Open AccessThe sup-7(st5) X gene of Caenorhabditis elegans encodes a tRNATrpUAG amber suppressor.
Author(s) -
Suzanne L. Bolten,
Patricia Powell-Abel,
David A. Fischhoff,
Robert H. Waterston
Publication year - 1984
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.81.21.6784
Subject(s) - biology , gene , genetics , caenorhabditis elegans , transfer rna , microbiology and biotechnology , lambda phage , genomic dna , sequence analysis , rna , bacteriophage , escherichia coli
In earlier studies, we identified in Caenorhabditis elegans two informational suppressors sup-5 III and sup-7 X and recently showed that these suppressors acted via an altered tRNA to suppress translational termination at amber (UAG) stop codons. We now show that the sup-7 (st5) suppressor is a tRNATrpUAG amber suppressor. These studies utilized a radiolabeled purified tRNA fraction to identify hybridizing genomic sequences in a phage genomic library. DNA sequence analysis of the hybridizing segment of one clone showed that the probe recognized a tRNATrpUGG sequence. The sup-7 gene was shown to be one of an 11 or 12 member tRNATrp family by Southern blot analysis, taking advantage of an Xba I restriction site induced in the anticodon sequence by the mutational event to suppressor. Sequence analysis of a recombinant lambda clone containing sup-7 gene proved that sup-7(st5) is a tRNATrpUAG. This conclusive proof of the nature of sup7(st5) will permit unambiguous interpretation in genetic applications, and the availability of the cloned sequences may allow the sup-7 gene to be used to select for the reintroduction of DNA into C. elegans.