%0 Journal Article
%T Rapid evolutionary change of common bean (Phaseolus vulgaris L) plastome, and the genomic diversification of legume chloroplasts
%A Xianwu Guo
%A Santiago Castillo-Ram¨ªrez
%A V¨ªctor Gonz¨¢lez
%A Patricia Bustos
%A Jos¨¦ Lu¨ªs Fern¨¢ndez-V¨¢zquez
%A Rosa Santamar¨ªa
%A Jes¨²s Arellano
%A Miguel A Cevallos
%A Guillermo D¨¢vila
%J BMC Genomics
%D 2007
%I BioMed Central
%R 10.1186/1471-2164-8-228
%X We sequenced the complete genome of the common bean (Phaseolus vulgaris cv. Negro Jamapa) chloroplast. The plastome of P. vulgaris is a 150,285 bp circular molecule. It has gene content similar to that of other legume plastomes, but contains two pseudogenes, rpl33 and rps16. A distinct inversion occurred at the junction points of trnH-GUG/rpl14 and rps19/rps8, as in adzuki bean [1]. These two pseudogenes and the inversion were confirmed in 10 varieties representing the two domestication centers of the bean. Genomic comparative analysis indicated that inversions generally occur in legume plastomes and the magnitude and localization of insertions/deletions (indels) also vary. The analysis of repeat sequences demonstrated that patterns and sequences of tandem repeats had an important impact on sequence diversification between legume plastomes and tandem repeats did not belong to dispersed repeats. Interestingly, P. vulgaris plastome had higher evolutionary rates of change on both genomic and gene levels than G. max, which could be the consequence of pressure from both mutation and natural selection.Legume chloroplast genomes are widely diversified in gene content, gene order, indel structure, abundance and localization of repetitive sequences, intracellular sequence exchange and evolutionary rates. The P. vulgaris plastome is a rapidly evolving genome.Chloroplasts are derived from an endosymbiotic cyanobacterium that invaded the eukaryotic cell a billion years ago. During the evolutionary process from endosymbiont to contemporary organelles, the cyanobacterium lost the bulk of its genome and retained the genes encoding the photosynthesis machinery and the components of several chemical pathways. During this process, it also acquired many host-derived properties and was thus transformed into a distinct organelle: the chloroplast.Angiosperm chloroplast genomes present a similar gene content and gene order. They are circular molecules that can also be present in linear fo
%U http://www.biomedcentral.com/1471-2164/8/228