Identification of Nuage-like Structures in the Panoistic Ovarioles of the German Cockroach Blattella germanica (Linnaeus)
Other Title
德國蜚蠊無營養細胞型微卵管中似生殖雲構造之偵測鑑定
Journal
臺灣昆蟲
Journal Volume
28
Journal Issue
1
Start Page
1
End Page
10
Date Issued
2008-03
Author(s)
Abstract
在某些具有營養細胞型微卵管的昆蟲當中，母系生殖漿在卵發育的過程形成，而且生殖漿內所含生殖細胞決定物質係來自於營養細胞的生殖雲。然而，在不具有營養細胞的無營養細胞型微卵管中，母系生殖漿或生殖雲是否存在仍屬未定。爲了研究這個問題，我們用一個可辨識最保守之生殖細胞標記分子Vasa的高度交叉反應性抗體對德國蜚蠊(Blattella germanica) 的無營養細胞型微卵管進行免疫染色。實驗結果顯示在剛分化的卵母細胞以及在卵黃生成早、中期的卵母細胞，較集中的Vasa訊號出現在核膜周圍。然而，免疫染色訊號在一些卵黃生成中期的卵母細胞之核膜外緣呈現不連續之點狀分佈，而接著在較晚期的卵母細胞，染色訊號便無法偵測得到。在即將被排出體外的生熟卵中，Vasa訊號出現在充滿卵黃的卵外緣；然而Vasa訊號並無聚集在卵腔內部任何地方的跡象。由上述結果顯示，在德國蜚蠊的微卵管中，生殖雲存在於卵黃發育中期以前的卵母細胞；然而在卵黃發育後期，生殖雲並不參與母系生殖漿的組成。
In some insects with meriostic ovarioles, maternal germ plasm is assembled during oogenesis and contains germline determinants that originated from the perinuclear nuage in the nurse cells. However, in insects with panoistic ovarioles containing no nurse cells, it is uncertain whether or not they contain maternal germ plasm or nuage. In order to approach this question, we used a cross-reacting antibody against the most conserved germline marker Vasa to stain the panoistic ovarioles dissected from the adult German cockroach Blattella germanica. This antibody cross-reacted with the Vasa signals in the perinuclear nuage-like structures of young oocytes and some oocytes bearing early and mid-vitellogenesis. However, staining signals in the nuclear periphery broke down in late oocytes. In the mature eggs subjected to oviposition, Vasa signals were identified in the cortex of the yolk, but a subcellular localization of Vasa signals was undetectable. This suggests that nuage exists in oocytes by mid vitellogenesis but it may not be involved in the assembly of a maternal germ plasm localized in oocytes bearing late vitellogenesis in B. germanica.
Subjects
德國蜚蠊
生殖細胞
生殖漿
生殖雲
Vasa
Blattella germanica
germ cell
germ plasm
nuage
Type
journal article