Fish Eric W, Boschen Karen E, Parnell Scott E
Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, United States.
Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, United States; Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, United States; Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC, United States.
Reprod Toxicol. 2024 Dec;130:108729. doi: 10.1016/j.reprotox.2024.108729. Epub 2024 Oct 2.
Alcohol exposure during the gastrulation stage of development can disrupt Sonic hedgehog (Shh) signaling and cause eye, craniofacial, and brain defects. One of the genes that regulates Shh signaling is Efcab7, which encodes a protein that facilitates the actions of Smoothened (Smo), a critical component of the Shh pathway. Previous work from our lab has demonstrated that Efcab7 is differentially expressed between two sub-strains of C57BL/6 mice that differ in their sensitivity to gastrulation-stage alcohol exposure. The more alcohol-sensitive C57BL/6 J mice express lower levels of Efcab7 during gastrulation than do the less alcohol-sensitive C57BL/6NHsd mice. The current study examined whether partial or full Efcab7 deletions render mice more sensitive to gastrulation-stage alcohol exposure and affect the sensitivity to other modulators of Shh signaling that cause craniofacial malformations. Efcab7 dams were mated with Efcab7 sires to produce Efcab7, Efcab7, and Efcab7 fetuses. On gestational day 7 (GD 7), they received either alcohol (two doses of 2.9 g/kg, i.p., given 4 hours apart), the Smo antagonist vismodegib (40 mg/kg, or vehicle, p.o.), the Smo agonist SAG (20 mg/kg) or the appropriate vehicles. GD 17 fetuses were collected and examined for ocular and craniofacial dysmorphology. As compared to Efcab7 fetuses, Efcab7 fetuses exposed to alcohol or vismodegib treatment had more severe ocular and craniofacial malformations. In contrast, Efcab7 fetuses had less severe malformations induced by SAG. These results confirm that Efcab7 can modify responses to Shh agonists and antagonists and further identify Efcab7 as a gene important for the sensitivity to gastrulation-stage alcohol exposure.
在发育的原肠胚形成阶段接触酒精会扰乱音猬因子（Shh）信号传导，并导致眼睛、颅面和脑部缺陷。调节Shh信号传导的基因之一是Efcab7，它编码一种促进平滑蛋白（Smo）发挥作用的蛋白质，Smo是Shh信号通路的关键组成部分。我们实验室之前的研究表明，Efcab7在对原肠胚形成阶段酒精暴露敏感性不同的两个C57BL/6小鼠亚系中差异表达。对酒精更敏感的C57BL/6J小鼠在原肠胚形成阶段表达的Efcab7水平低于对酒精不太敏感的C57BL/6NHsd小鼠。当前的研究检查了Efcab7部分或完全缺失是否会使小鼠对原肠胚形成阶段的酒精暴露更敏感，并影响对其他导致颅面畸形的Shh信号调节因子的敏感性。Efcab7母鼠与Efcab7公鼠交配，以产生Efcab7、Efcab7和Efcab7胎儿。在妊娠第7天（GD 7），它们接受酒精（两剂2.9 g/kg，腹腔注射，间隔4小时给药）、Smo拮抗剂维莫德吉（40 mg/kg，或溶剂，口服）、Smo激动剂SAG（20 mg/kg）或相应的溶剂。收集GD 17的胎儿，并检查眼部和颅面畸形情况。与Efcab7胎儿相比，暴露于酒精或维莫德吉处理的Efcab7胎儿有更严重的眼部和颅面畸形。相比之下，SAG诱导的Efcab7胎儿畸形较轻。这些结果证实Efcab7可以改变对Shh激动剂和拮抗剂的反应，并进一步确定Efcab7是一个对原肠胚形成阶段酒精暴露敏感性很重要的基因。
