|New approach to fish oocyte vitellogenesis|
Le Menn, F.; Davail, B.; Pelissero, C.; Ndiaye, P.; Bon, E.; Perazzolo, L.; Rodriguez, J.N. (2000). New approach to fish oocyte vitellogenesis, in: Norberg, B. et al. (Ed.) Proceedings of the 6th International Symposium on the Reproductive Physiology of Fish, Bergen, Norway, July 4-9, 1999. pp. 281-284
In: Norberg, B. et al. (Ed.) (2000). Proceedings of the 6th International Symposium on the Reproductive Physiology of Fish, Bergen, Norway, July 4-9, 1999. Department of Fisheries and Marine Biology, University of Bergen: Bergen. ISBN 82-7461-048-2. 499 pp., more
In: International Symposium on the Reproductive Physiology of Fish. Museo Nacional de Ciencias Naturales, more
|Authors|| || Top |
- Le Menn, F.
- Davail, B.
- Pelissero, C.
- Ndiaye, P.
- Bon, E.
- Perazzolo, L.
- Rodriguez, J.N.
It is during vitellogenesis that, in oviparous vertebrates, the oocyte accumulates the egg nutritional reserves, which in fish mainly originate from the incorporation of vitellogenin (VTG) and lipids. The yolk is the result of exogenous material processed within the ooplasm for use by the embryo and the larvae during their development. Numerous ultrastructural observations show clearly that endocytosis occurs simultaneously for the different constituants of the yolk. Nevertheless there are two successive phases: (i) a type I vitellogenesis when lipid accumulation predominates over incorporation of VTG, which latter is only detectable by electron microscopy, and also when externa zona radiata is deposited (ii) and a type II vitellogenesis when endocytosis of VTG is largely predominant over lipid uptake, and when interna zona radiata is deposited. Recent studies underline the importance of cellular tools being set up during previtellogenesis to prepare the endocytotic activity of the oocyte during vitellogenesis.