Active suppression of a leaf meristem orchestrates determinate leaf growth
Abstract
Leaves are flat determinate organs derived from indeterminate shoot apical meristems. The presence of a specific leaf meristem is debated, as anatomical features typical of meristems are not present in leaves. Here we demonstrate that multiple NGATHA (NGA) and CINCINNATA-class-TCP (CIN-TCP) transcription factors act redundantly, shortly after leaf initiation, to gradually restrict the activity of a leaf meristem in Arabidopsis thaliana to marginal and basal domains, and that their absence confers persistent marginal growth to leaves, cotyledons and floral organs. The marginal restriction of the broadly acting leaf meristem following primordia initiation, is mediated by the juxtaposition of adaxial and abaxial domains and maintained by WOX homeobox transcription factors, whereas other marginal elaboration genes are dispensable for its maintenance. This genetic framework parallels the morphogenetic program of shoot apical meristems and may represent a relic of an ancestral shoot system from which seed plant leaves evolved.
Data availability
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Leaf margins of indeterminate Arabidopsis leavesPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE78693).
Article and author information
Author details
Funding
Australian Research Council (DP110100070, DP130100177, DP160100892)
- John Paul Alvarez
- Chihiro Furumizu
- John L Bowman
Israel Science Foundation (863-06)
- John Paul Alvarez
- Yuval Eshed
European Molecular Biology Organization (185-2010)
- Idan Efroni
United States - Israel Binational Agricultural Research and Development Fund (3767-05)
- John Paul Alvarez
- Yuval Eshed
- John L Bowman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Alvarez et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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