包囊游仆虫休眠包囊的超微结构研究

AN ULTRASTRUCTURAL STUDY ON RESTING CYST OF EUPLOTES ENCYSTICUS

包囊游仆虫休眠包囊中,各类纤毛器的纤毛基体上方的大部分纤毛杆退化,或仅保留毛基体,有时部分额腹棘毛的毛基体也瓦解消失。残留纤毛的纤毛杆周围微管和中央微管仍具有“9+2”结构特征,也有少数纤毛杆出现2套“9+2”微管共处于一层纤毛膜内的现象。毛基体中周围三联体微管的中央形成微管形结构聚合体,基体附属结构仅存在基体间连接及纤毛器托架的残余物;非纤毛区皮层表膜下未见微管层。纤毛区皮层含纤毛器腔周围微管层(相当于表膜下微管层)、纤毛器深部及附近的微管束和分散的微管群。并且,纤毛区皮层囊泡内含有呈不同形态的纤毛杆结构;大核核孔明显变大,核孔数目减少,核孔内膜附着染色质。

For resting cysts of Euplotes encysti-cus, in their various ciliatures, most of the ciliary shafts above the cilia kineto-somes are degenerated, or preserve their kinetosomes only. Sametimes, kinetosomes of certain frontal and ventral cirri are also disintegrated and disappeared. For remaining cilia, on their shafts, peripheral doublet microtubule (MT) and central pair of MTs still possess their structural pattern of '9 + 2'. In few ciliary shafts, the phenomena of 2 sets of '9 + 2' structures surrounded by a common sheath can also be seen. At the center of kinetoso-mal peripheral triplets (triplet MTs), aggregates of MT-like structures are for- med. For kinetosomal accessory structures, only residues of inter-kinetosomal connections and ciliature brackets can be seen. No MT layers can be seen under the pellicles of non-ciliated cortex. At the ciliated cortex, there are peripheral MT layers (corresponding to sub-pellicular MT layers) within the ciliature cavity, MT ribbons at (and near) the deeper parts of ciliature, and scattered MT groups. Besides, various shapes of ciliary shafts structures are seen within cortical vesicles of ciliated regions. Nuclear pores of macron-ucleus enlarged apparently, reduced in number, and, chromatin attached on the inner membrane of these nuclear pores.