摘要
通过精巢染色体制片观察金鱼的生殖细胞染色体数,结合流式细胞仪测定成熟精子DNA含量,探讨了金鱼生殖细胞发生过程中染色体特征及产生的精子的倍性。结果表明,金鱼初级精母细胞大部分行正常减数分裂,形成50个二价体,另外还发现17.0%分裂相的二价体数呈现不同程度的加倍现象,观察到了二价体数为100、150、200、250、300,甚至远远超过300的分裂相,与鲫鲤远缘杂交导致生殖细胞染色体数加倍一致,不一样的是金鱼稳定产生DNA含量减半的精子。结果表明,近缘杂交和远缘杂交都可以导致生殖细胞染色体数加倍,但是否能产生染色体数加倍的功能性配子与杂交亲本亲缘关系的远近有关。
The previous studies had indicated that the distant crossing between red crucian carp（Carassius auratus red var.）and common carp（Cyprinus carpio L.）results in chromosomal double in germ cells.In order to explore the potential ability of polyploidization in the goldfish from close crossing,by observing the chromosomal spreads of germ cells in testis,combining the flow cytometer examined DNA content of sperms,we studied the chromosomal characterization of spermiogenesis and the ploidy of sperms in goldfish.The results showed that the majority of spermatocytes in goldfish had normal chromosomal behavior in meiosisⅠ,like chromosome pairing with 50 bivalents.Furthermore,the bivalent number of a part of germ cells in goldfish doubled obviously among 17.0% of all examined chromosomal spreads,the doubling showed 100,150,200,250,300 and even more bivalents,which is similar to the chromosomal number doubling in distant crossing between red crucian carp and common carp.Unlike distant crossing species,the goldfish stably produced haploid sperms though.Taken together,it was concluded that both close crossing and distant crossing lead to chromosome doubling in germ cell.However,the production of functional gametes in process of chromosome doubling depends mainly on the genetic relationship between the parents.
出处
《水产学报》
CAS
CSCD
北大核心
2010年第10期1502-1508,共7页
Journal of Fisheries of China
基金
国家自然科学基金青年项目(30901100)
国家杰出青年科学基金(30725028)
湖南省教育厅科学研究项目(09B060)
关键词
金鱼
生殖细胞染色体
减数分裂
二价体
流式细胞仪
Carassius auratus
chromosomal spreads of germ cells
meiosis
bivalent
flow cytometer
