Prof. Akira Kaji

Professor Akira Kaji is a professor of microbiology, School of Medicine, University of Pennsylvania, Philadelphia, USA. He contributed to the deciphering of genetic code by his discovery of the fact that the complex of poly-U with ribosome binds specifically tRNA specific for phenylalanine. He also discovered RRF.

The following is a short review of Akira Kaji past work. In 1963, they discovered that specific tRNA binds to the complex of mRNA and ribosome. This finding was essential to decipher the genetic code (9). Regarding RRF, upon in vivo inactivation of RRF, the ribosome starts the unscheduled translation downstream from the termination codon. Crystal structure by X-ray crystallography as well as solution structure by NMR has revealed that RRF is a near perfect structural mimic of tRNA. Indeed, we found that RRF functionally mimics tRNA in that it moves in the inter-subunits space like tRNA does. However, the mode of RRF binding to the ribosome is different from that of tRNA. We also discovered arginyl-tRNA protein transferase in 1963(10). This enzyme is an essential for higher eukaryotes and involved in post-translational protein modification.