ULTRASTRUCTURAL FEATURES OF COCOON-SHELL GLOBULES IN THE VITELLINE CELLS OF NEOOPHORAN PLATYHELMINTHES
ULTRASTRUCTURAL FEATURES OF COCOON-SHELL GLOBULES IN THE VITELLINE CELLS OF NEOOPHORAN PLATYHELMINTHES
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DOI：
10.1007/bf00027589
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发表时间：
1991-12-20
期刊：
影响因子：
2.6
通讯作者：
FALLENI, A
中科院分区：
文献类型：
--
作者：
GREMIGNI, V;FALLENI, A
Neophora的特征是存在由生殖器和卵黄器组成的复杂的雌性生殖腺。卵黄由卵黄细胞组成，这些细胞分化以产生和积累储备物质（蛋白质，脂质，糖原）和卵囊或茧壳的前体（酚类蛋白）。本文对几种新蚤类扁形动物卵黄细胞中的成壳球进行了超微结构和细胞化学的比较研究，结果表明，成壳球的内部结构可分为两种（或三种）主要类型。在第一个，小球内容的特点是由一个或多或少均匀的电子致密的子结构显然是由粗糙内质网和高尔基复合体产生的小泡反复聚结。这种类型的球状体的一个变体显示混合（或同心）的电子致密和半透明区域，产生类似于脑回旋的图案（“回旋图案”）。第二种类型的壳球结构显示了一种“多颗粒模式”，可能是由于反复融合的高尔基囊泡其次是不完全的聚结的电子致密的内容。比较不同类群的壳球结构有助于阐明扁形动物之间复杂的系统发育关系。
The Neoophora is characterized by the presence of complex female gonads composed of both germaria and vitellaria. The vitellaria are made up of vitelline cells that differentiate to produce and accumulate reserve substances (proteins, lipid, glycogen) and precursors of the egg capsule or cocoon shell (phenolic proteins). A comparative ultrastructural and cytochemical investigation of shell-forming globules from the vitelline cells of some neoophoran platyhelminths shows that the internal structures of the shell-forming globules can be grouped into two (or three) main types. In the first, globule content is characterized by a more or less homogeneous electron-dense substructure evidently arising from repeated coalescence of small vesicles produced by the rough endoplasmic reticulum and Golgi complex. A variant of this type of globule shows intermingling (or concentric) electron-dense and translucent areas producing a pattern resembling brain convolutions ('convoluted pattern'). The second type of shell-globule structure shows a 'multigranular pattern', presumably resulting from repeated fusions of Golgian vesicles followed by incomplete coalescence of the electron-dense content. Comparison of shell-globule structure in different taxa could be useful in elucidating some complex and still-unclear phylogenetic relationships among Platyhelminthes.