IR EFS

Catherine Strassel obtained her doctorate in 2004 at the University of Strasbourg, Strasbourg, France under the direction of François Lanza. During her thesis, she was interested in studying the role of GPIbbeta in megakaryopoiesis and haemostasis. She pursued a postdoctoral internship with François Lanza in the INSERM U949 team at EFS-Alsace in Strasbourg, France. Appointed a research scientist in the INSERM U949 team in 2007, she is currently the main collaborator of François Lanza.

Research Themes :

Blood platelets are produced from a giant bone marrow progenitor cell, the megakaryocyte. My research focuses on the understanding of platelet production mechanisms, thrombopoiesis, under physiological and pathological conditions. I am particularly interested in: (i) the mechanism of assembly of the marginal band of microtubules in the final stages of platelet release by megakaryocytes, (ii) the role of the hematopoietic niche in the differentiation of megakaryocytes.

(i) Platelets have a characteristic lenticular shape supported by a circular membrane under membrane of microtubules (MTs) called marginal band. The importance of this cytoskeleton, whose structure is unique in mammalian cells, is illustrated by the presence of abnormal platelets and a tendency to bleed in patients carrying mutations on the gene coding for tubulin beta1. This circular assembly of MTs occurs late during megakaryopoiesis, at the stage where the proplaquettes are formed, which are cytoplasmic extensions terminated by platelet buttons. The goal here is to understand the mechanisms that govern this particular assemblage. A transdisciplinary approach is undertaken to systematically study, in platelets and during their biogenesis, the repertoire of tubulin alpha and beta isotypes, their post-translational modifications and the proteins associated with MTs. It will combine biophysical and structural, biochemical, cell biology and mouse models.

Collaboration with C. Schaeffer (LSMBO, Strasbourg) and C.Janke (Institut Curie, Paris)

(ii) Approximately 2,000 platelets are released by each megakaryocyte following an elaborate process. To date, the production yields of platelets in culture are very far from reaching this level because of an inability to reproduce all the conditions encountered in the bone marrow. Our goal in the laboratory is to identify the essential elements leading to the release of platelets and to develop culture protocols that reproduce these conditions. My studies focus on two areas: i) the identification of the most appropriate haematopoietic progenitors to engage in the megakaryocyte pathway and ii) the study of the role of the microenvironment and in particular stromal cells. These studies will serve as a basis for improving the production of platelets in culture.

Work done with Nathalie Brouard, Collaboration with Karin Tarte (EFS, Rennes)

Publications

Nothing found.