In Arabidopsis hybrids and Hybrid Mimics, up-regulation of cell wall biogenesis is associated with the increased plant size.

Hybrid breeding is of economic importance in agriculture for increasing yield, yet the basis of heterosis is not well understood. In Arabidopsis, crosses between different accessions produce hybrids with different levels of heterosis relative to parental phenotypes in biomass. In all hybrids, the advantage of the F1 hybrid in both phenotypic uniformity and yield gain is lost in the heterogeneous F2.

The histone modification H3 lysine 27 tri-methylation has conserved gene regulatory roles in the triplicated genome of Brassica rapa L.

Brassica rapa L. is an important vegetable and oilseed crop. We investigated the distribution of the histone mark tri-methylation of H3K27 (H3K27me3) in B.

Arabidopsis Polycomb Repressive Complex 2 binding sites contain putative GAGA factor binding motifs within coding regions of genes.

Background: Polycomb Repressive Complex 2 (PRC2) is an essential regulator of gene expression that maintains genes in a repressed state by marking chromatin with trimethylated Histone H3 lysine 27 (H3K27me3). In Arabidopsis, loss of PRC2 function leads to pleiotropic effects on growth and development thought to be due to ectopic expression of seed and embryo-specific genes. While there is some understanding of the mechanisms by which specific genes are targeted by PRC2 in animal systems, it is still not clear how PRC2 is recruited to specific regions of plant genomes.

The VQ motif protein IKU1 regulates endosperm growth and seed size in Arabidopsis.

Arabidopsis seed size is regulated by the IKU pathway that includes IKU2 (a leucine-rich repeat kinase) and MINI3 (a WRKY transcription factor). We report the cloning of the IKU1 (At2g35230) gene. iku1 mutants cause reduced endosperm growth and the production of small seeds.

MINISEED3 (MINI3), a WRKY family gene, and HAIKU2 (IKU2), a leucine-rich repeat (LRR) KINASE gene, are regulators of seed size in Arabidopsis.

We have identified mutant alleles of two sporophytically acting genes, HAIKU2 (IKU2) and MINISEED3 (MINI3). Homozygotes of these alleles produce a small seed phenotype associated with reduced growth and early cellularization of the endosperm. This phenotype is similar to that described for another seed size gene, IKU1.