Identifying non-histone targets of the neural crest methyltransferase NSD3

描述（由申请人提供）：神经嵴细胞是脊椎动物多能细胞的一个群体，它们可以长距离迁移，形成一系列令人印象深刻的细胞类型，并且在各种颅面异常中存在缺陷。产前补充叶酸，甲基化周期中的辅助因子，可以减少颅面出生缺陷的发生率，但直到最近甲基化对神经嵴发育的任何机制影响尚不清楚。Gammill实验室最近的数据表明，赖氨酸甲基转移酶NSD3是神经嵴细胞迁移所必需的。基于迁移神经嵴细胞中NSD3和赖氨酸甲基化蛋白的细胞质定位，以及越来越多的“组蛋白”甲基化转移酶甲基化多种非组蛋白的认识，本研究假设NSD3催化的非组蛋白甲基化调节神经嵴细胞迁移。为了研究这种可能性，目的是通过在定向和开放式框架中通过两种独立、互补的方法识别NSD3的非组蛋白靶点，确定NSD3介导的非组蛋白甲基化在小鸡神经嵴迁移过程中的重要性。这一目标将通过以下方式实现：(1)使用由候选人建立的体外甲基转移酶试验筛选nsd3催化的候选靶点和排列蛋白的甲基化；(2)使用蛋白质组学分析C8161黑色素瘤细胞中nsd3依赖性非组蛋白甲基化；(3)利用鸡瞬态遗传方法确定神经嵴迁移过程中NSD3靶点甲基化的需求。实现这些目标将在NSD3非组蛋白甲基化和神经嵴细胞迁移之间建立直接的功能联系，并将为探索治疗侵袭性癌症和预防出生缺陷开辟令人兴奋的新途径。此外，在完成本项目后，候选人将获得蛋白质组学、生物化学和发育生物学方面的多种专业知识，为其提供广泛的知识基础和坚实的研究基础。在这些领域具有丰富经验的赞助者和共同赞助者的指导将确保研究计划的成功完成，并实施个性化的培训计划，旨在为候选人的成功科学事业做好准备。

DESCRIPTION (provided by applicant): Neural crest cells are a population of vertebrate multipotent cells that migrate over long distances, form an impressive array of cell types, and are defective in diverse craniofacial abnormalities. Prenatal supplementation with folate, a cofactor in the methylation cycle, can reduce the incidence of craniofacial birth defects, yet unti recently any mechanistic impact of methylation on neural crest development was unknown. Recent data in the Gammill lab shows that the lysine methyltransferase NSD3 is required for neural crest cell migration. Based upon the cytoplasmic localization of both NSD3 and lysine methylated proteins in migratory neural crest cells, as well as increasing appreciation that 'histone' methyltransfserases methylate diverse non- histone proteins, this proposal postulates that NSD3-catalyzed methylation of non-histone proteins regulates neural crest cell migration. To investigate this possibility, the objective is to determine the importance of NSD3- mediated non-histone protein methylation during chick neural crest migration by identifying non-histone targets of NSD3 through two independent, complementary approaches in both directed and open-ended frameworks. This objective will be attained by: (1) screening NSD3-catalyzed methylation of candidate targets and arrayed proteins using an in vitro methyltranferase assay established by the candidate, (2) profiling NSD3-dependent non-histone protein methylation in C8161 melanoma cells using proteomics; and (3) determining the requirement for NSD3 target methylation during neural crest migration in vivo using chick transient genetic approaches. Achieving these aims will create a direct functional link between NSD3 non-histone methylation and neural crest cell migration, and will open exciting new avenues to explore in the treatment of aggressive cancers and the prevention of birth defects. Moreover, in completing this project, the candidate will acquire diverse expertise in proteomics, biochemistry, and developmental biology, giving him a broad knowledge base and a strong foundation in research. Mentoring by both a Sponsor and Co-Sponsor with extensive experience in these areas will ensure a successful completion of the research plan, as well as the implementation of a personalized training plan designed to prepare the candidate for a successful scientific career.