(IMAGE) Nara Institute of Science and Technology Caption The fruit fly lacks the tRNA nuclear export receptor Exportin-t, which only exports end-processed tRNAs to the cytoplasm to ensure the completion of the processing steps in the nucleus. The related protein Exportin-5 is known to be responsible for tRNA nuclear export in the fly, but whether it is selective for end-processed tRNAs remained unknown. Researchers unexpectedly found that fly Exportin-5 preferentially binds tRNA precursors before end-processing, and end-processing occurs in the cytoplasm after nuclear export of tRNA precursors, unlike the yeast tRNA processing mechanism. Credit Katsutomo Okamura Usage Restrictions Credit required License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.