Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, USA.
Dev Dyn. 2011 May;240(5):1087-99. doi: 10.1002/dvdy.22629. Epub 2011 Apr 4.
The development of the tetrapod limb during skeletogenesis follows a highly conservative pattern characterized by a general proximo-distal progression in the establishment of skeletal elements and a postaxial polarity in digit development. Salamanders represent the only exception to this pattern and display an early establishment of distal autopodial structures, specifically the basale commune, an amalgamation of distal carpal and tarsal 1 and 2, and a distinct preaxial polarity in digit development. This deviance from the conserved tetrapod pattern has resulted in a number of hypotheses to explain its developmental basis and evolutionary history. Here we summarize the current knowledge of salamander limb development under consideration of the fossil record to provide a deep time perspective of this evolutionary pathway and highlight what data will be needed in the future to gain a better understanding of salamander limb development specifically and tetrapod limb development and evolution more broadly.
在骨骼发生过程中，四足动物肢体的发育遵循一个高度保守的模式，其特征是骨骼元素的建立具有一般的近-远进展，以及指（趾）发育的后轴极性。蝾螈是这种模式的唯一例外，它们表现出远端附肢结构的早期建立，特别是basale commune，这是远端腕骨和跗骨 1 和 2 的融合，以及指（趾）发育中的明显前轴极性。这种偏离保守的四足动物模式导致了许多假说来解释其发育基础和进化历史。在这里，我们总结了当前对蝾螈肢体发育的认识，考虑到化石记录，为这条进化途径提供了一个深远的时间视角，并强调了未来需要哪些数据来更好地理解蝾螈肢体发育，更广泛地说，理解四足动物肢体的发育和进化。
