Cytoskeletal, perspectives on root growth and morphogenesis

Growth and development of all plant cells and organs relies on a fully func tional cytoskeleton comprised principally of microtubules and microfilament s. These two polymeric macromolecules, because of their location within the cell, confer structure upon, and convey information to, the peripheral reg ions of the cytoplasm where much of cellular growth is controlled and the f ormation of cellular identity takes place. Other ancillary molecules, such as motor proteins, are also important in assisting the cytoskeleton to part icipate in this front-line work of cellular development. Roots provide not only a ready source of cells for fundamental analyses of the cytoskeleton, but the formative zone at their apices also provides a lo cale whereby experimental studies can be made of how the cytoskeleton permi ts cells to communicate between themselves and to cooperate with growth-reg ulating information supplied from the apoplasm.