A chimeric plant-expressible gene, said gene comprising in the 5' to 3' direction:
a) a promoter region derived from a gene that is naturally expressed in a plant cell and that is capable of effecting mRNA transcription in the selected plant cell to be transformed, operably linked to
b) a structural DNA sequence encoding a polypeptide that permits the selection of transformed plant cells containing said chimeric gene by rendering said transformed plant cells resistant to an amount of an antibiotic that would be toxic to non-transformed plant cells, operably linked to
c) a non-translated region of a gene naturally expressed in plant cells, said region encoding a signal sequence for polyadenylation of mRNA.

A chimeric gene capable of expressing a polypeptide in plant cells comprising in sequence:
a) a promoter region from a gene which is naturally expressed in plant cells;
b) a 5' non-translated region;
c) a structural coding sequence encoding a neomycin phosphotransferase polypeptide; and
d) a 3' non-translated region of a gene naturally expressed in plant cells, said region encoding a signal sequence for polyadenylation of mRNA.