| abstract |
Compositions and methods for modulating nucleotide sequence expression, particularly for modulating gene expression in plants, are provided. The compositions comprise precursor RNA constructs for the expression of an RNA precursor. The precursor RNA construct comprises a promoter that is expressed in a plant cell driving the expression of a precursor RNA having a microRNA. The miRNA is complementary or partially complementary to a portion of a target gene or nucleotide sequence and function to modulate expression of the target sequence or gene. In this manner, the RNA precursor construct can be designed to modulate expression of any nucleotide sequence of interest, either an endogenous plant gene or alternatively a transgene. The precursor RNA constructs may be used in combination with modulators to enhance the effect on gene expression. Expression of a modulator in the presence of the precursor RNA alters the accumulation of miRNAs and thus enhances the regulatory capabilities of miRNAs. The invention further comprises the use of a modulator to control gene expression via both siRNA and the miRNA pathway. Transformed plants, tissues, cells and seeds are also provided. |