Iatrou K, Gedamu L, Dixon G H
Can J Biochem. 1979 Jun;57(6):945-56. doi: 10.1139/o79-115.
Poly(A)+ protamine mRNA (pmRNA) components were isolated after separation on denaturing preparative polyacrylamide gels. The four size classes of protamine mRNA described previously were found to contain poly(A) tracts of different lengths. The pmRNA1 was found to be associated with (A)110, pmRNA2 with (A)90, pmRNA3 with (A)85, and pmRNA4 with (A)69. Following deadenylation with RNase H after duplex formation with oligo-dT, the isolated mRNAs were found to be still heterogeneous, although highly enriched in certain of the deadenylated components. DNA complementary to the isolated mRNAs (cDNA) was synthesized in vitro. Following depurination, the oligopyrimidine maps indicated that C7T4, corresponding to an Arg-Arg-Gly-Gly sequence in protamine and originally thought to be characteristic of all mRNA components, is present in only one or possibly tow of the components. Cross-hybridizations between the cDNAs and the four poly(A)+ pmRNAs indicated that a basic polynucleotide unit of substantial length is common to all four mRNAs and that the existing nucleotide sequence variations probably originate from one or both of the non-coding portions of the mRNA molecules.
在变性制备聚丙烯酰胺凝胶上分离后，分离出了聚腺苷酸加尾精蛋白mRNA（pmRNA）组分。先前描述的四种精蛋白mRNA大小类别被发现含有不同长度的聚腺苷酸序列。发现pmRNA1与（A）110相关联，pmRNA2与（A）90相关联，pmRNA3与（A）85相关联，pmRNA4与（A）69相关联。在用寡聚dT形成双链体后用核糖核酸酶H进行去腺苷酸化处理后，发现分离出的mRNA仍然是异质的，尽管在某些去腺苷酸化组分中高度富集。体外合成了与分离出的mRNA互补的DNA（cDNA）。脱嘌呤后，寡嘧啶图谱表明，对应于精蛋白中精氨酸-精氨酸-甘氨酸-甘氨酸序列且最初被认为是所有mRNA组分特征的C7T4，仅存在于其中一个或可能两个组分中。cDNA与四种聚腺苷酸加尾pmRNA之间的交叉杂交表明，所有四种mRNA都有一个相当长的基本多核苷酸单元，并且现有的核苷酸序列变异可能源于mRNA分子的一个或两个非编码部分。
