title: Cytological studies on induced mitogynogenesis in Japanese flounder Paralichthys olivaceus (Temminck et Schlegel).
abstract: The effect of hydrostatic pressure treatment on the induction of mitogynogenesis in the eggs of Japanese flounder Paralichthys olivaceus (Temminck et Schlegel) by using heterospecific sperm were studied. Before treatment, the eggs were at metaphase of the first mitosis. The spindle was disassembled by the treatment and then resembled in its pretreatment position, and the chromosomes were rearranged, i.e., the first mitosis was not blocked. During the second mitotic cycle, only a monopolar spindle was assembled in each blastomere and the chromosomes doubled, but cell cleavage was blocked. In the third cycle, mitosis proceeded normally with a bipolar spindle in each blastomere. Flow cytometric analysis of ploidy demonstrated that mitogynogenetic larvae were all diploid. The ultraviolet light-irradiated sperm of the red sea bream (Pagrus major) was condensed, formed a dense chromatin body, and randomly entered one blastomere.
authors.affiliation: Beidaihe Central Experiment Station,Chinese Academy of Fishery Sciences,Qinhuangdao 066100,China.
authors.forename: Jilun
authors.initials: J
authors.lastname: Hou
authors.affiliation: Beidaihe Central Experiment Station,Chinese Academy of Fishery Sciences,Qinhuangdao 066100,China.
authors.forename: Guixing
authors.initials: G
authors.lastname: Wang
authors.affiliation: Beidaihe Central Experiment Station,Chinese Academy of Fishery Sciences,Qinhuangdao 066100,China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Centre for Applied Aquatic Genomics,Chinese Academy of Fishery Sciences,Beijing,100141,China.
authors.forename: Haijin
authors.initials: H
authors.lastname: Liu
mesh_terms: D000818:Animals; D001757:Blastomeres / Q000166:cytology; D002843:Chromatin; D004171:Diploidy; D004625:Embryo, Nonmammalian; D005260:Female; D005432:Flounder / Q000196:embryology / Q000235:genetics*; D006874:Hydrostatic Pressure; D007814:Larva; D008297:Male; D008677:Metaphase; D008938:Mitosis; D010063:Ovum / Q000166:cytology / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D002843:Chromatin
keywords: Cytology; Hydrostatic pressure; Japanese flounder Paralichthys olivaceus; Mitogynogenesis; Monopolar spindle