MacDonald M H, Mogen B D, Hunt A G
Department of Agronomy, University of Kentucky, Lexington 40546-00914.
Nucleic Acids Res. 1991 Oct 25;19(20):5575-81. doi: 10.1093/nar/19.20.5575.
We have characterized the polyadenylation signal from the octopine synthase (ocs) gene. This signal directs mRNA 3' end formation at a number of distinct sites. A combination of deletion and linker-substitution analyses revealed that each of these sites is controlled by multiple upstream sequence elements. Upstream sequences relatively far (greater than 80 nt) from the ocs poly[A] sites were found to be needed for functioning of these sites. Upstream sequences nearer to poly [A] sites were also found to be involved in mRNA 3' end formation in the ocs gene. In addition, a set of novel elements that mediates 3' end choice was uncovered by deletion analysis of sequences downstream from the ocs polyadenylation sites. Our experiments indicate mRNA 3' end formation in the ocs is controlled by a complex series of cis-acting signals, and suggest that the process of mRNA 3' end formation might be linked to transcription termination.
我们已经对胭脂碱合成酶（ocs）基因的聚腺苷酸化信号进行了特征分析。该信号可在多个不同位点指导mRNA 3'末端的形成。缺失分析和接头替换分析相结合表明，这些位点中的每一个都受多个上游序列元件的控制。发现ocs聚腺苷酸化位点相对较远（大于80个核苷酸）的上游序列对于这些位点的功能是必需的。还发现靠近聚腺苷酸化位点的上游序列参与ocs基因中mRNA 3'末端的形成。此外，通过对ocs聚腺苷酸化位点下游序列的缺失分析，发现了一组介导3'末端选择的新元件。我们的实验表明，ocs基因中mRNA 3'末端的形成受一系列复杂的顺式作用信号控制，并表明mRNA 3'末端的形成过程可能与转录终止有关。
