Microarray analysis of estradiol-regulated genes in Arabidopsis thaliana seedlings

Steroids are well-known regulators of physiological processes in plants and animals. The only known plant steroid hormones are brassinosteroids. Earlier studies demonstrated that animal steroid hormones have signaling activities in plants. The goal of this study was to determine the regulatory effects of estradiol on Arabidopsis gene expression. Seedlings were treated with 10 nM 17β-estradiol for three hours at the end of the seven-day cultures in liquid Murashige and Skoog medium. RNA was isolated from estradiol-treated and control plants and used for microarray analyses. From a total of 212 selected genes, 35% were up-regulated, 52% down-regulated and 13% non-responsive to estradiol treatment. Gene expression was altered mostly for secondary metabolism and CYP450 genes. Stress related genes were up-regulated indicating a possible synergistic effect of estradiol in plant growth and stress responses. Estradiol did not affect brassinosteroid biosynthesis genes. This study will help understand the steroid hormone and xenobionts effects on plants.