Department of Reprogramming Science, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
PLoS One. 2012;7(9):e45031. doi: 10.1371/journal.pone.0045031. Epub 2012 Sep 17.
Activation-induced cytidine deminase (Aid), a unique enzyme that deaminates cytosine in DNA, shuttles between the nucleus and the cytoplasm. A recent study proposed a novel function of Aid in active DNA demethylation via deamination of 5-hydroxymethylcytosine, which is converted from 5-methylcytosine by the Ten-eleven translocation (Tet) family of enzymes. In this study, we examined the effect of simultaneous expression of Aid and Tet family proteins on the subcellular localization of each protein. We found that overexpressed Aid is mainly localized in the cytoplasm, whereas Tet1 and Tet2 are localized in the nucleus, and Tet3 is localized in both the cytoplasm and the nucleus. However, nuclear Tet proteins were gradually translocated to the cytoplasm when co-expressed with Aid. We also show that Aid-mediated translocation of Tet proteins is associated with Aid shuttling. Here we propose a possible role for Aid as a regulator of the subcellular localization of Tet family proteins.
激活诱导胞苷脱氨酶（Aid）是一种独特的酶，可使 DNA 中的胞嘧啶脱氨，在核和细胞质之间穿梭。最近的一项研究提出了 Aid 的一个新功能，即通过 Ten-eleven translocation（Tet）家族酶将 5-羟甲基胞嘧啶（由 5-甲基胞嘧啶转化而来）脱氨，从而实现活性 DNA 去甲基化。在这项研究中，我们研究了 Aid 和 Tet 家族蛋白同时表达对每种蛋白亚细胞定位的影响。我们发现，过表达的 Aid 主要定位于细胞质，而 Tet1 和 Tet2 定位于细胞核，Tet3 则定位于细胞质和细胞核。然而，当与 Aid 共表达时，核 Tet 蛋白逐渐被转运到细胞质。我们还表明，Aid 介导的 Tet 蛋白易位与 Aid 穿梭有关。在这里，我们提出 Aid 作为 Tet 家族蛋白亚细胞定位调节剂的可能作用。
