Read Rebecca L, Norbury Chris J
Cancer Research UK Molecular Oncology Laboratory, University of Oxford Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom.
J Cell Biochem. 2002;87(3):258-65. doi: 10.1002/jcb.10300.
Polyadenylation of eukaryotic mRNAs in the nucleus promotes their translation following export to the cytoplasm and is an important determinant of mRNA stability. An additional level of control of gene expression is provided by cytoplasmic polyadenylation, which activates translation of a number of mRNAs important in orchestrating cell cycle events in oocytes. Recent studies indicate that cytoplasmic polyadenylation may be a mechanism of translational activation that is more widespread in eukaryotic cells. Here we discuss the roles of a recently identified family of nucleotidyl transferases (encoded by the cid1 gene family) in cell cycle regulation. To date, this family has been characterised mainly in yeasts, but it is conserved throughout the eukaryotes. Biochemical studies have indicated that a subset of members of this family function as cytoplasmic poly(A) polymerases targeting specific mRNAs for translation. This form of translational control appears to be particularly important for cell cycle regulation following inhibition of DNA synthesis.
真核生物mRNA在细胞核内的多聚腺苷酸化作用可促进其输出到细胞质后进行翻译，并且是mRNA稳定性的重要决定因素。细胞质多聚腺苷酸化为基因表达提供了额外的调控水平，它可激活许多在协调卵母细胞细胞周期事件中起重要作用的mRNA的翻译。最近的研究表明，细胞质多聚腺苷酸化可能是一种在真核细胞中更为广泛存在的翻译激活机制。在此，我们讨论最近鉴定出的一个核苷酸转移酶家族（由cid1基因家族编码）在细胞周期调控中的作用。迄今为止，该家族主要在酵母中得到了表征，但在整个真核生物中都保守存在。生化研究表明，该家族的一部分成员作为细胞质多聚（A）聚合酶发挥作用，靶向特定的mRNA进行翻译。这种形式的翻译控制对于DNA合成受到抑制后的细胞周期调控似乎尤为重要。
