GreenLincs · Functional roles of long noncoding RNAs in drought stress responses of Arabidopsis

In the coming decade declining water availability will exert increasing pressure on crop productivity worldwide. One of the solutions is to breed crop plants with enhanced drought tolerance. Whilst plant breeders are continuing to make progress in this direction, elucidation of the molecular basis of drought stress will help not only traditional breeding efforts but also formulate new transgenic strategies to produce plants with enhanced adaptability under conditions of water limitation.The traditional view that protein coding genes are the only regulatory elements in the genome has been challenged by the discovery of miRNA genes and more recently by the discovery of transcription units producing long intergenic non-coding (linc)RNAs. Recent work in yeast and mammals indicate that these lincRNAs play important roles in cell differentiation, organ development and responses to stress. Still, very little is known about plant lincRNAs.In this proposal we will use the model dicot plant, Arabidopsis, to investigate several novel molecular aspects of drought stress while providing the applicant advanced training in scientific and complementary skills to substantially enhance career development. We will first identify and characterize in detail lincRNAs whose expression levels are changed in response to drought. Preliminary results from Prof. Nam-Hai Chua’s lab (outgoing host) have uncovered more than a few hundred lincRNA genes that belong to this category and whose functions await discovery. This is a potential class of genes that may orchestrate drought responses by the epigenetic regulation of gene expression. Manipulation of the expression levels of these candidate lincRNAs will uncover their possible functions and analysis of chromatin modifications and neighboring gene expression will provide insights into their epigenomic mode of action under drought stress, potentially providing new candidate genes for genetic engineering in crop plants.