Interesting and unusual features in the sequence of Neurospora crassa [Fungi] mitochondrial tyrosine transfer RNA

• Published in: Proceedings of the National Academy of Sciences - PNAS 1979-02, Vol.76 (2), p.717-721
• Main Authors: Heckman J.E, Alzner Deweerd B, RajBhandary U.L
• Format: Article
• Language: English
• Subjects: Acetates; Base Sequence; Biological Evolution; DNA, Mitochondrial - genetics; Mitochondria; Neurospora - genetics; Neurospora crassa - genetics; Nucleic Acid Conformation; Nucleic acids; Nucleotides; Oligonucleotides; Purines; Ribonucleotides - analysis; RNA, Transfer - genetics; Room temperature; Sequence analysis; Transfer RNA; Tyrosine; Yeasts
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.76.2.717

The mitochondrial tyrosine tRNA from Neurospora crassa has been sequenced and found to have several interesting features: (i) It resembles prokaryotic rather than eukaryotic tyrosine tRNAs in that it possesses a large variable loop (loop III); moreover, it can be quantitatively aminoacylated by Escherichia coli tyrosyl-tRNA synthetase but not by yeast tyrosyl-tRNA synthetase. (ii) This tRNA differs from all tRNAs sequenced to date in lacking the A residue at position 14 and the constant purine residue at position 15, two nucleosides that have been found so far in loop I of all tRNAs and that have been implicated in base-base tertiary interactions, respectively, with the universal U residue at position 8 and the constant pyrimidine residue at the end of loop III. (iii) Unlike the N. crassa mitochondrial initiator tRNA, this tRNA contains the usual TΨ C sequence in loop IV and the highly conserved GG sequence in loop I common to other tRNAs.