Patent ID: 7525012

Claim:
A method for inducing plant somatic embryo formation comprising the steps of: a) transforming plant cells in culture with the following: (i) a first DNA construct encoding a gene which promotes somatic embryogenesis, wherein said gene is under the control of an inducible promoter and wherein said gene is a Lec1 gene_and wherein said inducible promoter comprises a binding site selected from the group consisting of a LexA-binding site and a GAL4-binding site operatively linked to a first promoter; and (ii) a second DNA construct encoding a transcription factor and having the following elements in the 5′ to 3′ direction: A) a second promoter, B) DNA encoding a DNA-binding domain selected from the group consisting of a bacterial repressor LexA DNA-binding domain and a GAL4 DNA-binding domain, C) DNA encoding a transactivating domain of VP16, and D) DNA encoding a regulatory domain selected from the group consisting of an estrogen receptor regulatory domain and a glucocorticoid receptor regulatory domain and wherein said transcription factor stimulates transcription from said inducible promoter of (i) in the presence of an inducer of said transcription factor; and b) culturing said transformed plant cells in the absence of added plant hormones but in the presence of said inducer to induce the formation of somatic embryos, wherein the inducer is selected from the group consisting of 17-β-estradiol, 4-hydroxyl tamoxifen, dexamethasone, triamcinolone acetonide, betamethasone and hydrocortisone.