This invention relates generally to the field of plant molecular biology.
More specifically, this invention relates to methods and reagents for the
temporally- and/or spatially-regulated expression of genes that affect
metabolically effective levels of cytokinins in plants, particularly in
plant seeds and related female reproductive tissue. This invention
further relates to transgenic plants having enhanced levels of cytokinin
expression wherein the transgenic plant exhibits useful characteristics,
such as improved seed size, decreased tip kernel abortion, increased seed
set during unfavorable environmental conditions, or stability of yield.
The present invention also provides compositions and methods for
regulating expression of heterologous nucleotide sequences in a plant.
Compositions comprise novel nucleotide sequences for seed-preferred
promoters known as eep1 and eep2. A method for expressing a heterologous
nucleotide sequence in a plant using the promoter sequences disclosed
herein is provided. The method comprises transforming a plant cell to
comprise a heterologous nucleotide sequence operably linked to one of the
promoters of the present invention and regenerating a stably transformed
plant from the transformed plant cell.