Harvey R J
J Bacteriol. 1975 Dec;124(3):1330-43. doi: 10.1128/jb.124.3.1330-1343.1975.
Sedimentation distributions of rapidly labeled ribonucleic acid (RNA) in extracts prepared from cells labeled for 60 s or less with [3H]uridine showed that the immature ribosome precursor particles themselves have an RNA precursor which sediments with polyribosomes and 70s ribosomes. In extracts prepared from cultures labeled for 30 s, the fraction of labeled RNA which did not sediment with polyribosomes was much less than the fraction which was ribosomal RNA (rRNA). Rapidly labeled RNA associated with polyribosomes had a nucleotide base composition consistent with the presence of rRNA, and was shown by RNA-deoxyribonucleic acid hybridization to contain 30 to 40% rRNA. Nascent rRNA is thus associated with polyribosomes during its transcription. The sedimentation distribution of rapidly labeled 16s and 23s rRNA showed that these molecules are separated during transcription and associated with different polyribosomes.
用[³H]尿苷标记60秒或更短时间的细胞提取物中，快速标记的核糖核酸（RNA）的沉降分布表明，未成熟核糖体前体颗粒本身具有一种RNA前体，它与多核糖体和70S核糖体一起沉降。在标记30秒的培养物提取物中，不与多核糖体一起沉降的标记RNA部分远少于核糖体RNA（rRNA）部分。与多核糖体相关的快速标记RNA的核苷酸碱基组成与rRNA的存在一致，并且通过RNA-脱氧核糖核酸杂交表明其含有30%至40%的rRNA。因此，新生rRNA在转录过程中与多核糖体相关。快速标记的16S和23S rRNA的沉降分布表明，这些分子在转录过程中分离并与不同的多核糖体相关。
