Related Experiment Video
Updated: May 22, 2026

Lateral Root Inducible System in Arabidopsis and Maize
Published on: January 14, 2016
Phloem-associated auxin response maxima determine radial positioning of lateral roots in maize
Leentje Jansen1, Ianto Roberts, Riet De Rycke
1Department of Plant Systems Biology, Integrative Plant Biology Division, VIB, Technologiepark 927, 9052 Ghent, Belgium.
Abstract:
In Arabidopsis thaliana, lateral-root-forming competence of pericycle cells is associated with their position at the xylem poles and depends on the establishment of protoxylem-localized auxin response maxima. In maize, our histological analyses revealed an interruption of the pericycle at the xylem poles, and confirmed the earlier reported proto-phloem-specific lateral root initiation. Phloem-pole pericycle cells were larger and had thinner cell walls compared with the other pericycle cells, highlighting the heterogeneous character of the maize root pericycle. A maize DR5::RFP marker line demonstrated the presence of auxin response maxima in differentiating xylem cells at the root tip and in cells surrounding the proto-phloem vessels. Chemical inhibition of auxin transport indicated that the establishment of the phloem-localized auxin response maxima is crucial for lateral root formation in maize, because in their absence, random divisions of pericycle and endodermis cells occurred, not resulting in organogenesis. These data hint at an evolutionarily conserved mechanism, in which the establishment of vascular auxin response maxima is required to trigger cells in the flanking outer tissue layer for lateral root initiation. It further indicates that lateral root initiation is not dependent on cellular specification or differentiation of the type of vascular tissue.
More Related Videos
06:11Improved Methods for Preparing Transverse Sections and Unrolled Whole Mounts of Maize Leaf Primordia for Fluorescence and Confocal Imaging
Published on: September 22, 2023
12:18A Strategy to Validate the Role of Callose-mediated Plasmodesmal Gating in the Tropic Response
Published on: April 17, 2016
Related Concept Videos
Responses to Gravity and Touch
Primary and Secondary Growth in Roots and Shoots
Cell Signaling in Plants
Plant Hormones
Morphogenesis
Water and Mineral Acquisition