Microtubules in plant cells: structure, function and their biotechnological applications

The cytoskeleton of eukaryotic cells is a combination of different proteins that specifically interact with each other to relocate proteins and organelles at their right position in the cells. This generic function can be separated into more distinct roles, such as the assembly of the mitotic spindle for chromosome separation, the construction of specialized structures like cilia and flagella (used for generating cell or fluid movement), and the production of internal order in the cell. Classically, the cytoskeleton of plant cells is composed of actin filaments and microtubules, plus related proteins (Wasteneys and Galway, 2003), whose precise number cannot be easily calculated. Actually, the cytoskeleton is a complex mixture of proteins that interact more or less continuously with many other cellular proteins and structures. Consequently, the definition of actin-binding or microtubule-associated proteins cannot be accurate or restricted to a definite number of proteins. Actin filaments and microtubules play distinct roles in plant cells; however, such roles sometimes overlap or combine to produce a more complex function. Generally, microtubules are related to the process of cell shaping while actin filaments mainly concern with organelle movement.