Tibbetts C, Pettersson U, Johansson K, Philpson L
J Virol. 1974 Feb;13(2):370-7. doi: 10.1128/JVI.13.2.370-377.1974.
The complementary strands of adenovirus type 2 (Ad2) DNA were separated by buoyant density gradient centrifugation with poly (U, G). The complementary strand DNA was shown to remain intact through the course of strand separation. The l-strand of Ad2 DNA, appearing in the less dense complex with poly (U, G) in neutral CsCl density gradients, was shown to have a buoyant density in alkaline (pH 12.5) CsCl density gradients which is 2 to 3 mg per ml greater than that of its complement (h-strand). Renaturation of purified complementary strand DNA was observed only in mixtures of h- and l-strand DNA, and then with the second-order reaction rate expected for Ad2 DNA. Hybridization of the complementary strands of Ad2 DNA with cytoplasmic mRNA isolated from infected HeLa cells was performed in liquid phase and analyzed by hydroxylapatite chromatography. Before viral DNA synthesis (6 h after infection), 13 to 18% of the h-strand and 30 to 35% of the l-strand were represented in viral mRNA. Late (18 h) after infection the mRNA represented 20 to 25% and 63 to 68% of the h- and l-strands, respectively. Most, if not all sequences present in viral mRNA before viral DNA synthesis were also present in the cytoplasm late in infection.
用聚（U，G）通过浮力密度梯度离心法分离2型腺病毒（Ad2）DNA的互补链。结果表明，互补链DNA在链分离过程中保持完整。在中性CsCl密度梯度中，Ad2 DNA的l链与聚（U，G）形成密度较小的复合物，在碱性（pH 12.5）CsCl密度梯度中，其浮力密度比其互补链（h链）高2至3 mg/ml。仅在h链和l链DNA的混合物中观察到纯化的互补链DNA的复性，且复性反应速率符合Ad2 DNA的二级反应速率。Ad2 DNA的互补链与从感染的HeLa细胞中分离的细胞质mRNA在液相中进行杂交，并通过羟基磷灰石色谱法进行分析。在病毒DNA合成之前（感染后6小时），病毒mRNA中h链的占比为13%至18%，l链的占比为30%至35%。感染后期（18小时），mRNA中h链和l链的占比分别为20%至25%和63%至68%。在病毒DNA合成之前存在于病毒mRNA中的大多数（如果不是全部）序列在感染后期的细胞质中也存在。
