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As a valuable source of energy, plant cell walls are extensively used as raw material for food and more recently biofuel industries. Although the structure of cell wall polysaccharides is nowadays relatively well-documented, little is known about their biosynthesis. Recently, at INRA-Nantes, France, Suliman et al. (2013) have isolated Golgi-enriched fractions from wheat endosperm and detected in these fractions the presence of 64 putative glycosyltransferases (GTs). The research proposed here aims to determine in wheat the function of one of these GTs that belongs to the Cellulose Synthase-Like D family. To date, the exact activity of the CSLD proteins remains unclear as, in Arabidopsis thaliana, divergent studies have reported that the CSLD proteins act in the (1?4)-?-D-glucan and the mannan (Verhertbruggen et al. (2011)) synthesis. In wheat endosperm, the host group has detected the presence of a single CSLD protein, CSLD2. In addition to gaining knowledge on wheat cell wall biosynthesis, defining the role of CSLD2 in wheat endosperm might clarify the activity present in the CSLD family. Collaborators from Rothamsted Research have produced RNA interference (RNAi) transformants in wheat, targeting CSLD2. The candidate, Yves Verhertbruggen, will carry out the characterization of cell wall polysaccharides in wild type and in CSLD2 RNAi wheat grains using advanced techniques developed at INRA Nantes such as enzymatic fingerprinting, FT-IR microspectroscopy, MALDI-MS imagery and immunocytochemistry. This project will indicate which polymer(s) is or are affected by silencing the CSLD2 gene and will give information on the physiological function of CSLD2. Based on the results obtained from the characterization of the RNAi transformant, biochemical assays using tobacco cells and Pichia pastoris both expressing the wheat CSLD2 will be performed to test the possible glycosyltransferase activity of CSLD2. Moreover, during this work, a particular attention will be brought to the physico-chemical properties of mannan, the potential product resulting from the CSLD2 activity and whose structure still needs to be determined. References:  Suliman, M., Chateigner-Boutin, A.L., Francin-Allami, M., Partier, A., Bouchet, B., Salse, J., Pont, C., Marion, J., Rogniaux, H., Tessier, D., Guillon, F., Larré, C. (2013) Identification of glycosyltransferases involved in cell wall synthesis of wheat endosperm. Journal of Proteomics 78, 508-521.  Park, S., Szumlanski, A.L., Gu, F., Guo, F., Nielsen, E. (2011) A role for CSLD3 during cell wall synthesis in apical plasma membranes of tip-growing root hair cells. Nature Cell Biology 13, 973-980.  Verhertbruggen, Y., Yin, L., Oikawa, A., Manisseri, C., Knierim, B., Prak, L., Jensen, J.K., Knox, J.P., Auer, M., Willats, W.G.T., Scheller, H.V. (2011) The cooperative activities of CSLD2, CSLD3, and CSLD5 are required for normal arabidopsis development. Molecular Plant 4, 1024-1037.
Plant cell walls are my field of expertise. I obtained my PhD in biological sciences at the University of Leeds, UK, in 2009. I conducted a 4 years post-doctoral research at the Joint BioEnergy Institute (LBNL/UC Berkeley, USA). The laboratory focuses its research on biofuel production and, there, I have contributed to a better understanding of plant cell walls and their biosynthesis As an AgreenSkills fellow, my work aimed to understanding how mannan, a cell wall polysaccharide, impact the development of wheat endosperm. I studied the biosynthesis, the structure and the biological function of this polymer. I have obtained a Marie Curie Individual Fellowship to pursue this project in the same lab. If you wish to know more about my research, I invite you to have a look at the following link: http://www.researchgate. net/profile/Yves_Verhertbruggen
Verhertbruggen Y, Walker JL, Guillon F and Scheller HV., 2017. A Comparative Study of Sample Preparation for Staining and Immunodetection of Plant Cell Walls by Light Microscopy. Front. Plant Sci. 8:1505. Doi: 10.3389/ fpls.2017.01505.
Amsbury, S., Hunt, L., Elhaddad, N., Baillie, A., Lundgren, M., Verhertbruggen, Y., Scheller, HV., Knox, JP., Fleming, AJ., Gray, JE, 2016. Stomatal Function Requires Pectin De-methyl-esterification of the Guard Cell Wall. Current Biology, 26 (21), 2899-2906.
Chateigner-Boutin, AL., Ordaz-Ortiz, JJ., Alvarado, C., Bouchet, B., Durand, S., Verhertbruggen, Y., Barriere, Y., Saulnier, L, 2016. Developing Pericarp of Maize: A Model to Study Arabinoxylan Synthesis and Feruloylation. Frontiers In Plant Science, 7. Doi: 10.3389/ fpls.2016.01476.
Verhertbruggen Y, Marcus SE, Chen J, Knox JP. 2013. Cell wall pectic arabinans influence the mechanical properties of Arabidopsis thaliana inflorescence stems and their response to mechanical stress. Plant Cell and Physiology, 54, 1278-1288.
Verhertbruggen Y, Yin L, Oikawa A, Manisseri C, Knierim B, Prak L, Jensen JK, Knox JP, Auer M, Willats WGT, Scheller HV. 2011. The cooperative activities of CSLD2, CSLD3, and CSLD5 are required for normal arabidopsis development. Molecular Plant, 4, 1024- 1037.
Verhertbruggen Y, Marcus SE, Haeger A, Verhoef R, Schols HA, McCleary BV, McKee L, Gilbert HJ, Knox JP. 2009. Developmental complexity of arabinan polysaccharides and their processing in plant cell walls. Plant Journal, 59, 413-425.
Marie Curie Fellowship WALLNET RTN FP6
Marie Curie Fellowship AgreenSkills COFUND FP7
Marie Curie Individual Fellowship H2020
2012 Director’s Award for Exceptional Scientific Achievement (Lawrence Berkeley National Laboratory, CA, USA)
Image cover of plant journals and book (i.e.:Plant Cell and Physiology (Vol. 54, issue 8, Aug. 2013); Analytical Chemistry (Vol. 82, number 22, Nov. 2010); Proteomic Applications in Biology, Heazlewood JL and Petzold CL (eds.) Intech 2012; …)