Abstract
This chapter introduces plant cell strains and describes their main characteristics which render them unique experimental models to study plant morphogenesis. Although composed only of few cells, these systems are characterised by strict natural polarity of cell growth and division and high spontaneous friability of the daughter cell files.
Both features are most clearly exhibited in two tobacco cell lines, Virginia Bright Italia (VBI-0) and Bright Yellow (BY-2). Owing to their ability to grow in vitro resembling animal single cell layer systems, they offer the possibility to accompany molecular or biochemical analyses of the material by a precise but nondestructive in vivo cytological observation of the cell population.
Here we summarise the use of these two lines in various plant phenotyping studies including investigations of morphoregulatory signals like phytohormones or stress factors as well as organisation of cytoskeleton, endomembranes and cell wall. Although so far not frequently utilised in practical applications, some transgenic BY-2 strains show high potential for molecular farming.
Last but not the least, the mechanisms responsible for the spontaneous or targeted selection of similar plant cell strains from genetically more attractive plant species are discussed.