Hobmayer B, Holstein T W, David C N
Johann Wolfgang Goethe-Universität, Zoologisches Institut, Frankfurt am Main, Germany.
Dev Biol. 1997 Mar 1;183(1):1-8. doi: 10.1006/dbio.1996.8491.
Stimulation of epithelial cell cycling by the neuropeptide head activator was analyzed in Hydra magnipapillata and compared with the action of head activator on bud formation and tentacle formation during head regeneration. The results obtained indicate that head activator treatment stimulates epithelial cell division and induces the formation of more tentacle-specific epithelial cells. The number of additional epithelial cells which undergo mitosis during head activator treatment accounts for the increased number of epithelial cells present in the regenerated tentacles. Therefore, the head activator stimulation of tentacle formation can be explained by the mitogenic action of head activator on tentacle cell precursors. To analyze stimulation of bud formation by head activator, polyps of different developmental age were tested under conditions of long-term treatment, and effects on bud formation were compared with effects on epithelial cell proliferation. Head activator treatment strongly stimulated bud formation, but had no detectable effect on epithelial cell numbers. Bud formation occurs at smaller polyp size as a result of head activator treatment, indicating that head activator significantly interferes with the patterning system in hydra.
在大型乳头水螅中分析了神经肽头部激活因子对上皮细胞周期的刺激作用，并将其与头部激活因子在头部再生过程中对芽形成和触手形成的作用进行了比较。所获得的结果表明，头部激活因子处理可刺激上皮细胞分裂，并诱导形成更多的触手特异性上皮细胞。在头部激活因子处理期间经历有丝分裂的额外上皮细胞数量，解释了再生触手中上皮细胞数量的增加。因此，头部激活因子对触手形成的刺激作用，可以通过其对触手细胞前体的促有丝分裂作用来解释。为了分析头部激活因子对芽形成的刺激作用，在长期处理条件下对不同发育年龄的水螅进行了测试，并将其对芽形成的影响与对上皮细胞增殖的影响进行了比较。头部激活因子处理强烈刺激芽的形成，但对上皮细胞数量没有可检测到的影响。由于头部激活因子处理，芽形成发生在较小的水螅体大小，这表明头部激活因子显著干扰了水螅的模式形成系统。
