Jacobson A, Firtel R A, Lodish H
Proc Natl Acad Sci U S A. 1974 May;71(5):1607-11. doi: 10.1073/pnas.71.5.1607.
Messenger RNA of the cellular slime mold, Dictyostelium discoideum, contains about equimolar amounts of two classes of poly(adenylic acid) [poly(A)]; one is about 25 nucleotides long and the second about 100 nucleotides long. At least half of the messenger RNA molecules contain one sequence each of poly(A)(25) and poly(A)(100); both poly(A) sequences are located near the 3' end of messenger RNA, and the kinetics of their appearance on messenger RNA precursor indicates that poly(A)(25) is added before poly(A)(100). Dictyostelium nuclear DNA contains 14,000-15,000 sequences of poly(dT)(25) which could code for the smaller poly(A) residues. The poly(A)(100) must be added post-transcriptionally. The poly(dT)(25) sequences are interspersed throughout the genome and may well represent transcription termination regions.
细胞黏菌盘基网柄菌的信使核糖核酸（mRNA）含有两类大致等摩尔量的聚腺苷酸[poly(A)]；一类约25个核苷酸长，另一类约100个核苷酸长。至少一半的信使核糖核酸分子各自含有一个聚腺苷酸（25）序列和一个聚腺苷酸（100）序列；这两个聚腺苷酸序列都位于信使核糖核酸的3'端附近，它们在信使核糖核酸前体上出现的动力学表明聚腺苷酸（25）在聚腺苷酸（100）之前添加。盘基网柄菌核DNA含有14,000 - 15,000个聚脱氧胸苷酸（25）序列，这些序列可能编码较小的聚腺苷酸残基。聚腺苷酸（100）必须在转录后添加。聚脱氧胸苷酸（25）序列散布于整个基因组中，很可能代表转录终止区域。
