Root Type-Specific Establishment of Postembryonic Stem Cell Niches During Maize Lateral Root Formation

Lateral roots are established from pericycle stem cell niches of other roots. In maize, phloem pole pericycle cells give rise to lateral roots. Our overreaching hypothesis is that the establishment of lateral root stem cell niches involves conserved and distinct players in the different root types of maize. In this project, we will (i) study the cellular organization of lateral root stem cell niches in the different root types of maize during early development. Moreover, we will (ii) elucidate the plasticity of gene expression networks in phloem and xylem pole pericycle cells during early stem cell niche establishment in the different maize root types of wild-type and the mutant rum1 by a combination of laser capture microdissection (LCM) with RNA-seq. Subsequently, we will analyze the regulation of the transcriptomic landscape of these cell types with respect to developmental stage, genotype and root type. Finally, we aim to (iii) identify and characterize novel root type-specific mutants of lateral root stem cell niche establishment from candidate genes identified in the RNAseq experiment via our reverse genetic mutant repository. BonnMu.