Meinhardt Hans
Max-Planck-Institut für Entwicklungsbiologie, Spemannstr. 35, D-72076 Tübingen, Germany.
Curr Opin Genet Dev. 2004 Aug;14(4):446-54. doi: 10.1016/j.gde.2004.06.012.
Coelenterates including hydra are assumed to be close to the last common ancestor before bilaterality evolved. Models based on local self-enhancement and long-range inhibition account for pattern formation and regeneration along this ancestral axis. The body of a hydra-like ancestor evolved into the brain and heart of higher organisms, accounting for the close relationship of both patterning processes. Bilateria require a long-extended organizing region to pattern their dorsoventral axis. Models reveal the difficulties in the generation of such a stripe-like organizer and account for different mechanisms realized in vertebrates and insects. Common pathways involved in hydra budding and in the formation of appendages in higher organisms suggest a possible link.
包括水螅在内的腔肠动物被认为接近两侧对称进化之前的最后一个共同祖先。基于局部自我增强和长程抑制的模型解释了沿着这个祖先轴的模式形成和再生。类似水螅的祖先的身体演变成了高等生物的大脑和心脏，这解释了这两种模式形成过程的密切关系。两侧对称动物需要一个长延伸的组织区域来构建其背腹轴。模型揭示了产生这样一个条纹状组织者的困难，并解释了在脊椎动物和昆虫中实现的不同机制。水螅出芽和高等生物附肢形成所涉及的共同途径表明了一种可能的联系。
