Introns structure patterns of variation in nucleotide composition in <em>Arabidopsis thaliana</em> and rice protein-coding genes
2015
Ressayre, Adrienne | Glémin, Sylvain | Montalent, Pierre, P. | Serres Giardi, Laurana | Dillmann, Christine | Joets, Johann, J. | Génétique Quantitative et Evolution - Le Moulon (Génétique Végétale) (GQE-Le Moulon) ; Institut National de la Recherche Agronomique (INRA)-Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Department of Ecology and Genetics [Uppsala] (EBC) ; Uppsala University | Institut des Sciences de l'Evolution de Montpellier (UMR ISEM) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE) ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS) | Institut de Recherche en Horticulture et Semences (IRHS) ; Université d'Angers (UA)-Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | French INRA ; French CNRS ; Marie Curie IEF Grant SELFADAPT [623486] ; University of Paris-Sud
International audience
اظهر المزيد [+] اقل [-]إنجليزي. Plant genomes present a continuous range of variation in nucleotide composition (G+C content). In coding regions, G+C-poor species tend to have unimodal distributions of G+C content among genes within genomes and slight 50-30 gradients along genes. In contrast, G+C-rich species display bimodal distributions of G+C content among genes and steep 50-30 decreasing gradients along genes. The causes of these peculiar patterns are still poorly understood. Within two species (Arabidopsis thaliana and rice), each representative of one side of the continuum, we studied the consequences of intron presence on coding region and intron G+C content at different scales. By properly taking intron structure into account, we showed that, in both species, intron presence is associated with step changes in nucleotide, codon, and amino acid composition. This suggests that introns have a barrier effect structuring G+C content along genes and that previous continuous characterizations of the 50-30 gradients were artifactual. In external gene regions (located upstream first or downstream last introns), species-specific factors, such as GC-biased gene conversion, are shaping G+C contentwhereas in internal gene regions (surrounded by introns), G+C content is likely constrained to remain within a range common to both species.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
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تم تزويد هذا السجل من قبل Institut national de la recherche agronomique