Expression of activated MAP kinase in Xenopus laevis embryos:: Evaluating the roles of FGF and other signaling pathways in early induction and patterning
Expression of activated MAP kinase in Xenopus laevis embryos:: Evaluating the roles of FGF and other signaling pathways in early induction and patterning
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DOI：
10.1006/dbio.2000.9917
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发表时间：
2000-12-01
影响因子：
2.7
通讯作者：
Grainger, RM
中科院分区：
文献类型：
--
作者：
Curran, KL;Grainger, RM
成纤维细胞生长因子信号与胚层的形成和轴向的决定有关。一种针对丝裂原活化蛋白激酶(MAPK)活化形式的抗体被用来监测非洲爪哇早期发育过程中体内的成纤维细胞生长因子信号。通过注射显性负向的成纤维细胞生长因子受体(XFD)RNA，年轻胚胎中MAPK的激活被取消，这表明在这种情况下，MAPK主要由EGF激活。激活的MAPK在桑囊胚期动物和边缘区域发生了从胞质定位到核定位的转变，这与所提出的中胚层能力的开始相吻合。激活的MAPK描绘了胚孔形成之前的背侧边缘区域，并在原肠形成过程中持续在该区域，表明成纤维细胞生长因子信号在背侧中胚层中的早期作用。从原肠发育晚期开始，MAPK在后部神经组织中也被激活。抑制PGE信号并不能阻断后脑基因的表达(HOXB9)或激活MAPK；然而，抑制成纤维细胞生长因子信号确实导致激活的MAPK水平显著降低。这些结果表明，其他受体酪氨酸激酶信号通路参与了后脑神经模式的形成。(C)2000年学术出版社。
FGF signaling has been implicated in germ layer formation and axial determination. An antibody specific for the activated form of mitogen-activated protein kinase ((MAPK) was used to monitor FGF signaling in vivo during early Xenopus development. Activation of MAPK in young embryos is abolished by injection of a dominant negative FGF receptor (XFD) RNA, suggesting that MAPK is activated primarily by EGF in this context. A transition from cytoplasmic to nuclear localization of activated MAPK occurs in morula/blastula stage embryo animal and marginal zones coinciding with the proposed onset of mesodermal competence. Activated MAPK delineates the region of the dorsal marginal zone before blastopore formation and persists in this region during gastrulation, indicating an early role for FGF signaling in dorsal mesoderm. Activated MAPK was also found in posterior neural tissue from late gastrulation onward. Inhibition of PGE signaling does not block posterior neural gene expression (HoxB9) or activation of MAPK; however, inhibition of FGF signaling does cause a statistically significant decrease in the level of activated MAPK. These results point toward the involvement of other receptor tyrosine kinase signaling pathways in posterior neural patterning. (C) 2000 Academic Press.