期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1979
卷号：76
期号：7
页码：3289-3293
DOI：10.1073/pnas.76.7.3289
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Transfer RNA (tRNA) molecules have been labeled with 32P at the 5' end and subjected to S1 nuclease digestion. The products were analyzed by high-resolution gel electrophoresis. Three initiator tRNAs and six chain-elongating tRNAs were examined. S1 nuclease cleaved Escherichia coli tRNAfMet, yeast tRNAfMet, and mammalian tRNAfMet at the same two positions in the anticodon loop. In contrast, S1 nuclease cleaved the anticodon loop of E. coli tRNAmMet, yeast tRNAmMet, yeast tRNAPhe, Schizosaccharomyces pombe tRNAPhe, E. coli tRNA2Glu, and E. coli tRNATrp (su+) at four positions generally, except where a modified nucleotide in the wobble position inhibited the enzyme. The marked contrast between these cleavage patterns suggests a different conformation for the anticodon loops of these two classes of tRNA molecules. It is suggested that the specialized conformation in the anticodon loop of initiator tRNAs may be due to a special sequence of GC base pairs in the adjoining anticodon stem.
