Laboratory of Protozoology, Ocean University of China, Qingdao, China.
Eur J Protistol. 2009 Nov;45(4):292-304. doi: 10.1016/j.ejop.2009.07.002. Epub 2009 Sep 19.
Recent studies suggested that the marine ciliate Kiitricha Nozawa, 1941 represents a basal branch in the spirotrichs. The present study reflects the morphogenetical investigation of Kiitricha marina Nozawa, 1941. The results listed below show an extremely unusual developmental pattern compared with all other known forms in the class Spirotrichea or hypotrichs s. l. (i) The differentiation of the ciliary structures from the primordia occurs after cell division. This makes Kiitricha marina Nozawa, 1941 unique among hypotrichs s. l. (ii) Since the anlage of the undulating membranes in the opisthe derives from the division of the dedifferentiated parental structure and thus is not formed independently, Kiitricha marina Nozawa, 1941 is also unique among spirotrichs. (iii) Most somatic cirral structures appear in a post-anlage pattern, i.e. all cirri exhibit a primary arrangement in the sense that they are distributed as though they had just been segregated from the anlagen. (iv) Unlike most other known hypotrichs s. l., the undulating membrane-anlage does not contribute a frontal cirrus. (v) The dorsal kineties are formed in two ways: (a) from the posterior portion of the cirral anlagen which later generate the new dorsal kinety segments; and (b) by the irregular proliferation of dikinetids in the long dorsal kineties. (vi) All cirral anlagen are formed intrakinetally from the dedifferentiated parental cirri and develop in a primary mode. Taken collectively, these findings suggest that Kiitricha is a basal branching hypotrich and therefore a possible model for the ancestor of the hypotrichs s. l.
最近的研究表明，海洋纤毛虫 Kiitricha Nozawa, 1941 代表了螺旋体的一个基础分支。本研究反映了 Kiitricha marina Nozawa, 1941 的形态发生学研究。以下列出的结果显示了与所有其他已知的螺旋体或下毛类 s. l. 形式相比，一种极其不寻常的发育模式。(i) 纤毛结构从原基分化出来发生在细胞分裂之后。这使得 Kiitricha marina Nozawa, 1941 在所有下毛类 s. l. 中独一无二。(ii) 由于波动膜的原基在右体衍生自去分化的亲代结构的分裂，因此不是独立形成的，Kiitricha marina Nozawa, 1941 在螺旋体中也是独一无二的。(iii) 大多数体纤毛结构以-post-anlage 模式出现，即所有纤毛都表现出初级排列，即它们的分布方式好像它们刚刚从原基中分离出来。(iv) 与大多数其他已知的下毛类 s. l. 不同，波动膜原基不贡献一个前纤毛。(v) 背纤毛列以两种方式形成：(a) 来自纤毛原基的后部分，后者后来产生新的背纤毛列节段；(b) 由长背纤毛列中的二联体不规则增殖形成。(vi) 所有纤毛原基都是从去分化的亲代纤毛内在动基体中形成的，并以初级模式发育。总的来说，这些发现表明 Kiitricha 是一个基础分支的下毛类，因此可能是下毛类 s. l. 的祖先的模型。
