Understanding the Abscisic Acid Pathway Using Guard Cell Specific Genes and the Anti-Aging Drug Spermidine

Abstract

Plants must respond to environmental stress including drought and harsh winters. Overcoming these stresses depend heavily on timing of stomatal closure and seed germination. My research focused on both chemical and genetic aspects involved in the abscisic acid pathway that controls both stomatal closures in leaves and seed germination in Arabidopsis thaliana. My first study focused on recognizing specific proteins involved in the abscisic acid pathway for stomatal guard cell closure. Given specific promoters for their respective proteins, it is possible to determine whether or not proteins are guard cell specific. GatewayTM technology utilizes a series of reactions to create a clone containing a promoter of interest called an expression vector. By injecting this vector directly into the leaf of Arabidopsis, the plant will use the promoter to create the guard cell specific protein. The second study examined the effect of the anti-aging drug Spermidine on seed sensitivity to abscisic acid concentration during seed germination. By varying the concentration of Spermidine and abscisic acid exposure to seeds then observing the number of surviving seeds, the effects of Spermidine on seed germination can be measured. Spermidine is expected to reduce seed sensitivity to abscisic acid leading to increased seed germination.