tRNA甲基转移酶NSun2促进细胞生长，与目前公认的衰老相关疾病前列腺癌也密切相关，但其作用靶标与机制尚不清楚。 前期研究结果显示，NSun2通过甲基化关键衰老相关基因CDK1、p27KIP1及c-myc mRNA 的3'-或5'-非翻译区调控这些基因的表达。本课题拟以前期结果为线索，进一步探讨NSun2调控CDK1、p27及c-myc表达的分子机制；探讨NSun2对上述基因的调控对衰老进程及衰老性疾病发生发展的影响。这些研究将初步阐明NSun2调控衰老的分子机制, 为衰老相关疾病的防治提供新的靶标。鉴于mRNA帽子结构外的甲基化及其生物学意义是迄今罕见被涉足的领域，本课题预期成果也必将为基因调控及相关研究提供新的方向。

The tRNA methyltransferase NSun2 acts as a cell growth promoting factor and is closely related to proatate cancer, a well-known aging-related diseases. However, the down-stream effectors regulated by NSun2 and the mechanisms underlying remain unkown. Recently, we have found that NSun2 methylates the 3'- or 5'-UTR of mRNAs encoding CDK1, c-myc, and p27CIP1, thereby regulating the expression of these key senescence-associated genes. Based on these findings, we set out to investigate the mechanisms underlying NSun2-mediated regulation of CDK1, c-myc, and p27CIP1, investigate the impact of NSun2-CDK1, NSun2-p27, and NSun2-cmyc regulatory processes on aging process, and investigate the impact of above regulatory processes on aging-related diseases. These studies will clarify the role of NSun2 in the process of aging,and provide a novel target for the treatment and prevention of aging-related diseases. Given that the methylation of mRNA at positions other than the 5'-cap and its biological impacts remain largely unkown, our studies may also provide a novel direction for gene regulation and related areas.