- A-Z
- Endocytobiosis and ...
- Volume 1
- Interactions of int...
- Autor(in)
- Seitenbereich
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047-059
- Zusammenfsg.
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Ultrastructure investigations on interactions of intracellular bacteria-like endocytobiotic microorganisms and nurse cell-oocyte in ovarien differentiation is the basis of the syncytial nature of the argasid ovary. The formation in the late differentiation phase of many closely and incomplete cell divisions arranged as nurse cell-oocytes occuping a common cytoplasm results from membrane fusion systems. The endocytobionts could be observed both in nurse cells and oocytes. They were most commonly observed during oogenesis before vitellogenesis. Nurse cell-oocyte and also oocyte-oocyte intercellular bridge systems are later modified to form the trophic cords. The trophic core, which undergoes a restructuring during the late differentiation phase, mediates nurse cell-oocyte interactions in this system. Oocytes, first recognizable during the early differentiation phase of oogenesis, retain connections to the trophic core and thus to the nutritive cords of the later ovariole phases. Transport of intracellular bacteria-like endocytobionts and other materials like mitochondria, microtubules, ribosomes and breakdown elements such as multi-vesicular bodies and dense bodies from the nurse cells occur from the trophic core, and thus to oocytes through the trophic cords as well as direct connections to the nurse cell-oocyte. The different phases of the oocytes contain endocytobionts and previously mentioned material similar in appearance to that present within the restructuring trophic core. The normal appearance of the oocyte nucleus, organelles and endocytobionts in cytoplasm suggest that these oocytes are not autolytic but rather are receiving the breakdown organisms and other materials from the restructuring trophic core. The formation of trophic cords elongates, maintaining their core connections, as oocytes become established in the oogenesis of the ovarioles during the late differentiation phases in the adults. Bacteria-like endocytobionts and other breakdown materials are transported to and accumulated from the apical trophic tissues of nurse cells, via the fusomal-like system into the oocytes where they are stored or utilized by the late differentiation phase. The interactions of intracellular bacteria-like endocytobionts from the nurse cells throughout the oocytes during oogenesis should lead to a clear understanding of the nutritional physiology and ecology of endocytobionts in the host habitat.