Molecular Genetics of Cell Patterning in the Arabidopsis Root Epidermis

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

0779000 Schiefelbein All multicellular organisms must solve a fundamental problem during their development: How to generate different cell types from a single original cell? The research conducted in this project is designed to address this question and help uncover the molecular mechanisms used by living things to produce distinct cell types in appropriate patterns. This project employs a simple model system for studying cell fate specification; the formation of the root epidermis in the flowering plant Arabidopsis thaliana. The Arabidopsis root epidermis is exceptional because its two cell types are produced in a predictable position-dependent fashion. Furthermore, the root epidermis is formed continuously as the root grows, so the formation of the epidermal cells can be easily followed at all stages of development. Finally, plants that lack either root epidermal cell type are viable, enabling sophisticated genetic experimentation. In recent studies, four genes encoding putative transcriptional regulators (named TTG, WER, GL2, and CPC) have been found to control the patterning of the two epidermal cell types. It appears that the normal patterning of the cell types is due the appropriate production, distribution, and interaction of these regulators during root development. The research in the present project period is intended to: (1) more clearly define the interactions between the WER regulator and each of the other factors, (2) illuminate the functional relationship between the WER and a closely-related transcriptional regulator affecting shoot epidermis cell fate, and (3) uncover new regulators of epidermal cell patterning. The results of these studies are expected to provide a greater understanding of the molecules and mechanisms employed by Arabidopsis and multicellular organisms in general, to generate and regulate cellular diversity during development