Iron modulates phenotypic variation and phosphorylation of P270 in double-stranded RNA virus-infected Trichomonas vaginalis
Iron modulates phenotypic variation and phosphorylation of P270 in double-stranded RNA virus-infected Trichomonas vaginalis
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DOI：
10.1128/iai.67.8.4298-4302.1999
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发表时间：
1999-08-01
影响因子：
3.1
通讯作者：
Alderete, JF
中科院分区：
文献类型：
--
作者：
Alderete, JF
感染双链 RNA 病毒的阴道毛滴虫会根据免疫原性蛋白 P270 的表面表达与细胞质表达而发生表型变异。通过使用 P270 单克隆抗体 (MAb) 进行细胞荧光测定如何产生荧光和非荧光毛滴虫来检查批次培养物。在缺铁培养基中生长的寄生虫中，表面 P270 与 MAb 发生反应的荧光生物的数量和强度明显增加。将铁限制生物体置于补充铁的培养基中会增加非荧光毛滴虫的数量。通过荧光激活细胞分选获得的具有和不具有表面 P270 的纯化毛滴虫亚群在置于高铁和低铁培养基中时分别恢复为非荧光和荧光表型。在病毒阴性阴道毛滴虫分离株或源自病毒感染分离株的病毒阴性子代毛滴虫中，P270 的铁没有明显的类似调节。 MAb 在低铁和高铁培养基中生长的相同数量寄生虫的总蛋白免疫印迹上可检测到等量的 P270。最后，发现 P270 在高铁寄生虫中高度磷酸化。因此，铁在调节携带病毒的寄生虫中 P270 的表面定位方面发挥着作用。
Trichomonas vaginalis infected with a double-stranded RNA virus undergoes phenotypic variation on the basis of surface versus cytoplasmic expression of the immunogenic protein P270. Examination of batch cultures by how cytofluorometry with monoclonal antibody (MAb) to P270 yields both fluorescent and nonfluorescent trichomonads. Greater numbers and intensity of fluorescent organisms with surface P270 reactive with MAb were evident in parasites grown in medium depleted of iron. Placement of iron-limited organisms in medium supplemented with iron gave increased numbers of nonfluorescent trichomonads. Purified subpopulations of trichomonads with and without surface P270 obtained by fluorescence-activated cell sorting reverted to nonfluorescent and fluorescent phenotypes when placed in high- and low-iron media, respectively. No similar regulation by iron of P270 was evident among virus-negative T. vaginalis isolates or virus-negative progeny trichomonads derived from virus-infected isolates. Equal amounts of P270 were detectable by MAb on immunoblots of total proteins from identical numbers of parasites grown in low- and high-iron media. Finally, P270 was found to be highly phosphorylated in high-iron parasites. Iron, therefore, plays a role in modulating surface localization of P270 in virus-harboring parasites.