DA1 encodes a putative ubiquitin receptor.DA1R358K isan arginine-to-lysine change in a conserved amino acid at position 358 and the mutant protein has a negative activity toward DA1 and DA1-related protein.Overexpression of a DA1R358K cDNA dramatically increases seed and organ size of Arabidopsis thaliana.Seed sizeis an important agronomic traitin oil crops.