The Role of Ets1 in Melanocyte Development

描述(申请人提供)：黑素细胞来自多能神经脊(NC)细胞，它起源于神经管的背侧。尽管NC细胞最初是多能性的，但它们的分化潜力逐渐受到内在因素和迁移过程中遇到的提示的限制。通过对小鼠色素突变的研究，已经确定了几个与黑素细胞的特性有关的基因。转录因子Pax3、Sox10和MITF的突变导致小鼠和人类的色素减退表型。最近，转录因子Ets1的缺失被证明是由于NC细胞发育不当而导致的心脏畸形。此外，Ets1缺失和杂合子小鼠表现出腹侧色素减少，暗示该转录因子参与了黑素细胞从NC开始的发育。Ets1是一种广泛表达的螺旋-转角-螺旋转录因子，它识别核苷酸序列GGAA/T，在小鼠胚胎的各种发育器官和组织中都有表达，包括NC。Ets1参与了多种过程，包括细胞增殖、凋亡、分化、淋巴样细胞发育、血管生成和侵袭性。这项拟议研究的主要目标是确定Ets1在黑素细胞发育中所起的作用。我们将(1)确定Ets1在黑素细胞系发育过程中的时间需求和作用机制。(2)确定Ets1和黑素细胞基因之间的遗传和分子相互作用。为了实现这些目标，我们将使用体内和体外增殖、凋亡和迁移检测相结合的方法。此外，我们还将进行遗传杂交、启动子分析和结合分析，以评估Ets1与Sox10、Pax3和MITF的相互作用。我们的结果有可能揭示Ets1的新角色，并建立控制黑素细胞发育的转录网络的更完整图景。除了它们与理解细胞谱系规范的基本原则相关外，我们的研究也将与理解涉及NC和皮肤色素沉着的发育障碍相关。 公共卫生相关性：神经脊细胞可产生多种类型的细胞，这些细胞的异常发育可导致几种先天性疾病，包括感觉神经性耳聋、颅面畸形、心脏畸形、甲状腺和舌头受损以及色素沉着障碍。对转录因子Ets1在神经脊细胞和黑素细胞中所起作用的表征将有助于进一步描绘这些疾病背后的根本错误，并可能有助于靶向治疗的发展。

DESCRIPTION (provided by applicant): Melanocytes are derived from pluripotent neural crest (NC) cells, which arise from the dorsal aspect of the neural tube. Although NC cells are initially pluripotent, their differentiation potential gradually becomes restricted depending on intrinsic factors and cues they encounter during their migration. Several genes have been identified that are involved in the specification of melanocytes from the NC through the study of mouse pigmentation mutants. Mutations in the transcription factors Pax3, Sox10, and Mitf result in hypopigmentation phenotypes in mice and humans. Recently, the deletion of the transcription factor Ets1 was shown to produce cardiac malformations as a result of improper NC cell development. Furthermore, Ets1 null and heterozygous mice exhibit ventral hypopigmentation, hinting to the involvement of this transcription factor in melanocyte development from the NC. Ets1 is a widely expressed helix-turn-helix transcription factor which recognizes the nucleotide sequence GGAA/T. It is expressed in various developing organs and tissues in the mouse embryo, including the NC. Ets1 has been implicated in diverse processes, including cell proliferation, apoptosis, differentiation, lymphoid cell development, angiogenesis, and invasiveness. The main goal of the proposed study is to characterize the role played by Ets1 in melanocyte development. We will (1) Determine the temporal requirement and mechanism of action of Ets1 in the development of the melanocyte lineage. (2) Identify genetic and molecular interactions between Ets1 and melanocytic genes. To accomplish these aims we will use a combination of in vivo and in vitro proliferation, apoptosis and migration assays. Additionally, we will perform genetic crosses, promoter analysis and binding assays to evaluate the interaction of Ets1 with Sox10, Pax3, and Mitf. Our results have the potential to uncover a new role for Ets1 and establish a more complete picture of the transcriptional network that controls melanocyte development. Besides their relevance for understanding fundamental principles of cell lineage specification, our studies will also be relevant for the understanding of developmental disorders involving the NC and skin pigmentation. PUBLIC HEALTH RELEVANCE: Neural crest cells give rise to a variety of cell types and the abnormal development of these cells can result in several congenital conditions including sensorineural deafness, cranio-facial abnormalities, cardiac malformations, impaired thyroid and tongue, and pigmentation disorders. The characterization of the role played by the transcription factor Ets1 in neural crest cells and melanocytes will help further delineate the fundamental errors that underlie some of these disorders and possibly contribute to the development of targeted therapies.