HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
理学院・理学研究院  >
雑誌発表論文等  >

Abortive meiosis in the oogenesis of parthenogenetic Daphnia pulex

CR18-7_833-840.pdf579.17 kBPDF見る/開く

タイトル: Abortive meiosis in the oogenesis of parthenogenetic Daphnia pulex
著者: Hiruta, Chizue 著作を一覧する
Nishida, Chizuko 著作を一覧する
Tochinai, Shin 著作を一覧する
キーワード: Daphnia pulex
Diploidy maintenance
発行日: 2010年11月
出版者: Springer Netherlands
誌名: Chromosome Research
巻: 18
号: 7
開始ページ: 833
終了ページ: 840
出版社 DOI: 10.1007/s10577-010-9159-2
PMID: 20949314
抄録: Most daphnid species adopt parthenogenesis and sexual reproduction differentially in response to varied environmental cues, resulting in the production of diploid progenies in both cases. Previous studies have reportedly suggested that daphnids produce their parthenogenetic eggs via apomixis; the nuclear division of mature oocytes should be an equational division similar to somatic mitosis. However, it seems premature to conclude that this has been unequivocally established in any daphnids. Therefore, the objective of our research was to precisely reveal the process and mechanism of parthenogenetic oogenesis and maintenance of diploidy in Daphnia pulex through histology, karyology, and immunohistochemistry. We found that when a parthenogenetic egg entered the first meiosis, division was arrested in the early first anaphase. Then, two half-bivalents, which were dismembered from each bivalent, moved back to the equatorial plate and assembled to form a diploid equatorial plate. Finally, the sister chromatids were separated and moved to opposite poles in the same manner as the second meiotic division followed by the extrusion of one extremely small daughter cell (resembling a polar body). These results suggest that parthenogenetic D. pulex do not adopt typical apomixis. We hypothesize that D. pulex switches reproductive mode depending on whether the egg is fertilized or not.
Rights: The final publication is available at
資料タイプ: article (author version)
出現コレクション:雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

提供者: 栃内 新


本サイトに関するご意見・お問い合わせは repo at へお願いします。 - 北海道大学