Department of Biological Sciences, University of Southern California, Los Angeles, California, United States of America.
PLoS One. 2011;6(7):e22072. doi: 10.1371/journal.pone.0022072. Epub 2011 Jul 11.
Dcc is the key receptor that mediates attractive responses of axonal growth cones to netrins, a family of axon guidance cues used throughout evolution. However, a Dcc homolog has not yet been identified in the chicken genome, raising the possibility that Dcc is not present in avians. Here we show that the closely related family member neogenin may functionally substitute for Dcc in the developing chicken spinal cord. The expression pattern of chicken neogenin in the developing spinal cord is a composite of the distribution patterns of both rodent Dcc and neogenin. Moreover, whereas the loss of mouse neogenin has no effect on the trajectory of commissural axons, removing chicken neogenin by RNA interference results in a phenotype similar to the functional inactivation of Dcc in mouse. Taken together, these data suggest that the chick neogenin is functionally equivalent to rodent Dcc.
Dcc 是关键受体，介导轴突生长锥对 netrins 的吸引反应，netrins 是一个在进化过程中被广泛使用的轴突导向线索家族。然而，鸡基因组中尚未鉴定出 Dcc 同源物，这使得 Dcc 可能不存在于禽类中。在这里，我们表明，密切相关的家族成员 neogenin 可能在发育中的鸡脊髓中替代 Dcc 的功能。鸡 neogenin 在发育中的脊髓中的表达模式是鼠 Dcc 和 neogenin 分布模式的组合。此外，虽然小鼠 neogenin 的缺失对连合轴突的轨迹没有影响，但通过 RNA 干扰去除鸡 neogenin 会导致类似于鼠 Dcc 功能失活的表型。综上所述，这些数据表明，鸡 neogenin 在功能上等同于鼠 Dcc。
