Plant hormones are small signaling molecules that direct key processes in plants’ development and adaptive growth, including in crop species. For example, during the so-called 'green revolution', high-yielding cultivars of maize, wheat, and rice, which revolutionized these grains world productivity, were identified as mutants in biosynthesis or signaling of the plant hormone gibberellin. Thus, understanding the details of gibberellins dynamics in plants has significant research importance with potential practical implications on agriculture, food security and human health. To date, very little information exists on how plants regulate the movement of gibberellins to insure their arrival in the right place, time and concentration so that proper growth and development can be achieved.
The overall goal of the proposed research was to elucidate and characterize GA flow in plants and identify the mechanisms controlling it.
Towards this goal, we developed several tools that facilitate imaging and manipulation of gibberellins in live, whole plants, Using these tools, we and others were able to map accumulation sites of gibberellins in different plant species and identify several gibberellins transporters, including the first one to be validated in planta.
The main conclusion from the project is that gibberellins are indeed actively transported in plants and that an elaborate transport mechsnim to control their flow exists. This discoery not only has fundamental implications for basic research of gibberellins, but also has potential practical applications. Gibberellins regulate many important traits in crops and the abiliy to influence on their function via intervention in transport opens the door for development of novel agrochemicals for agricultural use.
