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:1978
卷号:75
期号:10
页码:4868-4872
DOI:10.1073/pnas.75.10.4868
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Virion RNA of poliovirus type 1 has been analyzed for the linkage between genome-protein VPg and the polyribonucleotide chain. Hydrolysis of the linkage with acid or alkali and enzymatic degradation lead to the conclusion that the bond is neither a phosphodiester such as nucleotidyl-(P-O)-serine (or threonine) nor a phosphoramidate such as nucleotidyl-(P-N)-amino acid. VPg-RNA can be iodinated by the Bolton and Hunter reagent [iodinated 3-(4-hydroxyphenyl)propionic acid N-hydroxysuccinimide ester] but not by the chloramine-T or lactoperoxidase procedures, an observation suggesting that VPg does not contain accessible tyrosine. However, VPg can be labeled with [3H]tyrosine in vivo. Hydrolysis of VPg-[32P]pUp with 5.6 M HCl at 110 degrees yielded 32P-labeled O4-(3'-phospho-5'-uridylyl)tyrosine that could be cleaved with micrococcal nuclease to O4-[32P]phosphotyrosine and uridine 3'-[32P]phosphate. These data establish that VPg is linked to the poliovirus genome by a bond between the O4 of tyrosine and the 5'-P atom of the terminal uridylic acid residue. The 5' end of polio genome RNA can now be described as VPg(Tyr-O)-pU-U-A-A-A-A-C-A-G.