Head patterning and Hox gene expression in an onychophoran and its implications for the arthropod head problem
Head patterning and Hox gene expression in an onychophoran and its implications for the arthropod head problem
复制标题
DOI：
10.1007/s00427-010-0329-1
复制
发表时间：
2010-09-01
影响因子：
2.4
通讯作者：
Akam, Michael
中科院分区：
文献类型：
--
作者：
Eriksson, Bo Joakim;Tait, Noel N.;Akam, Michael
节肢动物的头部问题已经困扰动物学家超过世纪。成年节肢动物的头部是一个复杂的结构，由不确定数量的节段的修改，融合和迁移造成。相比之下，可能是节肢动物姐妹群的有爪类动物有一个相当简单的头部，包括三个在发育过程中明确定义的部分，并产生了三对专门用于感官和食物捕获/操纵目的的附属物的成年头部。前Hox基因唇，长鼻，Hox 3和变形的表达模式的基础上，我们表明，第三这些onychophoran段，轴承粘液乳头，可以与tritcerebrum，最前面的Hox表达节肢动物段。这意味着无论是onychophoran触角和颌骨来自一个更前，霍克斯自由区对应的proto和utocerebrum的节肢动物。我们的数据提供了分子支持的建议，onychophoran头具有发达的附属物，对应于前面的，显然是无附属物的节肢动物头部的区域。
The arthropod head problem has puzzled zoologists for more than a century. The head of adult arthropods is a complex structure resulting from the modification, fusion and migration of an uncertain number of segments. In contrast, onychophorans, which are the probable sister group to the arthropods, have a rather simple head comprising three segments that are well defined during development, and give rise to the adult head with three pairs of appendages specialised for sensory and food capture/manipulative purposes. Based on the expression pattern of the anterior Hox genes labial, proboscipedia, Hox3 and Deformed, we show that the third of these onychophoran segments, bearing the slime papillae, can be correlated to the tritocerebrum, the most anterior Hox-expressing arthropod segment. This implies that both the onychophoran antennae and jaws are derived from a more anterior, Hox-free region corresponding to the proto and deutocerebrum of arthropods. Our data provide molecular support for the proposal that the onychophoran head possesses a well-developed appendage that corresponds to the anterior, apparently appendage-less region of the arthropod head.