Thomason A R, Friderici K H, Velicer L F, Rottman F
J Virol. 1978 May;26(2):226-35. doi: 10.1128/JVI.26.2.226-235.1978.
The F-422 line of feline thymus tumor cells, chronically infected with the Rickard strain of feline leukemia virus (R-FeLV), was labeled with 32P, and the total cytoplasmic RNA was isolated. The RNA was centrifuged through sucrose gradients, and R-FeLV virus-specific RNA (vRNA) was located by hybridization of portions of the gradient fractions to R-FeLV complementary DNA. vRNA classes with average sedimentation coefficients of approximately 36S, 28S, 23S, and 15S were identified. Each class of RNA was recovered by hybridized with mercurated R-FeLV complementary DNA, and the hybrids were chromatographed on columns of sulfhydryl-Sepharose to separate them from unhybridized cellular RNA. Although insufficient amount of 36S and 28S vRNA were obtained for further analysis, the 23S and 15S VRNA classes were analyzed to determine the nature of their 5' termini. Each of these vRNA classes was found to contain stoichiometric amounts of cap structures per unit length of RNA, consistent with the presence of one cap per molecule. The structure of the 23S vRNA cap was found to be m7G5'ppp5'GmpAp, whereas that of the 15S vRNA cap was m7G5'ppp5'GmpGp.
长期感染猫白血病病毒里卡德株（R-FeLV）的猫胸腺肿瘤细胞F-422系用32P进行标记，然后分离出总的细胞质RNA。将该RNA通过蔗糖梯度离心，通过使梯度级分的部分与R-FeLV互补DNA杂交来定位R-FeLV病毒特异性RNA（vRNA）。鉴定出平均沉降系数约为36S、28S、23S和15S的vRNA类别。通过与汞化的R-FeLV互补DNA杂交回收每一类RNA，然后将杂交体在巯基琼脂糖柱上进行层析，以将它们与未杂交的细胞RNA分离。尽管获得的36S和28S vRNA量不足以进行进一步分析，但对23S和15S vRNA类别进行了分析，以确定其5'末端的性质。发现每一类这些vRNA在RNA的每单位长度中都含有化学计量的帽结构，这与每个分子存在一个帽一致。发现23S vRNA帽的结构为m7G5'ppp5'GmpAp，而15S vRNA帽的结构为m7G5'ppp5'GmpGp。
