Skip Navigation



MBE Advance Access published online on September 18, 2006
Molecular Biology and Evolution, doi:10.1093/molbev/msl119
This Article
Right arrow Advance Access manuscript (PDF) Freely available
Right arrow Supplementary Material
Right arrow All Versions of this Article:
23/12/2316    most recent
msl119v1
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 Mestrovic, N.
Right arrow Articles by Plohl, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mestrovic, N.
Right arrow Articles by Plohl, M.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2006. 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@oxfordjournals.org
Accepted August 23, 2006

Research Article

Interplay of Selective Pressure and Stochastic Events Directs Evolution of the MEL172 Satellite DNA Library in Root-knot Nematodes

Nevenka Mestrovic 1, Philippe Castagnone-Sereno 2, and Miroslav Plohl 1 *

1 Department of Molecular Biology, Rudder Boskovic Institute, Zagreb, Croatia; and Interactions Plantes-Microorganismes et Santé Végétale, INRA/UNSA/CNRS, Sophia Antipolis, France; Rudder Boskovic Institute, Bijenicka 54, HR-10002 Zagreb, Croatia
2 Department of Molecular Biology, Rudder Boskovic Institute, Zagreb, Croatia; and Interactions Plantes-Microorganismes et Santé Végétale, INRA/UNSA/CNRS, Sophia Antipolis, France; UMR1064 Interactions Plantes-Microorganismes et Santé Végétale, INRA/UNSA/CNRS, 400 Route des Chappes, BP167, 06903 Sophia Antipolis Cedex, France

* To whom correspondence should be addressed.
Miroslav Plohl, E-mail: plohl{at}irb.hr


  Abstract

According to the library model, related species can have in common satellite DNA families amplified in differing abundances, but reasons for persistence of particular sequences in the library during long periods of time are poorly understood. In this paper we characterize three related satellite DNAs coexisting in the form of a library in mitotic parthenogenetic root-knot nematodes of the genus Meloidogyne. Due to sequence similarity and conserved monomer length of 172 bp, this group of satellite DNAs is named MEL172. Analysis of sequence variability patterns among monomers of three MEL172 satellites revealed two low variable domains highly reluctant to sequence changes, two moderately variable domains characterized by limited number of mutations, and one highly variable domain. The latter domain is prone to rapid spread and homogenization of changes. Comparison of the three MEL172 consensus sequences shows that the low variable domains have 6 % changed nucleotide positions, the moderately variable domains have 48 %, while 78 % divergence is concentrated in the highly variable domain. Conserved distribution of intersatellite variability might indicate a complex pattern of interactions in heterochromatin which limits the range and phasing of allowed changes, implying a possible selection imposed on monomer sequences. The lack of fixed species-diagnostic mutations in each of the examined MEL172 satellites suggests that they existed in unaltered form in a common ancestor of extant species. Consequently, the evolution of these satellites seems to be driven by interplay of selective constraints and stochastic events. We propose that new satellites were derived from an ancestral progenitor sequence by nonrandom accumulation of mutations due to selective pressure on particular sequence segments. In the library of particular taxa, established satellites might be subject to differential amplification at chance due to stochastic mechanisms of concerted evolution.

Keywords: satellite DNA library; sequence variability; concerted evolution; selective pressure; parthenogenesis; root-knot nematode.
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.