Coordination of auxin-triggered leaf initiation by tomato LEAFLESS ($)

Capua and Eshed explored the link between auxin and leaf initiation at the shoot apical meristem, using the tomato mutant leafless (lfs), which is an ortholog of the Arabidopsis DORNRONSCHEN (DRN) and DRN-like (DRNL) genes that encode AP2-type transcription factors. The lfs mutant and the drn/drnl double mutant fail to form leaves, but instead form pin-like apices similar to those produced by polar auxin transport inhibitors. Unlike the chemically-induced pins, lfs apices do not initiate leaves in response to exogenously added auxin. The authors prospose that primordium initiation requires both auxin maxima and LFS activity. Proc. Natl. Acad. Sci. 10.1073/pnas.1617146114