Format

Send to

Choose Destination
See comment in PubMed Commons below
BMC Evol Biol. 2009 Aug 13;9:201. doi: 10.1186/1471-2148-9-201.

Loss of matK RNA editing in seed plant chloroplasts.

Author information

  • 1Institut für Biologie, Humboldt Universität zu Berlin, Molekulare Genetik, Berlin D-10115, Germany. tillichm@staff.hu-berlin.de

Abstract

BACKGROUND:

RNA editing in chloroplasts of angiosperms proceeds by C-to-U conversions at specific sites. Nuclear-encoded factors are required for the recognition of cis-elements located immediately upstream of editing sites. The ensemble of editing sites in a chloroplast genome differs widely between species, and editing sites are thought to evolve rapidly. However, large-scale analyses of the evolution of individual editing sites have not yet been undertaken.

RESULTS:

Here, we analyzed the evolution of two chloroplast editing sites, matK-2 and matK-3, for which DNA sequences from thousands of angiosperm species are available. Both sites are found in most major taxa, including deep-branching families such as the nymphaeaceae. However, 36 isolated taxa scattered across the entire tree lack a C at one of the two matK editing sites. Tests of several exemplary species from this in silico analysis of matK processing unexpectedly revealed that one of the two sites remain unedited in almost half of all species examined. A comparison of sequences between editors and non-editors showed that specific nucleotides co-evolve with the C at the matK editing sites, suggesting that these nucleotides are critical for editing-site recognition.

CONCLUSION:

(i) Both matK editing sites were present in the common ancestor of all angiosperms and have been independently lost multiple times during angiosperm evolution.(ii) The editing activities corresponding to matK-2 and matK-3 are unstable.(iii) A small number of third-codon positions in the vicinity of editing sites are selectively constrained independent of the presence of the editing site, most likely because of interacting RNA-binding proteins.

PMID:
19678945
PMCID:
PMC2744683
DOI:
10.1186/1471-2148-9-201
[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for PubMed Central
    Loading ...
    Support Center