Interaction of Eukaryote Initiator Methionyl-tRNA with the Eukaryote Equivalent of Bacterial Elongation Factor T and Guanosine Triphosphate

The initiator tRNA, methionyl-tRNA(i) (Met), of yeast and wheat germ forms relatively unstable ternary complexes with their corresponding elongation factors T and GTP. Such complexes can be demonstrated only with fast separation techniques such as Sephadex G-50 and Millipore filtration, but not with the slow Sephadex G-100 method, although both techniques yield stable ternary complexes with all other aminoacyl-tRNAs, including the internal Met-tRNA(m) (Met). To bind yeast-initiating Met-tRNA(i) (Met) to ribosomes, initiation factors present in a ribosomal wash fraction from yeast are needed.