Cell fusion as the formation mechanism of unreduced gametes in the gynogenetic diploid hybrid fish
نویسندگان
چکیده
The gynogenetic diploid hybrid clone line (GDH) derived from red crucian carp (♀ RCC) × common carp (♂ CC) possesses the unusual reproductive trait of producing unreduced diploid eggs. To identify the mechanism underlying this phenomenon, we examined the structure, in vivo developmental process and in vitro dynamic development of the GDH gonad. In summary, compared with RCC and CC, GDH showed certain special straits. First, a high frequency (84.7%) of germ cell fusion occurred in gonadal tissue culture in vitro as observed by time-lapse microscopy. Second, microstructural and ultrastructural observation showed numerous binucleated and multinucleated germ cells in the gonad, providing evidence of germ cell fusion in vivo. By contrast, in the diploid RCC and CC ovaries, neither cell fusion nor multinucleated cells were observed during the development of gonads. Third, the ovary of GDH remained at stage I for 10 months, whereas those of RCC and CC remained at that stage for 2 months, indicating that the GDH germ cells underwent abnormal development before meiosis. This report is the first to demonstrate that cell fusion facilitates the formation of unreduced gametes in vertebrates, which is a valuable finding for both evolutionary biology and reproductive biology.
منابع مشابه
Genomic constitution and atypical reproduction in polyploid and unisexual lineages of the Misgurnus loach, a teleost fish.
The loach (Misgurnus anguillicaudatus) is an excellent animal model to elucidate biological origin and evolutionary significance of genome duplication and unisexual reproduction because artificially induced and naturally occurring polyploids and parthenogenetic (gynogenetic, androgenetic) animals can be compared. First, we summarize the chromosome manipulation techniques to induce triploids and...
متن کاملTransient Activation of Apomixis in Sexual Neotriploids May Retain Genomically Altered States and Enhance Polyploid Establishment
Polyploid genomes evolve and follow a series of dynamic transfigurations along with adaptation and speciation. The initial formation of a new polyploid individual within a diploid population usually involves a triploid bridge, a two-step mechanism of cell fusions between ubiquitous (reduced) and rare (unreduced) gametes. The primary fusion event creates an intermediate triploid individual with ...
متن کاملانتhybridقال ژرم پلاسم سولانوم آکول به سیب زمینی زراعی با استفاده از هیبرید بین گونهای تریپلوئید
The commercial potato is an autotetraploid species. Certain allotetraploid species such as S. acaule despite theire identical ploidy level are not crossable with commercial potato due to their different endosperm balance numbers. The aim of this experiment was to investigate the possibility of germplasm transferring from allotetraploid species to cultivated potato by the use of diploid species ...
متن کاملانتhybridقال ژرم پلاسم سولانوم آکول به سیب زمینی زراعی با استفاده از هیبرید بین گونهای تریپلوئید
The commercial potato is an autotetraploid species. Certain allotetraploid species such as S. acaule despite theire identical ploidy level are not crossable with commercial potato due to their different endosperm balance numbers. The aim of this experiment was to investigate the possibility of germplasm transferring from allotetraploid species to cultivated potato by the use of diploid species ...
متن کاملInterspecific Hybridisation and Polyploidisation as Tools in Ornamental Plant Breeding
Interspecific hybridisation and polyploidy are recognized as the most important sources of evolution and domestication of flowering plants. In ornamental plant breeding these phenomena go hand in hand and can be observed in the breeding history of many ornamental crops (Rosa, Chrysanthemum, Gladiolus, Alstroemeria, Lilium, orchids etc). With lily as model crop techniques developed for overcomin...
متن کامل