Levy B, Dixon G H
Biochemistry. 1977 Mar 8;16(5):958-64. doi: 10.1021/bi00624a023.
We have compared the sequence complexity and diversity of polyadenylated cytoplasmic RNA derived from two differentiated trout tissues: liver and testis. The kinetics of hybridization of polyadenylated RNA from each of these tissues with complementary DNA synthesized by reverse transcriptase revealed three abundance classes for liver RNA, the first comprising 4 sequences, the second 120, and the third, 20 000; in contrast, testis RNA showed only two abundance classes containing 6 and 6100 different RNA sequences, respectively and of average length 6 x 10(5) daltons. The extent of overlapping among those two RNA populations was further studied by performing heterologous annealing reactions between cDNA and a vast excess of mRNA. Liver mRNA was complementary to 80% of the testis cDNA. Conversely, testis mRNA reacted with only 25% of the liver cDNA. Experiments with fractionated cDNA probes indicated that the unshared sequences belonged mainly to the less frequent, most complex, class of mRNAs.
我们比较了源自两种分化的 trout 组织(肝脏和睾丸)的多聚腺苷酸化细胞质 RNA 的序列复杂性和多样性。这些组织中每种组织的多聚腺苷酸化 RNA 与逆转录酶合成的互补 DNA 的杂交动力学显示,肝脏 RNA 有三个丰度类别,第一类包含 4 个序列,第二类包含 120 个序列,第三类包含 20000 个序列;相比之下,睾丸 RNA 仅显示两个丰度类别,分别包含 6 个和 6100 个不同的 RNA 序列,平均长度为 6×10⁵ 道尔顿。通过在 cDNA 和大量过量的 mRNA 之间进行异源退火反应,进一步研究了这两个 RNA 群体之间的重叠程度。肝脏 mRNA 与 80% 的睾丸 cDNA 互补。相反,睾丸 mRNA 仅与 25% 的肝脏 cDNA 反应。用分级分离的 cDNA 探针进行的实验表明,未共享的序列主要属于频率较低、最复杂的 mRNA 类别。