Meyer C, Waldkötter K, Sprenger A, Schlösser U G, Luther M, Weiler E W
Lehrstuhl für Pflanzenphysiologie, Ruhr-Universität, Bundesrepublik Deutschland.
Z Naturforsch C J Biosci. 1993 Jul-Aug;48(7-8):595-602. doi: 10.1515/znc-1993-7-812.
The recent identification of the fusicoccin-binding protein (FCBP) in plasma membranes from monocotyledonous and dicotyledonous angiosperms has opened the basis for an elucidation of the toxin's mechanism(s) of action and indicated a widespread occurrence of the FCBP in plants. Results of a detailed taxonomic survey of fusicoccin-binding sites are reported. Binding sites were not found in prokaryotes, animal tissues, fungi and algae including the most direct extant ancestors of the land plants (Coleochaete). From the Psilotales (Psilophytatae) to the monocotyledonous angiosperms, all taxa analyzed possessed high-affinity microsomal fusicoccin-binding sites. A heterogeneous picture emerged for the Bryophyta. Anthoceros crispulus (Anthocerotae), the only hornwort available to study, lacked fusicoccin binding. Within the Hepaticae as well as the Musci, species lacking and species exhibiting toxin binding were found. The binding site thus seems to have emerged very early in the evolution of the land plants. The tissue distribution of fusicoccin-binding sites was studied in Vicia faba L. shoots. All tissues analyzed showed fusicoccin binding, although not to the same extent. On a per-cell basis, guard cells were found to contain, compared to mesophyll cells, a nine-fold higher number of binding sites. Based on cell surface area, the site density is by a factor of 32 higher in guard cells than in mesophyll cells. Tissue specific expression of the binding sites is suggested by these findings.
最近在单子叶和双子叶被子植物的质膜中鉴定出了壳梭孢菌素结合蛋白（FCBP），这为阐明该毒素的作用机制奠定了基础，并表明FCBP在植物中广泛存在。本文报道了对壳梭孢菌素结合位点进行详细分类学调查的结果。在原核生物、动物组织、真菌和藻类（包括陆地植物最直接的现存祖先鞘毛藻）中未发现结合位点。从松叶蕨纲（裸蕨植物门）到单子叶被子植物，所有分析的分类群都具有高亲和力的微粒体壳梭孢菌素结合位点。苔藓植物呈现出一种异质性情况。唯一可用于研究的角苔属植物皱叶角苔缺乏壳梭孢菌素结合。在叶苔纲和藓纲中，既发现了缺乏毒素结合的物种，也发现了表现出毒素结合的物种。因此，结合位点似乎在陆地植物进化的早期就已出现。对蚕豆茎中壳梭孢菌素结合位点的组织分布进行了研究。所有分析的组织都显示出壳梭孢菌素结合，尽管程度不同。以每个细胞为基础，发现保卫细胞与叶肉细胞相比，结合位点数量高九倍。基于细胞表面积，保卫细胞中的位点密度比叶肉细胞高32倍。这些发现表明结合位点具有组织特异性表达。
