Hashimoto S, Sakai M, Muramatsu M
Biochemistry. 1975 May 6;14(9):1956-64. doi: 10.1021/bi00680a024.
Simple two-dimensional thin-layer chromatography was found to be useful for the separation of sugar methylated dinucleotides in RNA. Of the 16 possible sequences of the type Nm-Np, 15 were separated and all the sequences were determined. In a mouse hepatoma, MH 134, the levels of the sugar methylation in the 18S and 28S RNA molecules were 17-18 and 11-12 per 1000 nucleotides, respectively. Thus, 18s RNA contained approximately 35 2'-O-methylated dinucleotides and 28S RNA approximately 60 2'-O-methylated dinucleotides. The pattern of distribution was also distinct between these two molecules. Two 2'-O-methylated trinucleotides were identified in the 28S RNA with the sequences Um-Gm-Up and Um-Gm-psip. A unique 2'-O-methylated tetranucleotide was present also in the 28S RNA, the sequence of which was Am-Gm-Cm-Ap. The 5'-terminal nucleotides of both 18S and 28S RNA were obtained as nucleoside 3',5'-diphosphates (pNp) in the trinucleotide fraction of the RNase T2 digest. The 5'-termimi of 18S and 28S RNA were pUp and pCp, respectively, and found to be almost homogeneous.
已发现简单的二维薄层色谱法可用于分离RNA中的糖甲基化二核苷酸。在Nm-Np类型的16种可能序列中，分离出了15种，并确定了所有序列。在小鼠肝癌MH 134中，18S和28S RNA分子中的糖甲基化水平分别为每1000个核苷酸17 - 18个和11 - 12个。因此，18S RNA含有约35个2'-O-甲基化二核苷酸，28S RNA含有约60个2'-O-甲基化二核苷酸。这两种分子之间的分布模式也不同。在28S RNA中鉴定出两种2'-O-甲基化三核苷酸，序列分别为Um-Gm-Up和Um-Gm-ψp。在28S RNA中还存在一种独特的2'-O-甲基化四核苷酸，其序列为Am-Gm-Cm-Ap。18S和28S RNA的5'-末端核苷酸在RNase T2消化产物的三核苷酸部分中以核苷3',5'-二磷酸（pNp）的形式获得。18S和28S RNA的5'-末端分别为pUp和pCp，且发现几乎是均一的。
