分离出一种小鼠DNA组分，其编码的信息性RNA序列多于非信息性RNA序列。

Isolation of a mouse DNA fraction which encodes more informational than non informational RNA sequences.

作者信息

Hanania N, Shaool D, Harel J

出版信息

Mol Biol Rep. 1982 Mar 31;8(2):91-6. doi: 10.1007/BF00778510.

Abstract

A small fraction of single-stranded DNA (ssDNA), amounting to 1.5--2% of the total DNA, was isolated from native nuclear DNA of mouse Ascites tumour cells. In RNA-driven annealing reactions, 40--42% of the ssDNA, (labelled with [3H]-thymidine or 125I) could be hybridized to cytoplasmic RNA was compared with 4--4.5% for the non repetitious component of bulk DNA and 60--63% of the ssDNA could be hybridized to nuclear RNA as compared with 20--22% for bulk DNA. It was also found that most of the ssDNA sequences which are hybridizable to homologous RNA, consisted of non self-reassociating DNA regions (which can be reassociated with non repetitious bulk DNA). These findings complete earlier data obtained in other cell systems and demonstrate that ssDNA mainly originates from active DNA transcription sites which encode informational RNA sequences. It is proposed that ssDNA is formed via selective endogenous nuclease attacks presumably at an early stage of the DNA purification procedure.

摘要

从小鼠腹水肿瘤细胞的天然核DNA中分离出一小部分单链DNA（ssDNA），其占总DNA的1.5% - 2%。在RNA驱动的退火反应中，（用[³H] - 胸腺嘧啶核苷或¹²⁵I标记的）40% - 42%的ssDNA可与细胞质RNA杂交，而大量DNA的非重复组分的杂交率为4% - 4.5%；60% - 63%的ssDNA可与核RNA杂交，而大量DNA的杂交率为20% - 22%。还发现，大多数可与同源RNA杂交的ssDNA序列由非自我重缔合的DNA区域组成（这些区域可与非重复的大量DNA重缔合）。这些发现完善了在其他细胞系统中获得的早期数据，并表明ssDNA主要源自编码信息RNA序列的活性DNA转录位点。有人提出，ssDNA可能是在DNA纯化过程的早期阶段通过选择性内源性核酸酶攻击形成的。