Cellular differentiation in the leaf.

The past year has seen significant advances in our understanding of the mechanisms that regulate cellular differentiation in the leaf. It has been suggested that a common developmental pathway involving MYB-like transcription factors is responsible for distinguishing between cellular identities in the epidermis and that nuclear-cytoplasmic partitioning of the GLABRA2 homeodomain protein plays a role in determining trichome cell fate. With respect to the differentiation of subepidermal cell types, molecular links have been made between auxin physiology and vascular development, and between plastid function and photosynthetic cell type development.