Characterizing LIN-12/Notch Regulation and Activity

秀丽隐杆线虫的生活史包含一种称为达尔的发育停滞状态，这种状态发生在 对不利环境条件的反应。这个Dauer阶段是细胞长时间静止期 这不仅与外阴前体细胞的维护有关，而且与外阴前体细胞的重新编程有关。 变成了一种多能状态。通常在开发中，VPC命运规范需要LIN-12/Notch，一口井- 保守的跨膜受体和转录激活因子，用于靶基因的转录激活 来定义未来的细胞身份。然而，在Dauer过程中，这种转录激活被阻止，即使在 存在稳定和激活的LIN-12/Notch。而且，已经经历了细胞命运的VPC 当Dauer进入时，LIN-12/Notch的规范被去区分为多能状态。这个街区是 胰岛素/胰岛素生长因子信号转导，作为其效应因子，转录因子DAF- 16/FoxO，导致部分阻断解除。研究DAUER VPC如何预防LIN-12/Notch 信号，我将研究LIN-12/Notch激活复合体的DNA结合组件Lag-1是如何 在DAUER VPC中调节，我将测试表达稳定和功能的LAG-1是否会缓解DAUER 阻止。我还将进行封闭和非封闭之间的差异基因表达分析实验 Dauer VPC寻找可能对保持VPC处于静态和 多能状态。

The life cycle of Caenorhabditis elegans contains a developmentally arrested state called dauer that occurs in response to adverse environmental conditions. This dauer stage is a period of prolonged cellular quiescence that is associated with not only the maintenance but also reprogramming of the Vulval Precursor Cells (VPCs) into a multipotent state. Normally in development, VPC fate specification requires LIN-12/Notch, a well- conserved transmembrane receptor and transcriptional activator, for transcriptional activation of target genes to define the future cell identity. However, during dauer, this transcriptional activation is blocked, even in the presence of a stable and activated LIN-12/Notch. Moreover, VPCs that had already undergone cell fate specification by LIN-12/Notch are de-differentiated into a multipotent state upon dauer entry. This block is mediated by Insulin/Insulin Growth Factor Signaling, as loss of its effector, the transcriptional factor DAF- 16/FoxO, results in a partial relief of the block. To study how dauer VPCs are able to prevent LIN-12/Notch signaling, I will investigate how LAG-1, the DNA-binding component of the LIN-12/Notch activation complex, is regulated in dauer VPCs, and I will test whether expressing stable and functional LAG-1 will relieve the dauer block. I will also perform a differential gene expression analysis experiment between blocked and unblocked dauer VPCs to look for candidates that may prove essential for maintaining VPCs in a quiescent and multipotent state.