ARS | Publication request: How a leaf gets its shape

Submitted to: Current Opinion in Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 1, 2011
Publication Date: June 1, 2011
Citation: Moon, J., Hake, S.C. 2011. How a leaf gets its shape. Current Opinion in Plant Biology. 14:24-30.

Interpretive Summary: Leaves are formed from a group of initial cells within the meristem. One of the earliest markers of leaf initiation is the down-regulation of KNOX genes in initial cells. Polar auxin activity, MYB and LOB domain transcription factors function to keep KNOX out of the initiating leaf. If KNOX genes are expressed in initial cells, leaves fail to form. As the leaf grows away from the meristem, its shape is determined by growth in three axes, proximal–distal, abaxial–adaxial and medial–lateral. KNOX proteins play a role in the proximal–distal axis. Although genetic networks are conserved between monocots and dicots, the outcome in leaf shape often differs.

Technical Abstract: Leaf development is contrasted between dicots and monocots with a focus on transcription factors that function in morphology. Recent information on small RNA signaling is described.