Intercellular signalling in the transition from stem cells to organogenesis in meristems

Meristems continuously produce new cells to sustain plant growth. Stem cells are maintained in the centre of the meristern and provide the precursor cells for the initiation of new organs and tissues in the periphery. The structure of the meristern is maintained while cells are constantly displaced by new divisions. Recent advances have been made in understanding the intercellular signals that maintain meristern structure by adjusting gene expression according to cell position. In addition to refinements in our understanding of how the position and size of the stem-cell population is regulated, there have been advances in understanding how the location of new organ primordia is controlled and how the meristern influences organ polarity.