Abstract:
Growth and development of the Ceratopteris hermaphroditic gametophytes are dependent on cell proliferation in the marginal meristem, which when destroyed will regenerate at a new location on the body margin. We established a laser ablation method to destroy a single initial cell in the meristem. Ablation caused the cessation of cell proliferation accompanied by the disappearance of the expression of an auxin synthesis gene (CrTAA2) and a cell proliferation marker gene (CrWOXB). New meristem regeneration occurred within a predictable distance from the original two days post-ablation, signified by cell proliferation and the expression of CrTAA2. Treatment with the naturally occurring auxin indole-3-acetic acid (IAA), synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D), or the transport inhibitor naphthylphthalamic acid (NPA) altered positioning of the original marginal meristem toward the apex of the gametophyte. IAA altered positioning of the regenerated meristem after damaging the original meristem. A model of auxin involvement in the positioning of the marginal meristem in Ceratopteris is presented to encompass these results.
摘要:
Ceratopteris雌雄同体配子体的生长和发育取决于边缘分生组织中的细胞增殖,当被摧毁时,它将在身体边缘的新位置再生。我们建立了一种激光烧蚀方法来破坏分生组织中的单个初始细胞。消融导致细胞增殖停止,同时生长素合成基因(CrTAA2)和细胞增殖标记基因(CrWOXB)的表达消失。新的分生组织再生发生在距消融后两天的可预测距离内,细胞增殖和CrTAA2的表达。用天然存在的生长素吲哚-3-乙酸(IAA)处理,合成生长素2,4-二氯苯氧基乙酸(2,4-D),或转运抑制剂萘基邻苯二甲酸(NPA)改变了原始边缘分生组织向配子体顶端的定位。IAA在破坏原始分生组织后改变了再生分生组织的定位。提出了生长素参与Ceratopteris边缘分生组织定位的模型,以涵盖这些结果。