- THIS ARTICLE
- Full Text
- Full Text (PDF)
- Supporting Information
-
All Versions of this Article:
genetics.109.103580v1
182/4/1109 most recent - Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Email this article to a friend
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Howell, E. C.
- Articles by Filatov, D. A.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Howell, E. C.
- Articles by Filatov, D. A.
Originally published as Genetics Published Articles Ahead of Print on May 17, 2009.
Genetics, Vol. 182, 1109-1115, August 2009, Copyright © 2009
doi:10.1534/genetics.109.103580
Evolution of Neo-Sex Chromosomes in Silene diclinis
Elaine C. Howell*,
Susan J. Armstrong* and
Dmitry A. Filatov
,1
* School of Biosciences, University of Birmingham, Birmingham B15 2TT, United Kingdom and Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
1 Corresponding author: Department of Plant Sciences, University of Oxford, South Parks Rd., Oxford OX1 3RB, United Kingdom.
E-mail: dmitry.filatov{at}plants.ox.ac.uk
A small cluster of dioecious species in the plant genus Silene has evolved chromosomal sex determination and sex chromosomes relatively recently, within the last 10 million years (MY). Five dioecious Silene species (section Elisanthe) are very closely related (1–2 MY of divergence) and it was previously thought that all five have similar sex chromosomes. Here we demonstrate that in one of these species, Silene diclinis, the sex chromosomes have been significantly rearranged, resulting in the formation of neo-sex chromosomes. Fluorescence in situ hybridization with genic and repetitive probes revealed that in S. diclinis a reciprocal translocation has occurred between the ancestral Y chromosome and an autosome, resulting in chromosomes designated Y1 and Y2. Both Y1 and Y2 chromosomes are male specific. Y1 pairs with the X chromosome and with the autosome (the neo-X), which cosegregates with X. Y2 pairs only with the neo-X, forming a chain X-Y1-neo-X-Y2 in male meiosis. Despite very recent formation of the neo-sex chromosomes in S. diclinis, they are present in all surveyed individuals throughout the species range. Evolution of neo-sex chromosomes may be the cause of partial reproductive isolation of this species and could have been the isolating mechanism that drove speciation of S. diclinis.
 |