Asymmetric cell division--how flowering plant cells get their unique identity.

Abstract

A central question in biology is how cell fate is specified during development of a multicellular organism. Flowering plants use two major pathways of asymmetric cell divisions in a spatio-temporal manner to achieve required cellular differentiation. In the 'one mother--two different daughters' pathway, a mother cell mitotically divides to produce two daughter cells of different size and fate. By contrast, the 'coenocyte-cellularization' pathway involves formation of a coenocyte, nuclear migration to specific locations of the coenocyte and cellularization of these nuclei by unique wall forming processes. Given that cell fate determinants play a key role in establishing cell identity, their allocation to daughter cells in the two pathways needs to be understood in terms of the unique cell cycle regulatory mechanisms involved. Most of the information available on cell fate determination in flowering plants is in the form of genes identified from mutant analysis. Novel techniques of interrogating individual plant cells in vivo are necessary to advance the extant knowledge from genetics to functional genomics data bases.