Armbrust Lab

Last update June 2009

Postdoctoral Research Associate, ribalet at u.washington.edu

Research interests

My research mainly focuses on adaptation of diatoms to coastal and open ocean environments. I am interested in the molecular mechanisms of stress response in marine diatoms. Diatoms produce a wide range of molecules that allow them to adapt to various environmental conditions. I am particulalry interested in oxylipins (molecules produced from the oxidation of fatty acids), which are expected to play an important role in stress-related responses in diatoms. I am using a combination of physiological, molecular and ecological approaches to elucidate the function of these molecules in the diatom Pseudo-nitszchia multiseries.

Understanding how diatoms respond to different environments is limited, but not exclusively, by traditional discrete sampling approaches that typically average across large temporal and spatial scales. I am currently implementing the coordination of a new generation of flow cytometer (Seaflow) developed by Jarred Swalwell at the University of Washington, that perfoms underway measurements of abundance and structure of phytoplankton assemblage. This instrument offers continuous quantification of multidimensional characteritics (cell size, pigment content) for thousands of cells per second, including some diatoms, and allows me to address fine temporal and spatial distributions of diatoms in complex environmental gradients, such as at the transition zone between coastal and open-ocean waters. The continuous amount of data generated every day by SeaFlow requires the development of new analytical tools. Together with Dave Schruth, we are adapting a multivariate gating method that use advanced model-based clustering approach to automate the identification of phytoplankton populations and reduce the significant subjectivity and human time coast associated with it. 

Education

• 2007 Ph.D in Biological Sciences – Open University of London, UK, hosted by the Stazione Zoologica Anton Dohrn, Naples, IT
• 2003 M.Sc in Biological Oceanology and Marine Environment – University Pierre & Marie Curie, Paris, FR
• 2001 B.Sc in Population Biology and Ecosystems – University Pierre & Marie Curie, Paris, FR
• 1997-1999 Post-secondary preparatory classes for the entrance at the French Grandes Ecoles – Ecole Superieure d’Agriculture d’Angers, FR

Publications

• Ribalet, F., Marchetti, A., Durkin, C.A., Hubbard, K.A., Morales, R., Swalwell, J., Tortell, P.D., van den Engh, G., and Armbrust, V.E. Cryptic blooms of offshore phytoplankton in the transition zone between oceanic and coastal waters. In preparation
• Ribalet, F., Vidoudez, C., Bastianini, M., Romano, G., Wichard, T., Pohnert, G., Ianora, A., Miralto, A., and Casotti, R. Phytoplankton lysis during a recurrent bloom of the diatom Skeletonema marinoi in the Northen Adriatic Sea. In preparation
• Ribalet, F., Vidoudez, C., Cassin, D., Pohnert, G., Ianora, A., Miralto, A., and Casotti, R. 2009. High plasticity in the production of diatom-polyunsaturated aldehydes under nutrient limitation: Physiological and ecological implications. Protist,160:444-451 pdf
• Marchetti*, A., Parker*, M.S., Moccia, L.P., Lin, E.O., Arrieta, A.L., Ribalet, F., Murphy, M.E.P., Maldonado, M.T., and Armbrust, V.E. 2008. Iron storage by ferritin in bloom-forming marine pennate diatoms. Nature, 457:467-470 pdf
• Ribalet, F., Intertaglia, L., Lebaron, P., and Casotti, R. 2008. Differential effect of three polyunsaturated aldehydes on marine bacterial isolates. Aquatic Toxicology 86: 249-255 pdf
• Ribalet, F. 2007. The role of polyunsaturated aldehyde production in the physiology and ecology of diatoms. Thesis, Open University of London, 270 p.
• Ribalet, F., Berges, J.A., Ianora, A., and Casotti, R. 2007. Growth inhibition of cultured marine phytoplankton by toxic algal-derived polyunsaturated aldehydes. Aquatic Toxicology 85:219-227 pdf
• Ribalet, F., Wichard, T., Pohnert, G., Ianora, A., Miralto, A., and Casotti, R. 2007. Age and nutrient limitations enhance aldehyde production in marine diatoms. Phytochemistry 68: 2059-2067 pdf
• Vardi*, A., Formiggini*, F., Casotti, R., de Martino, A., Ribalet, F., Miralto, A., and Bowler, C. 2006. A stress surveillance system based on calcium and nitric oxide in marine diatoms. PLoS Biology 4: 411-419A pdf

Patent

• Swalwell, J., Ribalet F. Optimal Gating Method for Position Sensitive Detection in Flow Cytometry. Patent pending