Molecular and cellular aspects of auxin-transport-mediated development

The plant hormone auxin is frequently observed to be asymmetrically distributed across adjacent cells during crucial stages of growth and development. These auxin gradients depend on polar transport and regulate a wide variety of processes, including embryogenesis, organogenesis, vascular tissue differentiation, root meristem maintenance and tropic growth. Auxin can mediate such a perplexing array of developmental processes by acting as a general trigger for the change in developmental program in cells where it accumulates and by providing vectorial information to the tissues by its polar intercellular flow. In recent years, a wealth of molecular data on the mechanism of auxin transport and its regulation has been generated, providing significant insights into the action of this versatile coordinative signal.