EAPSI:Identifying Gene Networks that Control Root Hair Growth in Arabidopsis Thaliana

Clark Natalie M, Raleigh NC

Investigators

Abstract

Root hairs are outgrowths on plant roots that are responsible for absorbing water and nutrients from the soil. It is important for plants to control both the number and size of their root hairs so that they balance nutrient uptake and energy cost. If plants do not have enough root hairs, or their root hairs are too small, they cannot absorb enough nutrients to help them survive. Conversely, growing too many plant hairs causes the plant to expend more energy. Understanding the genes that control root hair growth and development can help scientists engineer plants that are able to survive in nutrient-deficient soils. This project will investigate the genetic and molecular mechanisms that control root hair growth and development in the model plant system Arabidopsis thaliana. This research will be conducted in collaboration with Dr. Keiko Sugimoto at the RIKEN Center for Sustainable Resource Science, who has extensive experience studying root hair development. Two transcription factors, GT2-LIKE 1 (GTL1) and its close homolog DF1, have been found to regulate root hair growth in A. thaliana: however, their direct targets and pathways remain unknown. Predictive Gene Regulatory Networks (GRNs) of GTL1 and DF1 will be constructed from gene expression data obtained from mutant and misexpression lines. These GRNs will be constructed using mathematical methods such as dynamic Bayesian networks and regression trees. The GRNs will then be used to predict targets of GTL1 and DF1 that are involved in root hair development. Potential targets of GTL1 and DF1 will be validated using available Chromatin ImmunoPrecipitation (ChIP) data as well as functional analysis. Understanding the pathways of GTL and DF1 will provide insight into the molecular mechanisms controlling root hair growth and development. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.