Michel Caboche

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The analysis of the first plant genomes provided unexpected evidence for genome duplication events in species that had previously been considered as true diploids on the basis of their genetics. These polyploidization events may have had important consequences in plant evolution, in particular for species radiation and adaptation and for the modulation of(More)
In Arabidopsis, proanthocyanidins specifically accumulate in the endothelium during early seed development. At least three TRANSPARENT TESTA (TT) genes, TT2, TT8, and TTG1, are necessary for the normal expression of several flavonoid structural genes in immature seed, such as DIHYDROFLAVONOL-4-REDUCTASE and BANYULS (BAN). TT8 and TTG1 were characterized(More)
The complete sequence of the Arabidopsis thaliana genome revealed thousands of previously unsuspected genes, many of which cannot be ascribed even putative functions. One of the largest and most enigmatic gene families discovered in this way is characterized by tandem arrays of pentatricopeptide repeats (PPRs). We describe a detailed bioinformatic analysis(More)
The TRANSPARENT TESTA8 (TT8) locus is involved in the regulation of flavonoid biosynthesis in Arabidopsis. The tt8-3 allele was isolated from a T-DNA-mutagenized Arabidopsis collection and found to be tagged by an integrative molecule, thus permitting the cloning and sequencing of the TT8 gene. TT8 identity was confirmed by complementation of tt8-3 and(More)
Transposable elements can be identified by their ability to induce mutant alleles at new loci. The retrotransposon family is thought to transpose through an RNA intermediate and has many similarities to vertebrate proretroviruses. In plants, retrotransposons have been described in maize, Arabidopsis and wheat, and non-viral retroposons in maize. Most of(More)
Genetic analyses have demonstrated that together with TTG1, a WD-repeat (WDR) protein, TT2 (MYB), and TT8 (bHLH) are necessary for the correct expression of BANYULS (BAN). This gene codes for the core enzyme of proanthocyanidin biosynthesis in Arabidopsis thaliana seed coat. The interplays of TT2, TT8, and their closest MYB/bHLH relatives, with TTG1 and the(More)
Flavonoids are secondary metabolites that accumulate in most plant seeds and are involved in physiological functions such as dormancy or viability. This review presents a current view of the genetic and biochemical control of flavonoid metabolism during seed development. It focuses mainly on proanthocyanidin accumulation in Arabidopsis, with comparisons to(More)
Anthocyanidin reductase encoded by the BANYULS (BAN) gene is the core enzyme in proanthocyanidin (PA) biosynthesis. Here, we analyzed the developmental mechanisms that regulate the spatiotemporal expression of BAN in the developing Arabidopsis seed coat. PA-accumulating cells were localized histochemically in the inner integument (seed body and micropyle)(More)
Screening for seed pigmentation phenotypes in Arabidopsis led to the isolation of three allelic yellow-seeded mutants, which defined the novel TRANSPARENT TESTA16 (TT16) locus. Cloning of TT16 was performed by T-DNA tagging and confirmed by genetic complementation and sequencing of two mutant alleles. TT16 encodes the ARABIDOPSIS BSISTER (ABS) MADS domain(More)
The Arabidopsis thaliana transparent testa10 (tt10) mutant exhibits a delay in developmentally determined browning of the seed coat, also called the testa. Seed coat browning is caused by the oxidation of flavonoids, particularly proanthocyanidins, which are polymers of flavan-3-ol subunits such as epicatechin and catechin. The tt10 mutant seeds accumulate(More)