Laboratoire de Physiologie Végétale, Faculté des Sciences, B.P. 1014, Rabat, Morocco.
Plant Physiol. 1978 Oct;62(4):482-5. doi: 10.1104/pp.62.4.482.
As well as showing the existence, during the first stages of in vitro bud neoformation, of cell populations in a tissue composed of a single cell layer (stem epidermis of Torenia fournieri Lind), some new physiological characteristics of mitosis are defined. Most of the cells which divide during organogenesis synthesize their DNA between 20 and 48 hours of culture. On an epidermal strip (10 x 2.5 millimeters composed of about 5,500 cells) 20% of the original cells enter the S-phase. The first division takes place at the 20-hour stage after the entry into the S-phase of a cell population of about 25 cells. Almost none of the cells of this population divide. The greatest percentage of divisions occurs in cells which synthesize DNA near the 48-hour stage. The relation [Formula: see text] has a value of about 25 at the beginning of cell division (20 hours) and falls to a value of about 1.4 for cells which synthesize DNA near the 48-hour stage. A hypothesis of the existence of a mitotic stimulant in the epidermis is put forward; this stimulant, at first weak, increases progressively.
除了显示在体外芽新形成的最初阶段，细胞群体存在于由单个细胞层组成的组织中（Torenia fournieri Lind 的茎表皮），还定义了有丝分裂的一些新的生理特征。在器官发生过程中分裂的大多数细胞在培养的 20 到 48 小时之间合成其 DNA。在一个表皮带（由约 5500 个细胞组成的 10 x 2.5 毫米）中，原始细胞的 20%进入 S 期。第一次分裂发生在进入 S 期后 20 小时，大约 25 个细胞的细胞群体进入 S 期。这个群体中的几乎没有细胞分裂。在接近 48 小时阶段合成 DNA 的细胞中发生的分裂比例最大。在细胞分裂开始时（20 小时），[公式：见文本]的值约为 25，而接近 48 小时阶段合成 DNA 的细胞的值约为 1.4。提出了表皮中存在有丝分裂刺激物的假说；这种刺激物起初较弱，逐渐增强。
