Skip Navigation



MBE Advance Access published online on June 8, 2005
Molecular Biology and Evolution, doi:10.1093/molbev/msi186
This Article
Right arrow Advance Access manuscript (PDF) Freely available
Right arrow All Versions of this Article:
22/9/1929    most recent
msi186v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Navajas-Pérez, R.
Right arrow Articles by Garrido-Ramos, M. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Navajas-Pérez, R.
Right arrow Articles by Garrido-Ramos, M. A.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2005. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oupjournals.org
Accepted May 30, 2005

Research Article

The Evolution of Reproductive Systems and Sex-Determining Mechanisms Within Rumex (Polygonaceae) Inferred from Nuclear and Chloroplastidial Sequence Data

Rafael Navajas-Pérez 1, Roberto de la Herrán 1, Ginés López González 2, Manuel Jamilena 3, Rafael Lozano 3, Carmelo Ruiz Rejón 1, Manuel Ruiz Rejón 1, and Manuel A. Garrido-Ramos 1*

1 Departamento de Genética, Facultad de Ciencias, Universidad de Granada, 18071 Granada
2 CSIC, Real Jardín Botánico de Madrid, Madrid
3 Departamento de Biología Aplicada, Escuela Técnica Superior de Ingenieros Agrónomos, Universidad de Almería, Almería. SPAIN

* To whom correspondence should be addressed.
Manuel A. Garrido-Ramos, E-mail: mgarrido{at}ugr.es


  Abstract

The genus Rumex includes hermaphroditic, polygamous, gynodioecious, monoecious and dioecious species, the dioecious species being represented by different sex-determining mechanisms and sex-chromosome systems. Therefore, this genus represents an exceptional case study to test several hypotheses concerning the evolution of both mating systems and the genetic control of sex determination in plants. Here, we compare nuclear ITS and chloroplast intergenic sequences of 31 species of Rumex. Our phylogenetic analysis supports a systematic classification of the genus, which differs from that currently accepted. In contrast to the current view, this new phylogeny suggests a common origin for all Eurasian and American dioecious species of Rumex, with gynodioecy as an intermediate state on the way to dioecy. Our results support the contention that sex determination based on the balance between the number of X chromosomes and the number of autosomes (X/A balance) has evolved secondarily from male-determining Y mechanisms and that multiple sex-chromosome systems, XX/XY1Y2, were derived twice from an XX/XY system. The resulting phylogeny is consistent with a classification of Rumex species according to their basic chromosome number, implying that the evolution of Rumex species might have followed a process of chromosomal reduction from x=10 toward x=7 through intermediate stages (x=9 and x=8).


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.