Zoologisches Institut der Universität Münster, Münster, FRG.
Eur J Protistol. 1991 Feb 22;26(3-4):370-86. doi: 10.1016/S0932-4739(11)80158-6. Epub 2011 Nov 2.
The pregamic and metagamic nuclear divisions during conjugation of Euplotes octocarinatus and the development of new micro- and macronuclei were investigated with the help of phase contrast microscopy and a staining of the cells by aceto carmine. The most important stages are illustrated with microphotographs and a time table of the events based on experiments carried out at 26°C is presented. It is shown that E. octocarinatus has n = 35 chromosomes and that all of them enter the macronuclear anlage and undergo polytenisation before they break down into the short DNA-pieces typical of the adult macronucleus of hypotrich ciliates. The nuclear events suggest that, similar to what has been reported for E. patella, frequently sister nuclei become the pronuclei which should result in the formation of a high proportion of isogenic co-conjugant lines. A comparison of the nuclear events in heterotypic pairs (co-conjugants of different mating types) with those in homotypic pairs (co-conjugants of the same mating type) revealed no differences apart from a tendency of homotypic pairs to become arrested at the premeiotic division and then to separate. Although hundreds of cells were investigated, regeneration of pieces of the old macronucleus or fusion of fragments with a newly formed anlage, as is reported for certain other Euplotes species, has not been observed.
利用相差显微镜和醋酸卡红对细胞的染色，研究了八肋游仆虫接合过程中的配子核和配子核后核的分裂以及新的小核和大核的发育。重要的阶段用显微照片进行了说明，并根据在 26°C 进行的实验提出了一个基于时间的事件表。结果表明，E. octocarinatus 有 n = 35 条染色体，所有染色体都进入大核原基，并在它们分解成短的 DNA 片段之前经历多倍化，这些短的 DNA 片段是典型的低等纤毛虫的成体大核。核事件表明，与已报道的 E. patella 相似，姐妹核经常成为原核，这应该导致形成高比例的同系合子系。异型配对（不同交配型的合子）的核事件与同型配对（相同交配型的合子）的核事件进行比较，除了同型配对有在减数分裂前分裂并随后分离的趋势外，没有发现差异。尽管调查了数百个细胞，但没有观察到旧大核的片段再生或与新形成的原基融合的情况，而某些其他 Euplotes 物种有报道。
