改变Hox3.1表达的边界:证据表明抗脚基因调节
R A Pollock1, G Jay, C J Bieberich
1Jerome H. Holland Laboratory, American Red Cross, Rockville, Maryland 20855.
Cell
|December 11, 1992
概括
在小鼠中改变homeobox基因 (Hox) 表达模式导致前部转变和胃肠道问题. 这表明霍克斯基因可能具有相反的调节作用,其中过度表达和不足表达都会导致类似的发育缺陷.
科学领域:
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 在胚胎发育过程中,Homeobox (Hox) 基因对于建立前后体轴至关重要.
- 霍克斯基因的特定区域表达模式决定了细分标识.
- 了解霍克斯基因功能是解读发育过程和先天性疾病的关键.
研究的目的:
- 研究转基因小鼠前后轴中改变Hox3.1基因表达模式的功能后果.
- 探索改变的霍克斯基因分布和由此产生的胚胎转变之间的关系.
- 确定小鼠发育异常和人类先天性疾病之间的潜在分子联系.
主要方法:
- 通过使用来自Hox1.4.4的调节序列,生成具有改性Hox3.1表达模式的转基因小鼠.
- 对新生转基因小鼠脊椎发育和胃肠组织的分析.
- 转基因小鼠的表型与Hox3.1无突变小鼠的表型的比较.
主要成果:
- 转基因小鼠表现出前脊椎转变,而不是预测的后脊椎转变.
- 在转基因后代中观察到严重的胃肠组织形.
- 转基因小鼠的脊椎转变与Hox3.1无基因突变体中观察到的变化相似.
结论:
- 改变Hox3.1转录的前后分布可能导致前部转变和严重的胃肠道缺陷.
- 在Hox3.1过度表达和零突变之间的表型中,具有悖论的相似性表明Hox基因的反调节机制.
- 这些发现为影响轴骨架和胃肠道系统的某些人类发育障碍的分子基础提供了洞察力.
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