期刊
RNA
卷 6, 期 12, 页码 1727-1736出版社
COLD SPRING HARBOR LAB PRESS, PUBLICATIONS DEPT
DOI: 10.1017/S1355838200000996
关键词
18S ribosomal RNA; decoding site; human ribosomes; mRNA analogs; photocrosslinking
The 18S rRNA environment of the mRNA at the decoding site of human 80S ribosomes has been studied by crosslinking with derivatives of hexaribonucleotide UUUGUU (comprising Phe and Val codons) that carried a perfluorophenylazide group either at the N7 atom of the guanine or at the C5 atom of the 5'-terminal uracil residue. The location of the codons on the ribosome at A, P, or E sites has been adjusted by the cognate tRNAs. Three types of complexes have been obtained for each type derivative, namely, (1) codon UUU and Phe-tRNA(Phe) at the P site (codon GUU at the A site), (2) codon UUU and tRNA(Phe) at th, P site and PheVal-tRNA(Val) at the A site, and (3) codon GUU and Val-tRNA(Val) at the P site (codon UUU at the E site). This allowed the placement of modified nucleotides of the mRNA analog at positions -3, +1, or +4 on the ribosome. Mild UV irradiation resulted in tRNA-dependent crosslinking of the mRNA analogs to the 18S rRNA. Nucleotide G961 crosslinked to mRNA position -3, nucleotide G1207 to position +1, and A1823 together with A1824 to position +4. All of these nucleotides are located in the most strongly conserved regions of the small subunit RNA structure, and correspond to nucleotides G693, G926, G1491, and A1492 of bacterial 16S rRNA. Three of them (with the exception of G1491) had been found earlier at the 70S ribosomal decoding site. The similarities and differences between the 16S and 18S rRNA decoding sites are discussed.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据