Updated on 29 May 2012
The laboratory of Dr Paul Verslues is working on plant responses to limited water supply during drought. Many plants accumulate large quantities of proline during drought; however, the adaptive value of proline has remained unclear. The Verslues laboratory, along with collaborators at the University of Texas, found that different types of Arabidopsis plant varied ten-fold in drought-responsive proline accumulation. Some of this variation was accounted for by high levels of a non-functional RNA produced by the gene encoding the proline synthesis enzyme 1-pyrroline-5-carboxylate synthetase1 (P5CS1).
Arabidopsis types having high levels of the non-functional P5CS1 RNA shared the same set of genetic changes that promoted alternative RNA splicing of P5CS1. These data demonstrated a novel source of RNA splicing variation in plants and correlation of P5CS1 variation with climate data indicated a role of P5CS1 and proline synthesis in adaptation to environments differing in water availability and temperature.
The results have implications in drought-adaptation and in how proline metabolism may be best targeted in biotechnology efforts to improve drought tolerance of crop plants.