Inhibition of polarizing activity in the anterior limb bud is regulated by extracellular factors.
Inhibition of polarizing activity in the anterior limb bud is regulated by extracellular factors.
复制标题
前肢芽极化活动的抑制受细胞外因素调节。
DOI：
10.1006/dbio.2001.0500
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Muneoka,K
中科院分区：
文献类型：
--
作者：
Schaller,SA;Muneoka,K
发育中肢体的前后方模式在很大程度上被视为极化活动的函数。然而，最近在多指突变体中的证据表明，正确的模式的发展还需要前肢中的抑制通路的参与，以防止次级极化区的形成，从而限制产生的数字的数量。我们报道了一项新的发现，从小鼠后肢Bud-4细胞系中移植细胞外基质可以从鸡前肢间充质中诱导出额外的指头，包括具有后部表型的指头。与之前描述的肢体发育过程中的模式指定机制不同，研究表明，细胞外基质效应与主动信号的释放无关。相反，有证据表明，细胞外基质移植物中的硫酸乙酰肝素部分结合了参与抑制前极化活动的内源性细胞外因子，导致前肢去抑制，并诱导了包括Sonic Hedgehog和骨形态发生蛋白-2在内的极化区标记基因。
Anterior–posterior patterning of the developing limb is largely viewed as a function of polarizing activity. Recent evidence in polydactylous mutants, however, indicates that development of proper pattern also requires the involvement of inhibitory pathways in the anterior limb that prevent secondary polarizing zone formation, thus limiting the number of digits produced. We report the novel finding that grafts of extracellular matrix from the Mouse Posterior Limb Bud-4 cell line can induce supernumerary digits, including digits with posterior phenotype, from anterior chick limb mesenchyme. Unlike previously described mechanisms of pattern specification during limb development, it is shown that the extracellular matrix effect is not associated with release of an active signal. Rather, evidence is presented suggesting that heparan sulfate moieties in extracellular matrix grafts bind an endogenous, extracellular factor involved in inhibition of anterior polarizing activity, leading to derepression of the anterior limb and induction of polarizing zone marker genes including Sonic hedgehog and Bone morphogenetic protein-2.