Lobreaux S, Briat J F
Laboratoire de Biologie Moléculaire Végétale, Centre National de la Recherche Scientifique, (Unité de Recherche Associée n. 1178), Université Joseph Fourier, Grenoble, France.
Biochem J. 1991 Mar 1;274 ( Pt 2)(Pt 2):601-6. doi: 10.1042/bj2740601.
Iron concentration and ferritin distribution have been determined in different organs of pea (Pisum sativum) during development under conditions of continuous iron supply from hydroponic cultures. No ferritin was detected in total protein extracts from roots or leaves. However, a transient iron accumulation in the roots, which corresponds to an increase in iron uptake, was observed when young fruits started to develop. Ferritin was detectable in total protein extracts of flowers and pods, and it accumulated in seeds. In seeds, the same relative amount of ferritin was detected in cotyledons and in the embryo axis. In cotyledons, ferritin and iron concentration decrease progressively during the first week of germination. Ferritin in the embryo axis was processed, and disappeared, during germination, within the first 4 days of radicle and epicotyl growth. This degradation of ferritin in vivo was marked by a shortening of a 28 kDa subunit, giving 26.5 and 25 kDa polypeptides, reminiscent of the radical damage occurring in pea seed ferritin during iron exchange in vitro [Laulhere, Laboure & Briat (1989) J. Biol. Chem. 264, 3629-3635]. Developmental control of iron concentration and ferritin distribution in different organs of pea is discussed.
在水培条件下持续供应铁的情况下，测定了豌豆（Pisum sativum）发育过程中不同器官的铁浓度和铁蛋白分布。在根或叶的总蛋白提取物中未检测到铁蛋白。然而，当幼果开始发育时，观察到根中有短暂的铁积累，这与铁吸收的增加相对应。在花和豆荚的总蛋白提取物中可检测到铁蛋白，并且它在种子中积累。在种子中，子叶和胚轴中检测到相同相对量的铁蛋白。在子叶中，铁蛋白和铁浓度在萌发的第一周逐渐降低。在萌发过程中，胚轴中的铁蛋白在胚根和上胚轴生长的前4天内被加工并消失。体内铁蛋白的这种降解的特征是28 kDa亚基缩短，产生26.5和25 kDa的多肽，这让人想起豌豆种子铁蛋白在体外铁交换过程中发生的自由基损伤[Laulhere，Laboure & Briat（1989）J. Biol. Chem. 264, 3629 - 3635]。本文讨论了豌豆不同器官中铁浓度和铁蛋白分布的发育控制。
