A hyperactive quantitative trait locus allele of Arabidopsis BRX contributes to natural variation in root growth vigor.

Détails

ID Serval
serval:BIB_D8FC9EB1E9A8
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
A hyperactive quantitative trait locus allele of Arabidopsis BRX contributes to natural variation in root growth vigor.
Périodique
Proceedings of the National Academy of Sciences of the United States of America
Auteur(s)
Beuchat J., Li S., Ragni L., Shindo C., Kohn M.H., Hardtke C.S.
ISSN
1091-6490 (Electronic)
ISSN-L
0027-8424
Statut éditorial
Publié
Date de publication
2010
Volume
107
Numéro
18
Pages
8475-8480
Langue
anglais
Résumé
Quantitative trait loci analysis of natural Arabidopsis thaliana accessions is increasingly exploited for gene isolation. However, to date this has mostly revealed deleterious mutations. Among them, a loss-of-function allele identified the root growth regulator BREVIS RADIX (BRX). Here we present evidence that BRX and the paralogous BRX-LIKE (BRXL) genes are under selective constraint in monocotyledons as well as dicotyledons. Unexpectedly, however, whereas none of the Arabidopsis orthologs except AtBRXL1 could complement brx null mutants when expressed constitutively, nearly all monocotyledon BRXLs tested could. Thus, BRXL proteins seem to be more diversified in dicotyledons than in monocotyledons. This functional diversification was correlated with accelerated rates of sequence divergence in the N-terminal regions. Population genetic analyses of 30 haplotypes are suggestive of an adaptive role of AtBRX and AtBRXL1. In two accessions, Lc-0 and Lov-5, seven amino acids are deleted in the variable region between the highly conserved C-terminal, so-called BRX domains. Genotyping of 42 additional accessions also found this deletion in Kz-1, Pu2-7, and Ws-0. In segregating recombinant inbred lines, the Lc-0 allele (AtBRX(Lc-0)) conferred significantly enhanced root growth. Moreover, when constitutively expressed in the same regulatory context, AtBRX(Lc-0) complemented brx mutants more efficiently than an allele without deletion. The same was observed for AtBRXL1, which compared with AtBRX carries a 13 amino acid deletion that encompasses the deletion found in AtBRX(Lc-0). Thus, the AtBRX(Lc-0) allele seems to contribute to natural variation in root growth vigor and provides a rare example of an experimentally confirmed, hyperactive allelic variant.
Mots-clé
Alleles, Alternative Splicing, Amino Acid Sequence, Arabidopsis/chemistry, Arabidopsis/genetics, Arabidopsis Proteins/chemistry, Arabidopsis Proteins/genetics, Evolution, Molecular, Gene Deletion, Haplotypes, Molecular Sequence Data, Phylogeny, Plant Roots/genetics, Plant Roots/growth & development, Quantitative Trait Loci, Sequence Alignment
Pubmed
Web of science
Open Access
Oui
Création de la notice
21/04/2010 19:05
Dernière modification de la notice
09/05/2019 1:59
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