tRNA-mediated protein engineering

Novel methods of incorporating non-native amino acids and stable isotope la bels into proteins using modified tRNAs present new opportunities for basic research and biotechnology that go beyond conventional site-directed mutag enesis. tRNA-mediated protein engineering relies on the development of nove l tRNAs and their misacylation with custom-designed amino acids, the recogn ition of special codons by the tRNAs, and the efficient expression of these modified proteins. Recent progress has been made in all these areas, inclu ding the development of more effective suppresor tRNAs and higher yield tra nslation systems, leading to a variety of novel applications.