Tomita Kozo, Liu Yining
Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan.
Front Genet. 2018 Aug 3;9:305. doi: 10.3389/fgene.2018.00305. eCollection 2018.
Bicoid interacting 3 domain containing RNA methyltransferase (BCDIN3D) is a member of the Bin3 methyltransferase family and is evolutionary conserved from worm to human. BCDIN3D is overexpressed in breast cancer, which is associated with poor prognosis of breast cancers. However, the biological functions and properties of BCDIN3D have been enigmatic. Recent studies have revealed that human BCDIN3D monomethylates 5'-monophsosphate of cytoplasmic tRNA and . BCDIN3D recognizes the unique and exceptional structural features of cytoplasmic tRNA and discriminates tRNA from other cytoplasmic tRNA species. Thus, BCDIN3D is a tRNA-specific 5'-monophosphate methyltransferase. Methylation of the 5'-phosphate group of tRNA does not significantly affect tRNA aminoacylation by histidyl-tRNA synthetase nor the steady state level or stability of tRNA. Hence, methylation of the 5'-phosphate group of tRNA by BCDIN3D or tRNA itself may be involved in certain unknown biological processes, beyond protein synthesis. This review discusses recent reports on BCDIN3D and the possible association between 5'-phosphate monomethylation of tRNA and the tumorigenic phenotype of breast cancer.
含双尾蚴交互3结构域的RNA甲基转移酶（BCDIN3D）是Bin3甲基转移酶家族的成员，从线虫到人类都具有进化保守性。BCDIN3D在乳腺癌中过表达，这与乳腺癌的不良预后相关。然而，BCDIN3D的生物学功能和特性一直是个谜。最近的研究表明，人BCDIN3D可使细胞质tRNA的5'-单磷酸发生单甲基化，并且BCDIN3D识别细胞质tRNA独特且特殊的结构特征，将其与其他细胞质tRNA种类区分开来。因此，BCDIN3D是一种tRNA特异性的5'-单磷酸甲基转移酶。tRNA的5'-磷酸基团甲基化不会显著影响组氨酰-tRNA合成酶对tRNA的氨酰化作用，也不会影响tRNA的稳态水平或稳定性。因此，BCDIN3D或tRNA自身对tRNA的5'-磷酸基团进行甲基化可能参与了某些未知的生物学过程，而不仅仅是蛋白质合成。这篇综述讨论了关于BCDIN3D的最新报道以及tRNA的5'-磷酸单甲基化与乳腺癌致瘤表型之间可能的关联。
