A large number of tetraploid Arabidopsis thaliana lines, generated by a rapid strategy, reveal high stability of neo-tetraploids during consecutive generations

Abstract

Arabidopsis thaliana has, in conjunction with A. arenosa, developed into a system for the molecular analysis of alloplolyploidy. However, there are very few Arabidopsis lines available to study autopolyploidy. In order to investigate polyploidy on a reliable basis, we have optimised conventional methodologies and developed a novel strategy for the rapid generation and identification of polyploids based on trichome branching patterns. The analysis of more than two dozen independently induced Arabidopsis lines has led to interesting observations concerning the relationship between cell size and ploidy levels and on the relative stability of tetraploidy in Arabidopsis over at least three consecutive generations. The most important finding of this work is that neo-tetraploid lines exhibit considerable stability through all the generations tested. The systematic generation of tetraploid collections through this strategy as well as the lines generated in this work will help to unravel the consequences of polyploidy, particularly tetraploidy, on the genome, on gene expression and on natural diversity in Arabidopsis.

Impact of natural genetic variation on the transcriptome of autotetraploid Arabidopsis thaliana

“…These lines were repeatedly assessed by flow cytometry and chromosome counts for their ploidy (ref. 21; Fig. 1C).…”

“…1A). Four recently generated independent tetraploid lines of the third generation, after induction, were used (21). Although tetraploid plants typically exhibited enlarged cells and tissues in comparison with diploids, overall structural morphology remained unchanged (Fig.…”

“…The tetraploid Ler-0 and Col-0 lines analyzed in this study exhibited high chromosome number stability during consecutive generations (21). We investigated the stability of the tetraploid transcriptome by analyzing microarray expression profiles of seedlings, two and three generations after induction.…”

Mutations in MYB3R1 and MYB3R4 Cause Pleiotropic Developmental Defects and Preferential Down-Regulation of Multiple G2/M-Specific Genes in Arabidopsis

“…Rosette leaves of the myb3r1 myb3r4 double mutant occasionally had extraordinarily large stomata and trichomes with supernumerary branches (Supplemental Fig. S1), which are characteristic of polyploid plants (Yu et al, 2009). When analyzed by flow cytometry, wild-type diploid leaves showed peaks at 2C, 4C, 8C, 16C, 32C, and sometimes 64C levels, with DNA levels higher than 2C generated by endoreduplication during leaf development (Fig.…”

Determining the Fate of Hybridized Genomes in the Allopolyploid Brassica napus

“…As B. rapa (A-subgenome) and B. oleracea (C-subgenome) are hybridized, the sterile hybrid (CA) may undergo genome duplication, giving rise to B. napus (CCAA). Genome doubling in the hybrids was either induced by colchicine treatment or occurred spontaneously to create the S 0 generation of B. napus (Lukens et al, 2006;Yu et al, 2009). Each lineage of B. napus represents a unique fertilization event.…”