Pearse R V, Tabin C J
Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
J Exp Zool. 1998 Dec 15;282(6):677-90.
Signals that instruct the developing limb bud mesenchyme to form the appropriate elements along the anterior posterior axis emanate from the zone of polarizing activity (ZPA). Studies of the last five years have illustrated that the Sonic hedgehog (Shh) protein mediates the activities of the ZPA. This review will focus on three aspects of the ZPA biology. We will address induction of the ZPA in terms of the factors required for activation and maintenance of Shh expression in the posterior limb bud mesenchyme and the evidence for negative regulatory mechanisms that prevent inappropriate Shh expression. Second, we will discuss the current understanding of Shh processing and transduction of the Shh signal, inferring much from the elegant studies on Drosophila Hedgehog (Hh) protein. Finally, we will address the interpretation of the secreted Shh signal by the limb bud mesenchyme that leads to a predictable morphological response.
引导发育中的肢芽间充质沿前后轴形成适当结构的信号，源自极化活性区（ZPA）。过去五年的研究表明，音猬因子（Shh）蛋白介导了ZPA的活性。本综述将聚焦于ZPA生物学的三个方面。我们将从激活和维持后肢芽间充质中Shh表达所需的因子以及防止Shh异常表达的负调控机制的证据方面，探讨ZPA 的诱导。其次，我们将讨论目前对Shh加工和Shh信号转导的理解，这很大程度上是从对果蝇刺猬因子（Hh）蛋白的精细研究中推断出来的。最后，我们将探讨肢芽间充质对分泌的Shh信号的解读，这会导致可预测的形态学反应。
