Distinct effects of ectopic expression of Wnt-1, activin B, and bFGF on gap junctional permeability in 32-cell Xenopus embryos.
Distinct effects of ectopic expression of Wnt-1, activin B, and bFGF on gap junctional permeability in 32-cell Xenopus embryos.
复制标题
Wnt-1、激活素 B 和 bFGF 异位表达对 32 细胞非洲爪蟾胚胎间隙连接通透性的明显影响。
DOI：
10.1016/0012-1606(92)90227-8
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发表时间：
1992
影响因子：
2.7
通讯作者：
Moon,RT
中科院分区：
文献类型：
--
作者：
Olson,DJ;Moon,RT
间隙连接通透性的极性通常存在于32细胞阶段的Xenopus胚胎中，因为背侧细胞比腹侧细胞相对更耦合，如通过转移荧光黄染料所测量的。目前的研究扩展了我们的分析，在这个阶段的间隙连接通透性是否可以调制的分泌因子，以及是否在间隙连接通透性的极性与异位表达的影响，这些分泌因子对随后的发育胚胎的表型。激活素B或Wnt-1，但不是bFGF的异位表达后，在更大比例的32细胞期胚胎中检测到腹侧动物极细胞之间的荧光黄转移。腹侧细胞之间染料转移的发生率增加与发育后期的轴向重复相关。然而，动物和植物半球卵裂球之间的荧光黄转移程度存在差异，这取决于先前是否注射了激活素B或Wnt-1 RNA。这些结果表明，32-cellXenopusembryos腹侧细胞之间的间隙连接通透性增强与随后的缺陷在背腹轴相关，虽然目前没有直接的数据表明间隙连接在建立或维持这一轴的作用。此外，虽然激活素B和bFGF都是中胚层诱导生长因子，但只有激活素B在异位表达后对32细胞胚胎的缝隙连接通透性有影响，这表明对这些因子表达的生理反应存在有趣的差异。
A polarity in gap junctional permeability normally exists in 32-cell stageXenopusembryos, in that dorsal cells are relatively more coupled than ventral cells, as measured by transfer of Lucifer yellow dye. The current study extends our analysis of whether gap junctional permeability at this stage can be modulated by secreted factors, and whether the polarity in gap junctional permeability correlates with the effects of ectopic expression of these secreted factors on the subsequent phenotype of the developing embryo. Following ectopic expression of activin B orWnt-1, but not bFGF, the transfer of Lucifer yellow between ventral animal pole cells is detected in a greater percentage of 32-cell stage embryos. This increased incidence of dye transfer between ventral cells correlates with axial duplications later in development. However, there are differences in the extent of Lucifer yellow transfer between animal and vegetal hemisphere blastomeres which is dependent on whether activin B orWnt-1 RNA had previously been injected. These results suggest that enhanced gap junctional permeability between ventral cells of 32-cellXenopusembryos correlates with subsequent defects in the dorsoventral axis, although there are at present no direct data demonstrating a role for gap junctions in establishment or maintenance of this axis. Moreover, while both activin B and bFGF are mesoderm-inducing growth factors, only activin B has effects on gap junctional permeability in 32-cell embryos following ectopic expression, demonstrating an interesting difference in physiological responses to expression of these factors.