Half-the Trna To Produce A Preliminary Study Of The Mechanism

Previously, our lab has set up a new method for cloning microRNA. Lots of half-tRNAs were identified accidently when we used this method to clone microRNA in human fetal liver. Through further experiment, we found half-tRNAs were ubiquity -ously expressed in eukaryotic cells. Then, how these half-tRNAs emerged and what caused them to be present largely in eukaryotic cells. So, we did some initial researches on the causes and mechaninsms that brought them about.In order to elucidate the biogenesis of half-tRNAs, we used mouse tissue, different types of eckaryotic cells as experimental materials and researched half-tRNAs production in different stress conditions through Northern blot assay using different probe complentary to 5'half-tRNAs, angiogenin-expressing vector, RNA interference, in vitro cleavage and so on. Our work acquired following results:1. Firstly indentified half-tRNAs in eukaryotic cells.2. Confirming half-tRNAs were ubiquitously expressed in different eukaryotic cells.3. As cells could produce half-tRNAs under various stress conditions, it meant that half-tRNAs might play an important role in the cell stress and was a stress reaction way aquired in organic evolution process.4. We firstly comfirmed angiogenin could cleavage the tRNAs and proposed a hypothesis of half-tRNAs biogenesis: stress condition stimulate cellsâ†'produce uncharged tRNAsâ†'enhance activity of ANG nucleaseâ†'produce half-tRNAsâ†'participate in cell stress reaction.Our research firstly identified half-tRNAs in eukaryotic cells and clarified the partial mechanism of their biogenesis. These works will lay a solid foundation for further research on the mechanism of half-tRNAs' biogenesis.