REGULATION OF IRON-STRESS-RESPONSE BY WHOLE-PLANT ACTIVITY
REGULATION OF IRON-STRESS-RESPONSE BY WHOLE-PLANT ACTIVITY
复制标题
DOI：
10.1080/01904168409363226
复制
发表时间：
1984-01-01
影响因子：
2.1
通讯作者：
LANDSBERG, EC
中科院分区：
文献类型：
--
作者：
LANDSBERG, EC
对各种铁高效物种的电子显微镜研究表明，响应于铁应力的转移细胞形成是细胞学水平上铁效率的典型特征。有相当多的证据表明，这些细胞的功能特点是生产还原剂和质子挤出，导致铁的吸收和转运增强。它们还可能参与有机酸的产生，这将促进H+流出以及铁的螯合作用以进行长距离运输。此外，木质部薄壁细胞似乎在Fe向输导系统释放的代谢调节中起着重要作用，推测生长最密集的幼叶对Fe的需求量高，向根部发出一个“信号”，诱导传递细胞的形成，从而促进Fe的吸收和转运。战略定位在拍摄中的转移细胞可以调节铁（III）的选择性运输到褪绿的叶子，在那里发生的光化学还原之前，生理纳入。叶绿体中铁蛋白的形成被认为是作为一种缓冲剂，对潜在的有害过量的“游离”铁所造成的大量铁动员的根。
Electron microscopic investigations of various Fe‐efficient species show that transfer cell formation in response to Fe‐stress is a typical feature of Fe‐efficiency at a cytological level. There is considerable evidence that, these cells are functionally characterized by production of reductants and by proton extrusion, leading to enhanced Fe uptake and translocation. They may also be involved in production of organic acids which would facilitate H+‐efflux as well as chelation of Fe for long distance transport. Furthermore, xylem parenchyma cells seem to play a significant role in the metabolic regulation of Fe release to the conducting system.It is supposed that the young, most intensively growing leaves with high Fe demand send a ‘signal’ to the roots which induces transfer cell formation and elevated Fe uptake and translocation. Strategically located transfer cells in the shoot may regulate the selective transport of Fe(III) to the chlorotic leaves where its photochemical reduction occurs prior to physiological incorporation. Ferritin formation in chloroplasts is assumed to act as a buffer against a potentially detrimental overdose of ‘free’ iron resulting from massive Fe mobilization by the roots.