Lohse Swanhild, Hause Bettina, Hause Gerd, Fester Thomas
Leibniz Institute of Plant Biochemistry, Department of Secondary Metabolism, Weinberg 3, D-06120 Halle (Saale), Germany.
Plant Cell Physiol. 2006 Aug;47(8):1124-34. doi: 10.1093/pcp/pcj083. Epub 2006 Jul 18.
We have analyzed plastid proliferation in root cortical cells of Medicago truncatula colonized by arbuscular mycorrhizal (AM) fungi by concomitantly labeling fungal structures, root plastids, a protein involved in plastid division (FtsZ1) and a protein involved in the biosynthesis of AM-specific apocarotenoids. Antibodies directed against FtsZ1 have been generated after heterologous expression of the respective gene from M. truncatula and characterization of the gene product. Analysis of enzymatic activity and assembly experiments showed similar properties of this protein when compared with the bacterial proteins. Immunocytological experiments allowed two phases of fungal and plastid development to be clearly differentiated and plastid division to be monitored during these phases. In the early phase of arbuscule development, lens-shaped plastids, intermingled with the arbuscular branches, divide frequently. Arbuscule degradation, in contrast, is characterized by large, tubular plastids, decorated by a considerable number of FtsZ division rings.
我们通过同时标记真菌结构、根质体、参与质体分裂的一种蛋白质（FtsZ1）以及参与丛枝菌根（AM）特异性类胡萝卜素生物合成的一种蛋白质，分析了被AM真菌定殖的蒺藜苜蓿根皮层细胞中的质体增殖情况。针对FtsZ1的抗体是在对蒺藜苜蓿相应基因进行异源表达并对基因产物进行表征后产生的。酶活性分析和组装实验表明，与细菌蛋白相比，该蛋白质具有相似的特性。免疫细胞化学实验能够清晰区分真菌和质体发育的两个阶段，并在这些阶段监测质体分裂。在丛枝发育的早期阶段，与丛枝分支交织在一起的透镜状质体频繁分裂。相比之下，丛枝降解的特征是大型管状质体，有相当数量的FtsZ分裂环。
