Related Experiment Video
Updated: Jul 15, 2026

Long-term, High-resolution Confocal Time Lapse Imaging of Arabidopsis Cotyledon Epidermis during Germination
Published on: December 31, 2012
An evolutionarily conserved mechanism delimiting SHR movement defines a single layer of endodermis in plants
Hongchang Cui1, Mitchell P Levesque, Teva Vernoux
1Department of Biology and Institute for Genome Sciences and Policy, Duke University, Durham, NC 27708, USA.
Abstract:
Intercellular protein movement plays a critical role in animal and plant development. SHORTROOT (SHR) is a moving transcription factor essential for endodermis specification in the Arabidopsis root. Unlike diffusible animal morphogens, which form a gradient across multiple cell layers, SHR movement is limited to essentially one cell layer. However, the molecular mechanism is unknown. We show that SCARECROW (SCR) blocks SHR movement by sequestering it into the nucleus through protein-protein interaction and a safeguard mechanism that relies on a SHR/SCR-dependent positive feedback loop for SCR transcription. Our studies with SHR and SCR homologs from rice suggest that this mechanism is evolutionarily conserved, providing a plausible explanation why nearly all plants have a single layer of endodermis.
Related Concept Videos
The Apoplast and Symplast
Plasmodesmata
Plasmodesmata
Intercellular junctions are a feature of fungal, plant, and animal cells. However, different types of junctions are found in different kinds of cells. Intercellular junctions found in animal cells include tight junctions, gap junctions, and...
Adaptations that Reduce Water Loss
Morphogenesis
Water and Mineral Acquisition

