Ab G, Malt R A
J Cell Biol. 1970 Aug;46(2):362-9. doi: 10.1083/jcb.46.2.362.
The labile precursors of ribosomal RNA in mouse kidney are preserved when nuclei rapidly isolated after sieving through multiple screens are swollen and cleansed in the presence of an RNase inhibitor before digestion with DNase and phenol extraction. The kinetics of nucleolar labeling analyzed on polyacrylamide gels show that 36S RNA is the major intermediate product in the catabolism of the original 45S RNA precursor to 32S RNA, from which 28S RNA is derived. Each kidney nucleus contains about 200-600 molecules of 45S RNA; the turnover time of the 45S pool is about 3 +/- 2 min. Compared with HeLa cells, kidney nuclei have a different major intermediate product and a much smaller and more rapidly turning-over pool of ribosomal precursor RNA.
当通过多层筛网快速分离出的小鼠肾脏细胞核在核糖核酸酶抑制剂存在的情况下肿胀并清洗后,再用脱氧核糖核酸酶消化并进行酚抽提时,核糖体核糖核酸的不稳定前体得以保留。在聚丙烯酰胺凝胶上分析核仁标记的动力学表明,36S核糖核酸是原始45S核糖核酸前体分解代谢为32S核糖核酸的主要中间产物,而28S核糖核酸则来源于32S核糖核酸。每个肾脏细胞核含有约200 - 600个45S核糖核酸分子;45S核糖核酸库的周转时间约为3±2分钟。与海拉细胞相比,肾脏细胞核具有不同的主要中间产物,并且核糖体前体核糖核酸库要小得多且周转更快。