Magalie Uyttewaal - Regulation of Plant Cell Growth and Division by new Family of Microtubule Associated Proteins

Abstract:The presence of reproducible developmental patterns and shapes in plants underlies mechanisms that ensure the robustness and coordination of cellular processes such as cell division orientation and cell growth. When a plant cell divides, a new wall is built that connects existing ones and separates daughter cytoplasms. This wall firmly binds every plant cell to its neighbors and prevents any migration. As a consequence, the topology of plant tissues mostly results from the orientation of mitoses and cell growth. Every aspects of cell growth and division involve the microtubule cytoskeleton with specialized microtubule arrays that accompany each stage of plant cell development.We have identified a major organizer of cortical microtubule arrays, the TTP complex (which contains TON1, TRM and PP2A proteins), and were able to uncouple its role in interphase from its role in mitosis by isolating specific G2/M and interphasic isoforms. The contributions of these specialized isoforms to the robustness of cell growth, cell division and plant development will be presented.