Characterization of Suberin Biosynthesis and Deposition in Arabidopsis thaliana Roots

The polymer suberin plays a crucial role in plants, forming barriers that restrict and direct the flow of water, solutes and gases in the root endodermis. Since suberization of the root endodermis restricts loss of water and solutes, as well as uptake of toxins, the deposition of suberin is likely to be important for plant stress tolerance. Understanding this relationship could have practical agricultural implications, such as engineering drought tolerant plants.

The factors that influence developmental suberin deposition patterns are not well understood and their identification is at the core of the study. It was hypothesized that the localization of suberin directly depends on the chronological age of the root, as opposed to resulting from changing growth rates, and that this pattern will be the same in lateral roots. This hypothesis was tested by staining roots at different time points with Oil-Red-O to visualize suberin accumulation, and by measuring the growth rates of the roots to see if there was a correlation. In addition, the growth rates of Arabidopsisroots were modulated by growing seedlings on agar media containing various hormones and nutrients. In addition, the deposition patterns of lignin, a polymer that accumulates in the mature vascular tissue, root hairs and lateral roots, were documented to place the suberin data in a developmental context. To support the histological observations, quantitative PCR was performed with cDNA derived from longitudinal root sections to evaluate the expression of known suberin synthesis associated genes and to identify correlations with the suberin staining patterns. This study provides a broader understanding of Arabidopsis root development and the regulation of suberin deposition.

My Experience

Without being hyperbolic, I can say that the PGRP internship has been the most important experience in my development as a student of science. I’ve learned an incredible amount about specifics pertaining to my individual research, as well as fundamental lab techniques for generating and analyzing data. Most importantly, I better understand the nuisances of what it means to make good science happen. In one summer, I learned what it felt like to have hours of work yield undesirable results, as well as the legitimate thrill of acquiring solid data. I learned how to continue working effectively with the ups and the downs. This opportunity will prove to be a milestone in my current career as a student, and my future career as a scientist.