玉米根中的细胞分裂素生物合成。

Cytokinin biosynthesis in roots of corn.

机构信息

Department of Botany, University of California, 94720, Berkeley, CA, USA.

出版信息

Planta. 1979 Jan;145(4):315-21. doi: 10.1007/BF00388355.

Abstract

Removal of the quiescent center (QC) from the root apex of maize (Zea mays L., cv. Kelvedon 33) initiates a set of events which culiminate in the regeneration of an intact apex with a newly formed QC. Concomitant with the formation of a new QC is a marked reduction in extractable cytokinins in the tissue of the proximal meristem. Replacing the excised QC with a Dowex (acidic cation-exchange resin) bead affects both root growth and QC regeneration. Root growth is inhibited by "plain" Dowex beads and Dowex beads treated with zeatin; this inhibition is reversed if the beads have been treated with CaCl2 (±zeatin). Dowex beads treated with zeatin delay the formation of a new QC; this effect is the same whether or not the beads also contain CaCl2. The results of this investigation support the notions that cytokinin biosynthesis in roots is a result of activities of both the QC and the proximal meristem, and that cytokinins, at least if supplied exogenously, can play a role in root morphogenesis by delaying the regeneration of the QC.

摘要

去除玉米（Zea mays L.，cv. Kelvedon 33）根尖的静止中心（QC）会引发一系列事件，最终导致新形成的 QC 重建完整的根尖。与新 QC 形成同时发生的是，近基分生组织中可提取细胞分裂素的含量显著减少。用 Dowex（酸性阳离子交换树脂）珠替代切除的 QC 会同时影响根的生长和 QC 的再生。“普通”Dowex 珠和用玉米素处理的 Dowex 珠抑制根的生长；如果珠子用 CaCl2（±玉米素）处理，则抑制作用会逆转。用玉米素处理的 Dowex 珠会延迟新 QC 的形成；无论珠子是否含有 CaCl2，都会产生相同的效果。这项研究的结果支持以下观点：根中的细胞分裂素生物合成是 QC 和近基分生组织活动的结果，并且细胞分裂素（至少如果外源供应）可以通过延迟 QC 的再生在根形态发生中发挥作用。