Controlling cellular development in a single cell system of Nicotiana.

Cells regenerated from freshly isolated leaf mesophyll protoplasts can be induced to develop along very different pathways. Depending on the hormone content and the mechanical characteristics of the environment, cells choose between division and expansion. In the former case they form microcolonies of isodiametric cells, while in the latter they exhibit a typical tubular growth or increase their volume considerably by bulging and budding. A culture method was developed which allows a careful control of the experimental environment and non-destructive high resolution monitoring of development of individual cells.