Transgenic rescue of congenital heart disease and spina bifida in Splotch mice.
Transgenic rescue of congenital heart disease and spina bifida in Splotch mice.
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发表时间：
1999-06
期刊：
影响因子：
4.6
通讯作者：
Jun Li;Kenneth C. Liu;F. Jin;M. Lu;Jonathan A. Epstein
中科院分区：
文献类型：
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作者：
Jun Li;Kenneth C. Liu;F. Jin;M. Lu;Jonathan A. Epstein
Pax3缺陷型Spotch小鼠显示神经管缺陷和一系列神经嵴相关异常，包括心脏流出道缺陷、背根神经节和色素沉着。Pax3在从背神经管出现的神经嵴细胞中表达。Pax3也在体节中表达，神经嵴细胞通过体节迁移，这是轴下肌肉发育所必需的。纯合子突变体Spotch胚胎在胚胎第14天死亡。我们已经利用近端1.6 kb Pax3启动子和上游调控元件的工程转基因小鼠再现内源性Pax3表达的神经管和神经嵴，但不是体节。Pax3在这些组织中的过度表达揭示了没有可辨别的表型。将转基因小鼠繁殖到Spotch背景上证明Pax3的神经管和神经嵴表达足以挽救神经管闭合、心脏发育和其他神经嵴相关缺陷。转基因斑点小鼠存活至出生，在出生时，它们死于呼吸衰竭，继发于缺乏肌肉隔膜。四肢肌肉也没有。这些结果表明，调节元件足以为心脏发育和神经管闭合所需的Pax3的功能性表达内的区域1.6 kb上游的Pax3转录起始位点。此外，用于该转基因的单一Pax3同种型足以执行这些发育过程。虽然细胞外基质和环境的体节通过神经嵴迁移是已知的影响神经嵴的行为，我们的研究结果表明，Pax3缺陷的体节能够支持适当的神经嵴迁移和功能，这表明细胞自主的作用Pax3在神经嵴。
Pax3-deficient Splotch mice display neural tube defects and an array of neural crest related abnormalities including defects in the cardiac outflow tract, dorsal root ganglia and pigmentation. Pax3 is expressed in neural crest cells that emerge from the dorsal neural tube. Pax3 is also expressed in the somites, through which neural crest cells migrate, where it is required for hypaxial muscle development. Homozygous mutant Splotch embryos die by embryonic day 14. We have utilized the proximal 1.6 kb Pax3 promoter and upstream regulatory elements to engineer transgenic mice reproducing endogenous Pax3 expression in neural tube and neural crest, but not the somite. Over expression of Pax3 in these tissues reveals no discernible phenotype. Breeding of transgenic mice onto a Splotch background demonstrates that neural tube and neural crest expression of Pax3 is sufficient to rescue neural tube closure, cardiac development and other neural crest related defects. Transgenic Splotch mice survive until birth at which time they succumb to respiratory failure secondary to absence of a muscular diaphragm. Limb muscles are also absent. These results indicate that regulatory elements sufficient for functional expression of Pax3 required for cardiac development and neural tube closure are contained within the region 1.6 kb upstream of the Pax3 transcriptional start site. In addition, the single Pax3 isoform used for this transgene is sufficient to execute these developmental processes. Although the extracellular matrix and the environment of the somites through which neural crest migrates is known to influence neural crest behavior, our results indicate that Pax3-deficient somites are capable of supporting proper neural crest migration and function suggesting a cell autonomous role for Pax3 in neural crest.