Nozaki T, Haynes P A, Cross G A
Laboratory of Molecular Parasitology, Rockefeller University, New York, NY 10021-6399, USA.
Mol Biochem Parasitol. 1996 Nov 25;82(2):245-55. doi: 10.1016/0166-6851(96)02741-7.
An immunodominant 72-kDa surface glycoprotein (Gp72) of Trypanosoma cruzi is involved in adhesion of the flagellum to the cell body (Cooper, R, Ribeiro de Jesus, A and Cross, G.A.M (1993) J. Cell Biol. 122, 149-156). We have characterized a gene, flagellum-adhesion glycoprotein genel (fla1), from Trypanosoma brucei that encodes a 546 amino-acid protein (Fla1) with high similarity to Gp72. Their sequence similarity and cellular localization suggest that Fla1 and Gp72 have similar functions. We could disrupt individual fla1 alleles but not both, suggesting that fla1 is essential in T. brucei, in contrast to the situation for gp72 in T. cruzi. Using affinity-purified polyclonal antibody, raised against part of the amino-terminal domain of Fla1 expressed in Escherichia coli, we showed that Fla1 is concentrated along the flagellum and in the flagellar pocket in both bloodstream-form and procyclic trypanosomes. Fla1 from both life-cycle stages is N-glycosylated. Fla1 from bloodstream-form T. brucei contains additional glycans, which can be liberated by treatment with mild acid, suggestive of phosphodiester linkages.
克氏锥虫的一种免疫显性72-kDa表面糖蛋白（Gp72）参与鞭毛与细胞体的黏附（库珀，R，里贝罗·德·热苏斯，A和克罗斯，G.A.M（1993年）《细胞生物学杂志》122卷，149 - 156页）。我们鉴定了来自布氏锥虫的一个基因，鞭毛黏附糖蛋白基因1（fla1），它编码一种与Gp72高度相似的含546个氨基酸的蛋白质（Fla1）。它们的序列相似性和细胞定位表明Fla1和Gp72具有相似功能。我们能够破坏单个fla1等位基因，但不能破坏两个，这表明fla1在布氏锥虫中是必需的，这与克氏锥虫中gp72的情况相反。使用针对在大肠杆菌中表达的Fla1氨基末端结构域的一部分制备的亲和纯化多克隆抗体，我们发现Fla1在血流型和前循环型锥虫中都沿着鞭毛和鞭毛囊聚集。来自两个生命周期阶段的Fla1都进行了N-糖基化。来自血流型布氏锥虫的Fla1含有额外的聚糖，用弱酸处理可使其释放，提示存在磷酸二酯键。
