Yokoe S, Tanaka M, Hibasami H, Nagai J, Nakashima K
J Biochem. 1983 Dec;94(6):1803-8. doi: 10.1093/oxfordjournals.jbchem.a134532.
Tobacco mosaic virus RNA, forming 40S or 80S initiation complexes with wheat germ ribosomes, was covalently bound to 18S ribosomal RNA by the photoreaction with an RNA cross-linking agent, 4'-aminomethyl-4,5',8-trimethylpsoralen (AMT). Synthetic polyribonucleotide, poly(A, U), with the cap structure m7GpppGmC at the 5'-terminal was also cross-linked to 18S ribosomal RNA in 40S or 80S complexes with ribosomes by the AMT photoreaction. Polyuridylic acid with the same 5'-cap structure, forming 40S complexes but not 80S complexes with ribosomes, was most efficiently cross-linked to 18S ribosomal RNA by the psoralen photoreaction. These results suggest that the interactions between mRNA and 18S rRNA are not necessarily of strict complementarity but occur during formation of the complexes in eukaryotes. The 40S complexes would be then converted to 80S complexes in the presence of the AUG initiation codon or AUG-like triplets containing A and U on the polyribonucleotide chains which interact with 18S ribosomal RNA.
烟草花叶病毒RNA与小麦胚芽核糖体形成40S或80S起始复合物，通过与RNA交联剂4'-氨甲基-4,5',8-三甲基补骨脂素（AMT）的光反应共价结合到18S核糖体RNA上。具有5'-末端帽结构m7GpppGmC的合成多聚核糖核苷酸聚（A，U），也通过AMT光反应在与核糖体形成的40S或80S复合物中与18S核糖体RNA交联。具有相同5'-帽结构的聚尿苷酸与核糖体形成40S复合物但不形成80S复合物，通过补骨脂素光反应最有效地与18S核糖体RNA交联。这些结果表明，mRNA与18S rRNA之间的相互作用不一定具有严格的互补性，而是在真核生物复合物形成过程中发生。然后，在多聚核糖核苷酸链上与18S核糖体RNA相互作用的AUG起始密码子或含有A和U的AUG样三联体存在的情况下，40S复合物将转化为80S复合物。
