The invention relates to regulatory sequences that regulate gene expression in the mesocarp and/or senescent leaves of certain plants. In certain embodiments, the invention is directed to abundant and selective expression of type 3 metallothionein-like genes in the mesocarp of a variety of plants including members of the Palme family. The invention also relates to methods of generating transgenic plants and plant tissues that comprise a nucleic acid of the invention. The invention further provides products derived from transgenic plants, plant materials or plant cells of the invention. Particular applications in oil palms are discussed. The invention further relates to nucleic acid constructs of the invention in cells of organisms other than plants.