controlling ciliary growth factor and PI3K signaling and stability, and highlight the consequences of INPP5E dysfunction. [less ▲]

First insights into the gut microflora associated with an echinoid from wood falls environments

in Cahiers de Biologie Marine (2009), 50