Balmain A, Krumlauf R, Vass J K, Birnie G D
Nucleic Acids Res. 1982 Jul 24;10(14):4259-77. doi: 10.1093/nar/10.14.4259.
A cDNA library has been prepared from mouse embryo small RNAs and screened for the presence of clones complementary to the highly abundant cytoplasmic 7S RNA. One clone (pA6) was selected which hybridized exclusively with 7S RNA on a Northern blot prepared from cytoplasmic RNA run on high resolution polyacrylamide/urea gels. Sequence analysis of this clone has shown that at least 65 nucleotides at the 5' end of 7S RNA are extensively homologous with the highly repeated mouse B1 family. Heterologous hybridisations between the cloned mouse 7S sequence and RNAs prepared from rat, human and chick cells have shown that the non-B1 part of the 7S RNA molecule has been highly conserved during recent eucaryotic evolution. There are multiple copies of 7S RNA genes in the genomes of mouse, human, rat and chick cells, but substantial differences exist in copy number and genomic organisation in these organisms.
已从小鼠胚胎小RNA制备了一个cDNA文库，并筛选了与高度丰富的胞质7S RNA互补的克隆的存在。选择了一个克隆（pA6），它在由在高分辨率聚丙烯酰胺/尿素凝胶上运行的胞质RNA制备的Northern印迹上仅与7S RNA杂交。对该克隆的序列分析表明，7S RNA 5'端至少65个核苷酸与高度重复的小鼠B1家族广泛同源。克隆的小鼠7S序列与从大鼠、人类和鸡细胞制备的RNA之间的异源杂交表明，7S RNA分子的非B1部分在最近的真核生物进化过程中高度保守。小鼠、人类、大鼠和鸡细胞的基因组中存在多个7S RNA基因拷贝，但这些生物体在拷贝数和基因组组织方面存在显著差异。
