論文

査読有り
2015年8月

Evidence for a Common Origin of Homomorphic and Heteromorphic Sex Chromosomes in Distinct Spinacia Species

G3-GENES GENOMES GENETICS
  • Satoshi Fujito
  • ,
  • Satoshi Takahata
  • ,
  • Reimi Suzuki
  • ,
  • Yoichiro Hoshino
  • ,
  • Nobuko Ohmido
  • ,
  • Yasuyuki Onodera

5
8
開始ページ
1663
終了ページ
1673
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1534/g3.115.018671
出版者・発行元
GENETICS SOCIETY AMERICA

The dioecious genus Spinacia is thought to include two wild relatives (S. turkestanica Ilj. and S. tetrandra Stev.) of cultivated spinach (S. oleracea L.). In this study, nuclear and chloroplast sequences from 21 accessions of Spinacia germplasm and six spinach cultivars or lines were subjected to phylogenetic analysis to define the relationships among the three species. Maximum-likelihood sequence analysis suggested that the Spinacia plant samples could be classified into two monophyletic groups (Group 1 and Group 2): Group 1 consisted of all accessions, cultivars, and lines of S. oleracea L. and S. turkestanica Ilj. and two of five S. tetrandra Stev. accessions, whereas Group 2 was composed of the three remaining S. tetrandra Stev. accessions. By using flow cytometry, we detected a distinct difference in nuclear genome size between the groups. Group 2 also was characterized by a sexual dimorphism in inflorescence structure, which was not observed in Group 1. Interspecific crosses between the groups produced hybrids with drastically reduced pollen fertility and showed that the male is the heterogametic sex (XY) in Group 2, as is the case in S. oleracea L. (Group 1). Cytogenetic and DNA marker analyses suggested that Group 1 and Group 2 have homomorphic and heteromorphic sex chromosome pairs (XY), respectively, and that the sex chromosome pairs of the two groups evolved from a common ancestral pair. Our data suggest that the Spinacia genus may serve as a good model for investigation of evolutionary mechanisms underlying the emergence of heteromorphic sex chromosome pairs from ancestral homomorphic pairs.

Web of Science ® 被引用回数 : 11

リンク情報
DOI
https://doi.org/10.1534/g3.115.018671
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/26048564
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000359265800013&DestApp=WOS_CPL