Marginal differences play a central role in complex leaf development

摘要

Development involves a delicate patterning of cell division and differentiation in three dimensions. This is beautifully illustrated in leaves, where three axes are visible: proximodistal (from base to tip), mediolateral (from the midvein to the margin/edge of the blade), and adaxial–abaxial (from upper to lower surface of the blade). Years of work have identified genes that control patterning along these axes, but how their activity is organized in time and space to control leaf development is less well understood.