PDF(Pubmed)
Abstract：
Plants are dependent on divisions of stem cells to establish cell lineages required for growth. During embryogenesis, early division products are considered to be stem cells, whereas during post-embryonic development, stem cells are present in meristems at the root and shoot apex. PLETHORA/AINTEGUMENTA-LIKE (PLT/AIL) transcription factors are regulators of post-embryonic meristem function and are required to maintain stem cell pools. Despite the parallels between embryonic and post-embryonic stem cells, the role of PLTs during early embryogenesis has not been thoroughly investigated. Here, we demonstrate that the PLT regulome in the zygote, and apical and basal cells is in strong congruence with that of post-embryonic meristematic cells. We reveal that out of all six PLTs, only PLT2 and PLT4/BABY BOOM (BBM) are expressed in the zygote, and that these two factors are essential for progression of embryogenesis beyond the zygote stage and first divisions. Finally, we show that other PLTs can rescue plt2 bbm defects when expressed from the PLT2 and BBM promoters, establishing upstream regulation as a key factor in early embryogenesis. Our data indicate that generic PLT factors facilitate early embryo development in Arabidopsis by induction of meristematic potential.
摘要：
植物依赖于干细胞的分裂来建立生长所需的细胞系。在胚胎发生期间,早期分裂产物被认为是干细胞，而在胚胎后发育过程中，干细胞存在于根和芽尖的分生组织中。PLETHORA/AINTEGUMENTA样（PLT/AIL）转录因子是胚胎后分生组织功能的调节因子，是维持干细胞库所必需的。尽管胚胎干细胞和胚胎后干细胞有相似之处，PLT在早期胚胎发生过程中的作用尚未得到彻底研究。这里,我们证明了受精卵中的PLT调节组，顶端和基底细胞与胚胎后分生组织细胞高度一致。我们透露，在所有六个PLT中，只有PLT2和PLT4/BABYBOOM（BBM）在受精卵中表达，这两个因素对于超过合子阶段和第一次分裂的胚胎发生进程至关重要。最后,我们表明，当从PLT2和BBM启动子表达时，其他PLT可以挽救plt2bbm缺陷，建立上游调控作为早期胚胎发生的关键因素。我们的数据表明，通用PLT因子通过诱导分生组织潜能促进拟南芥的早期胚胎发育。
