Tetrahymena thermophila glutamine tRNA and its gene that corresponds to UAA termination codon.

Publisher Website
Google Scholar
Abstract
Nucleotide sequence analysis of 1 of several tRNA genes cloned from T. thermophila macronuclear DNA indicated that it corresponds to a tRNA species having TTA as anticodon. The tRNA species corresponding to that gene was isolated and its nucleotide sequence was determined by post-labeling techniques. The nucleotide sequence was pG-G-U-U-C-C-A-U-A-m2G-U-A-.PSI.-A-G-D-G-G-D-D-A-G-U-A-C-U-G-G-G-G-A-Cm-U-Um-U-A-i6A-A-.PSI.-C-C-C-U-U-G-A-C-m5C-U-G-G-G-U-.PSI.-C-G-m1A-A-U-C-C-C-A-G-U-G-G-G-A-C-C-U-C-C-AOH. This tRNA sequence exactly matched the DNA sequence of the corresponding tRNA gene. The 1st position of anticodon is 2''0-methyluridine (Um), forming UmUA as the anticodon, which presumably recognizes the ochre termination codon UAA. This tRNA species is aminoacylated with glutamine by a Tetrahymena crude aminoacyl tRNA synthetase fraction, suggesting that ochre termination codon is used as a glutamine codon during cytoplasmic protein synthesis in Tetrahymena.