胚胎中期急性乙醇暴露对 BXD 小鼠神经管细胞死亡数量的遗传影响。

Genetic Influences on the Amount of Cell Death in the Neural Tube of BXD Mice Exposed to Acute Ethanol at Midgestation.

机构信息

Centre for Molecular Medicine and Therapeutics , British Columbia Children's Research Institution, University of British Columbia, Vancouver, British Columbia, Canada.

Department of Anatomy and Neurobiology , University of Tennessee Health Science Center, Memphis, Tennessee.

出版信息

Alcohol Clin Exp Res. 2019 Mar;43(3):439-452. doi: 10.1111/acer.13947. Epub 2019 Feb 12.

DOI:10.1111/acer.13947

PMID:30589433

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6410727/

Abstract

BACKGROUND

Fetal alcohol spectrum disorders (FASD) have a strong genetic component although the genes that underlie this are only beginning to be elucidated. In the present study, one of the most common phenotypes of FASD, cell death within the early developing neural tube, was examined across a genetic reference population in a reverse genetics paradigm with the goal of identifying genetic loci that could influence ethanol (EtOH)-induced apoptosis in the early developing neural tube.

METHODS

BXD recombinant inbred mice as well as the parental strains were used to evaluate genetic differences in EtOH-induced cell death after exposure on embryonic day 9.5. Dams were given either 5.8 g/kg EtOH or isocaloric maltose-dextrin in 2 doses via intragastric gavage. Embryos were collected 7 hours after the initial exposure and cell death evaluated via TUNEL staining in the brainstem and forebrain. Genetic loci were evaluated using quantitative trait locus (QTL) analysis at GeneNetwork.org.

RESULTS

Significant strain differences were observed in the levels of EtOH-induced cell death that were due to genetic effects and not confounding variables such as differences in developmental maturity or cell death kinetics. Comparisons between the 2 regions of the developing neural tube showed little genetic correlation with the QTL maps exhibiting no overlap. Significant QTLs were found on murine mid-chromosome 4 and mid-chromosome 14 only in the brainstem. Within these chromosomal loci, a number of interesting candidate genes were identified that could mediate this differential sensitivity including Nfia (nuclear factor I/A) and Otx2 (orthodenticle homeobox 2).

CONCLUSIONS

These studies demonstrate that the levels of EtOH-induced cell death occur in strain- and region-dependent manners. Novel QTLs on mouse Chr4 and Chr14 were identified that modulate the differential sensitivity to EtOH-induced apoptosis in the embryonic brainstem. The genes underlying these QTLs could identify novel molecular pathways that are critical in this phenotype.

摘要

背景

胎儿酒精谱系障碍（FASD）具有很强的遗传成分，尽管导致这种障碍的基因才刚刚开始被阐明。在本研究中，我们以一种反向遗传学的范式，在遗传参考人群中研究了 FASD 的一种最常见表型，即早期发育神经管内的细胞死亡，目的是确定可能影响早期发育神经管内乙醇（EtOH）诱导细胞凋亡的遗传基因座。

方法

使用 BXD 重组近交系小鼠以及亲本品系来评估胚胎第 9.5 天暴露于 EtOH 后诱导的细胞死亡的遗传差异。通过胃内灌胃给予母体 5.8g/kg EtOH 或等热量麦芽糊精 2 次。在初次暴露后 7 小时收集胚胎，并通过 TUNEL 染色在脑干和前脑评估细胞死亡。在 GeneNetwork.org 上使用数量性状基因座（QTL）分析评估遗传基因座。

结果

在 EtOH 诱导的细胞死亡水平上观察到显著的品系差异，这些差异归因于遗传效应，而不是发育成熟度或细胞死亡动力学等混杂变量。对发育中神经管的两个区域进行比较，发现 QTL 图谱之间遗传相关性很小，没有重叠。仅在脑干中发现了位于鼠染色体 4 中部和染色体 14 中部的显著 QTL。在这些染色体基因座内，鉴定出了许多有趣的候选基因，它们可能介导这种差异敏感性，包括 Nfia（核因子 I/A）和 Otx2（同源异型盒 2）。