Vascular development: tracing signals along veins.

The plant hormone auxin has been implicated in vascular development, but the molecular details of patterned vascular differentiation have remained elusive. Research in the past year has identified new genes that control vascular patterning, and auxin transport and perception. New experimental strategies have been employed to study vascular development. Together, these findings have generated a conceptual framework and experimental tools for the exploration of vascular-tissue patterning at the molecular level.