Weiss S R, Bratt M A
J Virol. 1974 Jun;13(6):1220-30. doi: 10.1128/JVI.13.6.1220-1230.1974.
Polyadenylate [poly(A)] sequences are associated with the 35 and 50S Newcastle disease virus (NDV)-specific RNAs as well as all six to seven of the 18-22S NDV-specific messenger RNAs extracted from infected chicken embryo cells. The poly(A) associated with the 18-22S RNA has an average size of 120 to 130 nucleotides. The 18-22S RNA synthesized in vitro by NDV's virion-bound polymerase contains six to seven species of the same size and relative proportions as its intracellular counterpart. This in vitro synthesized 18-22S RNA also contains covalently linked poly(A) sequences which, although variable in size, are usually larger and more heterogeneous than those from the infected cell. In vitro RNA synthesis is supported not only by magnesium (at an optimal concentration of mM) but by manganese (at an optimal concentration of 0.5 to 1.0 mM) as well. However, the major product made in the presence of manganese, although sedimenting at 18 to 22S, differs somewhat from the product made in the presence of magnesium.
聚腺苷酸[poly(A)]序列与35S和50S新城疫病毒（NDV）特异性RNA以及从感染鸡胚细胞中提取的18 - 22S NDV特异性信使RNA中的所有六到七种相关。与18 - 22S RNA相关的聚腺苷酸平均大小为120至130个核苷酸。由NDV病毒体结合的聚合酶在体外合成的18 - 22S RNA包含六种到七种与细胞内对应物大小和相对比例相同的种类。这种体外合成的18 - 22S RNA还包含共价连接的聚腺苷酸序列，尽管其大小可变，但通常比感染细胞中的聚腺苷酸序列更大且更具异质性。体外RNA合成不仅由镁（最佳浓度为mM）支持，也由锰（最佳浓度为0.5至1.0 mM）支持。然而，在锰存在下产生的主要产物，尽管沉降系数为18至22S，但与在镁存在下产生 的产物略有不同。
