近年来,人们对植物中的替代性聚腺苷酸化主题的兴趣激增。聚腺苷酸化复合物与许多发育和应激反应之间的联系是公认的。然而,那些将刺激与聚腺苷酸化复合物的功能联系起来的人还不太了解。为此,必须清楚地描述聚腺苷酸化复合物在植物生长和替代聚腺苷酸化中的作用。还必须了解其他分子过程可能有助于替代聚腺苷酸化的方式。这篇综述讨论了这些问题,重点是揭示mRNA多腺苷酸化可能被调节的机制的实例。讨论了从多腺苷酸化复合物中受影响的突变体的表征中得出的见解,在戏弄因果关系方面,这种特征的局限性也是如此。这些限制鼓励探索超出核心聚腺苷酸化复合物的其他方法。塑造植物转录组的两个这样的过程-转录终止和转座子活性的表观遗传控制-也有助于受调控的poly(A)位点选择。这些受试者定义了“正确的位置”-有助于通过mRNA聚腺苷酸化对基因表达进行广泛控制的分子机制。
Recent years have seen an explosion of interest in the subject of alternative
polyadenylation in plants. Connections between the polyadenylation complex and numerous developmental and stress responses are well-established. However, those that link stimuli with the functioning of the polyadenylation complex are less well understood. To this end, it is imperative to clearly delineate the roles of the
polyadenylation complex in both plant growth AND alternative
polyadenylation. It is also necessary to understand the ways by which other molecular processes may contribute to alternative polyadenylation. This
review discusses these issues, with a focus on instances that reveal mechanisms by which mRNA
polyadenylation may be regulated. Insights from from characterizations of mutants affected in the
polyadenylation complex are discussed, as are the limitations of such characterizations when it comes to teasing out cause and effect. These limitations encourage explorations to other processes that are beyond the core polyadenylation complex. Two such processes that sculpt the plant transcriptome - transcription termination and the epigenetic control of transposon activity - also contribute to regulated poly(A) site choice. These subjects define \"the right places\" - molecular mechanisms that contribute to the wide-ranging control of gene expression via mRNA polyadenylation.