Weidner E
J Cell Biol. 1982 Jun;93(3):976-9. doi: 10.1083/jcb.93.3.976.
The polar filaments within microsporidian spores discharges as tubes with subsecond velocity. Populations of discharging tubes of Glugea hertwigi spores pulse-labeled with latex particles for 1-3 s were consistently devoid of label at the distal ends; discharging tubes were completely labeled after 30- to 60-s exposure to latex. This experiment indicates that discharge tubes grow at the tip. Completely assembled discharge tubes consisted of single, empty cylinders; however, incompletely discharged tubes had a cylinder-within-a-cylinder profile at the distal ends. This observation indicates that the discharge tube material emerges at the distal end by an eversion process. Finally, studies with cinematic Nomarski interference optics of spore tubes extruding across a water-air interphase indicate that all the material emerging from the growing tip of the tube is incorporated into the wall of the discharge tube. Evidence indicates that the polar filament of undischarged spores is a homogeneous coil of polar tube protein equivalent to the polar tube protein in discharged tubes.
微孢子虫孢子内的极丝以亚秒级速度作为管子排出。用乳胶颗粒脉冲标记1 - 3秒的赫氏格留虫孢子的排出管群体，其远端始终没有标记；在暴露于乳胶30至60秒后，排出管被完全标记。该实验表明排出管在尖端生长。完全组装好的排出管由单个空圆柱体组成；然而，未完全排出的管子在远端具有圆柱套圆柱的轮廓。这一观察结果表明排出管物质通过外翻过程在远端出现。最后，利用电影诺马斯基干涉光学对跨水 - 气界面挤出的孢子管进行的研究表明，从管子生长尖端出现的所有物质都并入了排出管的壁中。有证据表明未排出孢子的极丝是极管蛋白的均匀线圈，等同于已排出管中的极管蛋白。
