## Abstract The teratogenic effect of ethanol on human and animal embryos is now well documented. Recent studies have clearly demonstrated that ethanol and related spindleโacting agents may additionally interfere with normal meiotic chromosome segregation during oocyte maturation, leading to the pr
Hold the germ cells, I'm on duty
โ Scribed by Cassandra G. Extavour
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 129 KB
- Volume
- 26
- Category
- Article
- ISSN
- 0265-9247
No coin nor oath required. For personal study only.
โฆ Synopsis
Abstract
Germ cell segregation and gamete production are developmental problems that all sexually reproducing species must solve in order to survive. Many people are familiar with the complex social structures of some insect species, where specialised castes of adult insects perform specific tasks, one of which is usually to guard the sexually reproductive queen. The parasitic wasp Copidosoma floridanum adds another level of complexity to the caste system: a fertilised egg produces both sterile, shortโlived โsoldierโ larvae and โreproductiveโ larvae that complete metamorphosis to produce sexually reproductive adults. How two morphologically and functionally distinct larval castes are produced by genetically identical groups of cells developing under the same environmental conditions is a baffling problem. A recent paper suggests that differential germ cell segregation during embryogenesis may be an event both necessary and sufficient for caste determination.1 BioEssays 26:1263โ1267, 2004. ยฉ 2004 Wiley Periodicals, Inc.
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Fluorescent reagentโlabelled PGCs isolated from the blood of 2โdayโold chick embryos were cultured on stroma cells derived from 5โdayโold germinal ridge in Medium 199 supplemented with 10% FBS, human IGFโ1, bovine FGFโb, and murine LIF. In 7 experiments, the number of MCs increased by an average of