This study will investigate a novel RNA-based mechanism that allows plants to respond to stress that affects the DNA, and to transmit a signal that protects chromosome integrity, which is important for plant fertility, growth and disease prevention. This project will develop fundamental knowledge valuable for breeding and growing healthier plants. This project will integrate basic plant science research with the teaching and training of the next-generation of plant scientists. As part of this effort, laboratory management workshops for postdoctoral fellows and new faculty will be conducted, and a graduate course on this topic will be developed.The overarching goal of this project is to elucidate the molecular mechanism and regulation of TER2, a novel telomerase-associated long noncoding RNA (lncRNA) from the model plant Arabidopsis thaliana. TER2 is a negative regulator of telomerase that is rapidly stabilized in response to DNA double-strand breaks. Induction of TER2 represses telomerase activity and is hypothesized to promote faithful repair of DNA damage. TER2 is also necessary for reproductive fitness through an unknown mechanism. A combination of biochemical, genetic, cell biological and computational strategies will be used to study TER2. Objective 1 will define key structural elements that regulate TER2 processing/metabolism for the purpose of identifying the DNA damage sensor within TER2 and the elements that control TER2 stability. Objective 2 will investigate the role of small RNA processing machinery in promoting TER2 turnover by testing if TER2 is a substrate for cleavage by Dicer 2. Objective 3 will examine the contribution of TER2 in Arabidopsis reproduction by testing whether the fertility-related defects in ter2 mutants reflect aberrant male gametogenesis or the effect of a paternally expressed imprinted gene. Altogether, the results of this work will establish new paradigms for lncRNA regulation and increase understanding of RNA-based pathways that promote genome stability.
