• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Evidence for the prepattern/cooption model of vertebrate jaw evolution
【24h】

Evidence for the prepattern/cooption model of vertebrate jaw evolution

机译：脊椎动物颌骨进化的模式/选择模型的证据

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The appearance of jaws was a turning point in vertebrate evolution because it allowed primitive vertebrates to capture and process large, motile prey. The vertebrate jaw consists of separate dorsal and ventral skeletal elements connected by a joint. How this structure evolved from the unjointed gill bar of a jawless ancestor is an unresolved question in vertebrate evolution. To understand the developmental bases of this evolutionary transition, we examined the expression of 12 genes involved in vertebrate pharyngeal patterning in the modem jawless fish lamprey. We find nested expression of Dlx genes, as well as combinatorial expression of Msx, Hand and Gsc genes along the dorso-ventral (DV) axis of the lamprey pharynx, indicating gnathostome-type pharyngeal patterning evolved before the appearance of the jaw. In addition, we find that Bapx and Gdf5/6/7, key regulators of joint formation in gnathos-tomes, are not expressed in the lamprey first arch, whereas Barx, which is absent from the intermediate first arch in gnathostomes, marks this domain in lamprey. Taken together, these data support a new scenario for jaw evolution in which incorporation of Bapx and Gdf5/6/7 into a preexisting DV patterning program drove the evolution of the jaw by altering the identity of intermediate first-arch chondrocytes. We present this "Pre-pattern/Cooption" model as an alternative to current models linking the evolution of the jaw to the de novo appearance of sophisticated pharyngeal DV patterning.
机译：颌骨的出现是脊椎动物进化的转折点，因为它使原始脊椎动物能够捕获并处理大型活动性猎物。脊椎动物的颌骨由通过关节连接的独立的背侧和腹侧骨骼元素组成。这种结构如何从无颚祖先的无节g条演变而来，这是脊椎动物进化中尚未解决的问题。为了了解这种进化过渡的发展基础，我们检查了在现代无颚鱼七lamp鳗中涉及脊椎动物咽部模式的12个基因的表达。我们发现七l嘴咽的背腹（DV）轴的Dlx基因的嵌套表达，以及M​​sx，Hand和Gsc基因的组合表达，表明在下颌出现之前进化了gnathostome型咽部形态。此外，我们发现，七角雀科第一个足弓中未表达Bapx和Gdf5 / 6/7，它们是食人鱼-趾关节形成的关键调节器，而鹰嘴豆科的中间第一首弓中缺少的巴克斯标志着这一区域。在南lamp。综上所述，这些数据为颌骨进化提供了一种新的方案，其中将Bapx和Gdf5 / 6/7整合到预先存在的DV图案化程序中，通过改变中间第一弓形软骨细胞的身份来推动颌骨的进化。我们提出此“前模式/共选项”模型，作为当前模型的替代方案，该模型将颌骨的演变与复杂的咽部DV模式的从头出现联系起来。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号