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A molecular framework for plant regeneration.

Jian Xu·Hugo Hofhuis·Renze Heidstra·Michael Sauer·Jirí Friml·Ben Scheres
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Abstract

Plants and some animals have a profound capacity to regenerate organs from adult tissues. Molecular mechanisms for regeneration have, however, been largely unexplored. Here we investigate a local regeneration response in Arabidopsis roots. Laser-induced wounding disrupts the flow of auxin-a cell-fate-instructive plant hormone-in root tips, and we demonstrate that resulting cell-fate changes require the PLETHORA, SHORTROOT, and SCARECROW transcription factors. These transcription factors regulate the expression and polar position of PIN auxin efflux-facilitating membrane proteins to reconstitute auxin transport in renewed root tips. Thus, a regeneration mechanism using embryonic root stem-cell patterning factors first responds to and subsequently stabilizes a new hormone distribution.

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ArabidopsisArabidopsis ProteinsBiological TransportCell NucleusGenes, PlantIndoleacetic AcidsMembrane Transport ProteinsModels, BiologicalPlant Growth RegulatorsPlant RootsRecombinant Fusion ProteinsRegenerationStem CellsTranscription FactorsJournal ArticleResearch Support, Non-U.S. Gov't

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Jian Xu, Hugo Hofhuis, Renze Heidstra, Michael Sauer, Jirí Friml, Ben Scheres. 2006-01-20. A molecular framework for plant regeneration.. https://doi.org/10.1126/science.1121790

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