The research project aims to focus on studies concerning the structure, and relationship between the structure and function of transfer ribonucleic acids (tRNA). The general or specific recognition of tRNAs by a variety of components of the protein synthesizing machinery, including in particular the specific interaction between an aminoacyl tRNA synthetase and the corresponding tRNA will be studied. Initiator tRNAs and the mechanism by which these tRNAs carry out the unique function of initiation of protein synthesis will be studied. The role of tRNAs in genetic suppression in eukaryotic systems and miscellaneous function of tRNAs will be investigated. The biosynthesis of modified nucleosides in tRNAs will be studied and attempts will be made to isolate, purify and examine in detail several of the enzymes involved in this step. The role of the modified nucleosides in tRNAs for the function of these tRNAs in protein biosynthesis will be studied. It is hoped that these studies will lead to a better understanding of the mechanism by which tRNAs play such an important role in genetic information transfer and probably genetic regulation. BIBLIOGRAPHIC REFERENCES: Transfer RNA -- Sequence, Molecular Structure and Properties. A. Rich and U.L. RajBhandary, Ann. Rev. Biochem., in the press, 1976. Coding Properties, Anticodon Sequences and Classification of tRNAs of Known Sequences. U.L. RajBhandary, Handbook of Cell Biology, in the press, 1976.