植物细胞中含有类角蛋白多肽及角蛋白cDNA的同源序列

根据中间纤维对去圬剂和高盐溶液的抗性,用类似动物细胞中间纤维抽提的方法,对玉米和烟草的叶肉细胞进行选择性抽提处理,提取中间纤维的蛋白成份。蛋白经SDS聚丙烯酰胺凝胶电泳后,用动物细胞角蛋白的单克隆抗体进行免疫印迹反应,主要显示了分子量为52kD和64kD两种多肽成份。同时,提取玉米和烟草的DNA与α-~(32)P标记的兔K_3cDNA片段RB_3进行点杂交,均呈现较强的阳性反应,说明它们的基因组DNA中存在角蛋白基因的同源序列。

THE KERATIN-LIKE POLYPEPTIDES AND KERATIN cDNA HOMOLOGY SEQUENCE EXIST IN PLANT CELLS

According to the resistence of intermediate filament to detergent and salt solution we prepared the intermediate filament proteins from maize and tobacco mesophyll cells using sequential extraction. The proteins were separated on SDS-PAGE and immuno-blotted to monoclonal anti-keratin antibody. Two major bands at 52 kD and 64 kD were showed in the blotting. Meanwhile, genomic DNA of tobacco and maize dot-hybridized with rabbit K 3 eDNA fragment RB 3. The result indicated that there was keratin cDNA homology sequence in plant genome.