FRACTIONATION OF MITOCHONDRIAL RNA FROM HELA-CELLS BY HIGH-RESOLUTION ELECTROPHORESIS UNDER STRONGLY DENATURING CONDITIONS
FRACTIONATION OF MITOCHONDRIAL RNA FROM HELA-CELLS BY HIGH-RESOLUTION ELECTROPHORESIS UNDER STRONGLY DENATURING CONDITIONS
复制标题
DOI：
10.1016/0022-2836(78)90241-3
复制
发表时间：
1978-01-01
影响因子：
5.6
通讯作者：
ATTARDI, G
中科院分区：
文献类型：
--
作者：
AMALRIC, F;MERKEL, C;ATTARDI, G
在强变性剂甲基氢氧化汞存在下，用琼脂糖凝胶电泳法结合放射自显影技术，从HeLa人宫颈癌细胞中分离不同种类的~(32)P标记的线粒体RNA。在分子量为9倍的范围内，至少鉴定出18个含聚(A)的离散RNA组分和14个不含聚(A)的离散组分。104-3.4倍。106.异质分散的RNA，尤其是在凝胶的高相对分子质量区域，含量高达4.5倍。106，也观察到。对溴化乙锭的敏感性和对线粒体DNA的碱基序列同源性表明，所有离散成分和大部分异质RNA都来自线粒体DNA。含有从重线粒体DNA链转录而来的RNA组分的离散聚(A)[腺苷酸]的数量和大小使得它们的序列不能适应不被rRNA和tRNA基因占据的重链部分。这表明这些成分中的一些之间存在产物关系的前体，或重链片段的重叠转录。与轻线粒体DNA链杂交的异质成分的大小限制表明，这条链可能以长的、连续的分子的形式转录，这些分子在加工过程中经历逐渐缩短。
Electrophoresis through agarose slab gels in the presence of the strong denaturing agent methylmercuric hydroxide, in combination with autoradiography, was used in the present work to resolve different species of 32P-labeled mitochondrial RNA from HeLa human cervical cancer cells. At least 18 discrete poly(A)-containing RNA components and 14 discrete components lacking poly(A) were identified in the molecular weight range from 9 .times. 104-3.4 .times. 106. Heterodisperse RNA, especially abundant in the high molecular weight region of the gel, up to about 4.5 .times. 106, was also observed. The sensitivity to ethidium bromide and the base sequence homology to mitochondrial DNA of all the discrete components and a substantial portion of the heterogeneous RNA suggest their mitochondrial DNA origin. The number and size of the discrete poly(A) [adenylic acid] containing RNA components transcribed from the heavy mitochondrial DNA strand are such that their sequences cannot be accommodated in the portions of the heavy strand not occupied by the rRNA and tRNA genes. This indicates a precursor to product relationship between some of these components, or overlapping transcription of segments of the heavy strand. The size limit of the heterogeneous components hybridizing to the light mitochondrial DNA strand suggests that this strand may be transcribed in the form of long, continuous molecules, which undergo progressive shortening as a result of processing.