The mechanistic role of METTL14 in UVB-induced skin tumorigenesis

核苷酸切除修复(NER)是去除大量dna损伤的主要dna修复机制。 由UVB辐射以及其他环境致癌物质引起的产品。作为规范的一个子类型 全球基因组NER(GG-NER)修复整个基因组的DNA损伤，是 预防皮肤癌，美国最常见的癌症，以及脑癌和肺癌1-7。 然而，调节GG-NER能力的分子机制仍然知之甚少。最近，我们 发现了METTL14(类甲基转移酶14)的一个新作用，作为N6的关键成分- 甲基腺苷(M6A)RNA甲基转移酶和编写器，促进GG-NER和抑制肿瘤 成长。M6A RNA甲基化是真核生物信使中含量最丰富的内部化学修饰 RNA(信使核糖核酸)以及长非编码RNA(LncRNA)。M6A修饰调控RNA及其受体的命运 功能，如信使核糖核酸的稳定性，核加工，运输，定位，翻译，初级microRNA 加工，以及RNA-蛋白质相互作用。这项提议的目标是确定 METTL14作为M6A的关键编写者，调控GG-NER和UVB诱导的皮肤癌。我们的初步数据 提示METTL14作为一种关键的M6A写入蛋白，在调节GG-NER和皮肤方面起着关键作用 肿瘤发生学。因此，我们假设METTL14作为关键的M6A编写器，在GG-NER和 UVB通过转录后调控其主要靶基因的表达而诱发皮肤癌。 为了验证这一假设，我们将使用几种新的方法，包括转录组范围的m6A图谱， ECLIP-seq和RIP-seq.此外，我们将使用一种新的带有皮肤特异性METTL14缺失的小鼠模型。我们的 假设将在三个具体目标中得到检验。目标1将确定METTL14 调节GG-NER。目标2将确定UVB辐射下调METTL14的机制。 目的3将确定抑制METTL14在UVB诱导的小鼠皮肤肿瘤形成中的后果。 我们建议的项目的成功完成可能会极大地扩大我们对GG-NER监管和 METTL14和m6A RNA甲基化抑制肿瘤，为更好地发展提供新的机遇 通过靶向METTL14途径预防和治疗皮肤癌的策略。癌症更多地出现在皮肤中 比在任何其他器官部位都要多，很可能是因为环境破坏。此外，我们在GG-NER的工作 而METLL14不仅在皮肤癌中有显著意义，而且也适用于其他类型的肿瘤。

Nucleotide excision repair (NER) is the major DNA repair mechanism that removes bulky DNA damage products caused by UVB radiation as well as other environmental carcinogens. As a subtype of canonical NER, global genome NER (GG-NER) repairs DNA damage across the whole genome, and is essential for preventing skin cancer, the most common cancer in the US, as well as cancers in the brain and lungs 1-7. However, the molecular mechanism of regulating GG-NER capacity remains poorly understood. Recently, we discovered a novel role for METTL14 (methyltransferase-like 14), as a key component of the N6- methyladenosine (m6A) RNA methyltransferase and writer, in promoting GG-NER and suppressing tumor growth. m6A RNA methylation is the most abundant internal chemical modification in eukaryotic messenger RNA (mRNA) as well as long non-coding RNA (lncRNA). m6A modification regulates the fate of RNA and its functions, such as mRNA stability, nuclear processing, transport, localization, translation, primary microRNA processing, and RNA-protein interactions. The goal of this proposal is to determine the mechanism by which METTL14, as a key m6A writer, regulates GG-NER and UVB-induced skin cancer. Our preliminary data suggest that METTL14, as a key m6A writer protein, plays a critical role in regulating GG-NER and skin tumorigenesis. Thus we hypothesize that METTL14, as a key m6A writer, plays a critical role in GG-NER and UVB-induced skin cancer through posttranscriptionally regulating the expression of its essential target genes. To test this hypothesis, we will employ several new methods including transcriptome-wide m6A mapping, eCLIP-seq, and RIP-seq. In addition, we will use a new mouse model with skin-specific METTL14 deletion. Our hypothesis will be tested in three Specific Aims. Aim 1 will determine the mechanism by which METTL14 regulates GG-NER. Aim 2 will determine the mechanism by which UVB radiation down-regulates METTL14. Aim 3 will determine the consequences of METTL14 inhibition in UVB-induced skin tumorigenesis in mice. Successful completion of our proposed project may vastly expand our knowledge of GG-NER regulation and tumor suppression by METTL14 and m6A RNA methylation, providing new opportunities for developing better strategies to prevent and treat skin cancer by targeting the METTL14 pathway. Caners arise in the skin more than in any other organ site, most likely due to environmental damage. In addition, our work here in GG-NER and METLL14 is not only significant in skin cancer, but is also applicable to other tumor types as well.