Engrailed-1 misexpression in chick embryos prevents apical ridge formation but preserves segregation of dorsal and ventral ectodermal compartments
Engrailed-1 misexpression in chick embryos prevents apical ridge formation but preserves segregation of dorsal and ventral ectodermal compartments
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DOI：
10.1006/dbio.2000.9659
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发表时间：
2000-06-15
影响因子：
2.7
通讯作者：
Lumsden, A
中科院分区：
文献类型：
--
作者：
Altabef, M;Logan, C;Lumsden, A
利用谱系示踪，我们最近显示背侧和腹侧外胚层隔室沿着两侧的身体在鸡胚。室形成在假定的肢体形成区域，在那里它们定位顶脊，也在假定的肢体间（侧面）。在这里，我们表明，使用一种新的技术相结合的命运映射和原位杂交，腹侧室与Engrailed-1（En-1）域的表达相一致。这一巧合表明，En-I可以维持腹侧区室，并且是顶嵴形成所必需的。为了验证这一假设，我们异位表达En-1通过逆转录病毒转移，然后检查肢体发育和细胞谱系限制在外胚层。En-1的错误表达可以完全阻止正常肢体和通过应用FGF-2在侧腹诱导的异位肢体的形成。在这两种情况下，有没有形态学的迹象，顶端外胚层嵴的形成和脊相关基因的表达是不可检测的。与此形成鲜明对比的是，背侧和腹侧外胚层之间的谱系限制没有改变。因此，En-1参与调节脊的形成，但不隔间的维护。(C)北京大学出版社.
Using lineage tracers, we recently showed dorsal and ventral ectodermal compartments along the sides of the body in chick embryos. The compartments are formed both in presumptive limb-forming regions where they position the apical ridge and also in presumptive interlimb (flank). Here we show, using a novel technique combining fate mapping and in situ hybridisation, that the ventral compartment coincides with the Engrailed-1 (En-1) domain of expression. This coincidence suggests that En-l could maintain the ventral compartment and be necessary for apical ridge formation. To test this hypothesis, we ectopically expressed En-1 via retroviral transfer and then examined limb development and cell lineage restriction in the ectoderm. En-1 misexpression can completely prevent formation of both normal limbs and ectopic limbs induced in the flank by application of FGF-2. In both cases, there are no morphological signs of apical ectodermal ridge formation and expression of ridge-associated genes is undetectable. In striking contrast, the lineage restriction between dorsal and ventral ectoderm is not altered. Therefore, En-1 is involved in the regulation of ridge formation but not compartment maintenance. (C) 2000 Academic Press.