Cytokinins are hormones vital for plant growth. They control cell division, the development of water and nutrient transport systems and the aging process of leaves and stems. This project aims to investigate how plant cells respond to cytokinin, and it will focus on a negative control mechanism known as feedback-inhibition. Feedback-inhibition is an essential part of a hormone response pathway because it allows cells to limit the strength and the duration of a response, allowing rapid readjustments to changes in hormone concentration. Previous research has shown that cytokinin sensing leads to the activation of a family of cytokinin response activator proteins, the type-B Arabidopsis Response Regulators (B-ARRs). The investigators have found that one member of this group is rapidly degraded upon its activation. The main goals of this project are to develop a detailed understanding of this feedback-inhibition mechanism, and to determine to what extent it controls different members of the B-ARR family. The proposed research is predicted to yield novel insight into the fine-tuning of an essential plant hormone response pathway and thus will be valuable for the broader area of hormone regulation biology.
The combination of genetics, biochemistry, molecular biology and physiology makes this project an attractive training environment for a postdoctoral scientist, technician and undergraduate students. This work also has potential implications for agriculture since cytokinins control several processes that impact crop yields. Therefore, an improved understanding of cytokinin signaling will provide new tools for the engineering of crop species aimed at introducing beneficial traits.
