瘦尾虫的小核在无性繁殖周期中对细胞形态结构的影响

通过显微切割建立瘦尾虫无小核细胞系,并与原细胞系及切割后再生的有小核细胞系进行对照观察。结果表明,无小核细胞的形态结构,尤其是口器出现高比率的畸形。在生长静止期,无小核细胞系群体中约23 % (36/155)的细胞完全失去了波动膜。与此同时,这些细胞的口围带也显出异常。一些无小核细胞的大核也出现异常,有的细胞仅含有1枚大核,有的则含有4枚,而不是通常的2枚;还有少数细胞的大核在非细胞分裂期进行分裂。上述结果提示,在无性繁殖周期中,瘦尾虫的小核对于维持正常的细胞形态结构、尤其是保持胞口结构的稳定性和大核数的恒定起着重要的作用动物学报52 (2) : 383 -388 , 2006]。

Micronuclear influence on the cell morphological structures in Uroleptus sp. (Ciliata, Protozoa) during asexual propagation

Amicronucleate cell lines of a spirotrichous ciliate Uroleptus sp. were generated by microsurgery. Compared with the normal cells and the micronucleates regenerated after microsurgery, the amicronucleates exhibited a higher rate of abnormality in the cell morphological structures, especially in undulating membranes (UM) and adoral zone of membranelles (AZM). During stationary phase, about 23% of amicronucleate cells (36/155) entirely lost their UM,and these cells showed abnormal AZM at the same time. Furthermore, some amicronucleates showed an abnormal number of macronuclei, e.g., only one macronucleus in some cells and four macronuclei in others replaced the normal two,and the macronuclei divided in the non-dividing phase in a few of the cells. The result suggests that the micronucleus of Uroleptus sp. is indispensable for sustaining the normal cell morphological structures, especially in the stabilization of the oral apparatus, and for maintaining the normal number of macronuclei.