Huang F Z, Weisblat D A
Department of Molecular and Cell Biology, University of California, Berkeley, 94720-3200, USA.
Development. 1996 Jun;122(6):1839-47. doi: 10.1242/dev.122.6.1839.
In embryos of glossiphoniid leeches such as Helobdella triserialis and H. robusta, pairs of adjacent 'o/p' ectodermal blast cells are known to be developmentally equipotent and yet eventually contribute distinct sets of 'O' and 'P' progeny to the nervous system and epidermis of the mature leech. It has been thought that the fate-determining interactions in this 'O-P equivalence group' take place between the equipotent cells themselves. We show here that such intra-group interactions are neither necessary nor sufficient. Instead, transient contact with cells in another ectodermal lineage is necessary and sufficient to induce o/p blast cells to assume the P fate. In the absence of this contact they assume the O fate.
在诸如三带扁蛭和强壮扁蛭等舌蛭科水蛭的胚胎中，已知相邻的成对“o/p”外胚层胚细胞在发育上具有同等潜能，但最终会为成熟水蛭的神经系统和表皮贡献不同的“O”和“P”子代细胞群。人们一直认为，在这个“O - P 等效组”中决定命运的相互作用发生在具有同等潜能的细胞自身之间。我们在此表明，这种组内相互作用既非必要条件也非充分条件。相反，与另一个外胚层谱系中的细胞进行短暂接触对于诱导 o/p 胚细胞呈现 P 命运而言是必要且充分的。在没有这种接触的情况下，它们会呈现 O 命运。
