Cortical Microtubule Patterning in the Arabidopsis Hypocotyl

Indiana University, Bloomington IN

Investigators

Abstract

Plants adjust their growth plan to maximize exposure to resources. A central tool in this adaptive program is the rapid extension of stems and roots. Plants grow toward the sun or toward richer soils through careful re-orientation of their apical meristems, the stem-cell generating portions of the plant. This project focuses on the fundamental properties of cellular growth processes critical to morphogenesis. Using genetic analysis, computational models, and leading-edge microscopy techniques, this work will reveal how the internal polymer systems in the cell spatially organize in response to plant hormones to direct axial cell growth. The microtubule cytoskeleton has a fundamental role in orchestrating the axial morphogenesis of plants through its ability to influence the mechanical properties of the cell wall. Microtubules organize into patterns just beneath the cell membrane that determine where cellulose microfibrils are deposited into the cell wall. By creating co-oriented cellulose patterns, the microtubules bias cells toward axial extension. The goal of the project is to discover the genes and molecular mechanism that lead to specific microtubule patterns and the transfer of that information to the cell wall. To accomplish that goal, genetic screening and cell biological tools will be combined to determine how plant hormone receptors trigger microtubule array patterning and how the patterning of the microtubules is integrated with cell expansion.