Craniofacial Morphogenesis in Prenatal Alcohol Exposure

酒精是一种强有力的神经毒物，而产前酒精暴露是导致精神残疾的主要原因。一 受影响的人群是神经峰。临床上相关的乙醇水平(20-80 mM)会引起神经隆起(NC) 细胞凋亡。我们过去在该奖项下的工作表明，细胞凋亡是由乙醇刺激的 胞内钙(Ca~(2+))瞬变起源于CPY介导的PLC-IP3激活。海流 奖品显示，钙离子瞬变激活CaMKII，进而破坏转录效应器的稳定 β-连环蛋白，它介导典型的Wnt信号和NC生存。拟议的研究直接扩展了这一点 研究“β-连环蛋白缺失是如何导致神经脊细胞凋亡的？”我们将检验这一假设-- 连环蛋白维持NC细胞的黏附和生存因子Snail2(以前称为Slug)的表达。我们进一步 假设乙醇介导的β-连环蛋白的丢失启动了NC细胞的过早分层并抑制 Snail2，从而激活NC细胞凋亡。AIM 1测试Snail2缺失是否直接启动NC细胞凋亡，因为 它控制着细胞凋亡调节因子BCL2和Bax的表达。AIM 2测试β-连环蛋白在NC中的作用 细胞黏附和β-连环蛋白缺失是否刺激早熟NC分层和细胞凋亡。目标3 将我们的工作扩展到测试急性乙醇暴露是否同样破坏了β-连环素及其转录的稳定性 P-连环蛋白控制细胞命运的其他神经元群体的活性，特别是胎儿和成人的大脑 海马体。最后，我们的ARRA补充剂对乙醇敏感和- 耐药NC识别控制NC存活的β-连环蛋白上游的钙依赖因子。目标4 测试这些候选基因在控制NC对乙基的反应方面的有效性。这项工作是合乎逻辑的 延长目前的裁决期限。我们继续使用我们建立的鸡胚模型，它复制了 包括人类在内的哺乳动物的酒精反应，已经很好地描述了NC的发展，并服从于 基因操纵。β-连环蛋白的失调导致了几种神经病理，提示它可能 也调节酒精在胎儿和成人中的作用。

Alcohol is a potent neurotoxicant and prenatal alcohol exposure is a leading cause of mental disability. One affected population is the neural crest. Clinically relevant ethanoi levels (20-80 mM) cause neural crest (NC) apoptosis. Our past work under this award showed that the apoptosis results from an ethanol-stimulated intracellular calcium (Ca2+) transient originating from the CPy-mediated activation of PLC-IP3. The current award shows that the Ca2+ transient activates CaMKII, which in turn destabilizes the transcriptional effector beta-catenin, which mediates canonical Wnt signaling and NC survival. Proposed studies directly extend this work to ask "How does beta-catenin loss cause neural crest apoptosis?" We will test the hypothesis that beta- catenin maintains NC cell adhesion and expression ofthe survival factor snail2 (formerly slug). We further posit that the ethanol-mediated loss of beta-catenin initiates premature NC cell delamination and suppresses snail2, thus activating NC apoptosis. Aim 1 tests whether snail2 loss directly initiates NC apoptosis because it controls the expression ofthe apoptosis regulators bcl2 and bax. Aim 2 tests the role of beta-catenin in NC cell adhesion and whether beta-catenin loss stimulates precocious NC delamination and apoptosis. Aim 3 extends our work to test if acute ethanoi exposure similarly destabilizes beta-catenin and its transcriptional activity in other neuronal populations in which p-catenin controls cell fate, specifically the fetal brain and adult hippocampus. Finally, our ARRA supplement performs high-throughput RNA-Seq of ethanol-sensitive and - resistant NC to identify calcium-dependent factors upstream of beta-catenin that govern NC survival. Aim 4 tests the efficacy of these candidate genes in controlling NC responses to ethanoi. This work is a logical extension ofthe current award. We continue using our established chick embryo model, which replicates the alcohol responses of mammals including humans, has well-described NC development, and is amenable to genetic manipulation. Beta-Catenin dysregulation contributes to several neuropathologies, suggesting it may also modulate alcohol action in the fetus and the adult.