Koyama E, Nohno T, Myokai F, Kuroiwa A, Ide H, Taniguchi S, Saito T, Nishijima K, Noji S
Department of Oral and Maxillofacial Surgery I, Okayama University Dental School, Japan.
Prog Clin Biol Res. 1993;383A:51-60.
When a mouse zone of polarizing activity (ZPA) at the posterior margin of the limb bud was grafted at the anterior margin of the chick limb bud, we found that expression of the chick homeobox genes, Chox-4.7 and -4.8, was induced prior to the formation of chick extra digits. The induction was observed in the restricted domain close to both grafted mouse ZPA and the chick apical ectodermal ridge (AER). When the posterior half of the AER was removed, the normal expression was diminished in the posterodistal region. Thus, it is likely that at least two distinct factors, one from the ZPA and the other from the AER, provide positional information to induce cooperatively the sequential expression of the Chox-4 genes.
当将小鼠肢体芽后缘的极化活性区（ZPA）移植到鸡肢体芽的前缘时，我们发现在鸡额外趾形成之前，鸡同源框基因Chox-4.7和-4.8的表达就被诱导了。这种诱导在靠近移植的小鼠ZPA和鸡顶外胚层嵴（AER）的受限区域中观察到。当移除AER的后半部分时，正常表达在远后侧区域减少。因此，很可能至少有两个不同的因子，一个来自ZPA，另一个来自AER，提供位置信息以协同诱导Chox-4基因的顺序表达。
