Abstract: An expression vector comprising a promoter capable of directing expression of a coding sequence in an angiosperm cell, and a 3' untranslated region of a rice .alpha.-amylase gene, wherein, after the coding sequence is inserted into the vector, the 3' untranslated region and the coding sequence are transcribed into a single mRNA. Also featured are methods of producing a polypeptide in angiosperm cells using such a vector.

Abstract: Sugar-responsive enhancers derived from cereal .alpha.-amylase genes. Also featured are expression vectors and other isolated DNA's containing such enhancers, as well as uses of the expression vectors.

Abstract: The present invention is directed to a method for producing a gene product by expressing a gene encoding the gene product in angiosperm host cells, comprising the steps of constructing a vector expressible in angiosperm host cells, the vector comprising a promoter region derived from an .alpha.-amylase gene of a plant, and a gene encoding a desired gene product; transforming a compatible angiosperm host cell with the vector; cultivating the resultant transformant host cell; subjecting the cultivated transformant host cell to a sugar-depleted or sugar-free condition to promote the expression of the gene under the control of the promoter region; and recovering the expressed gene product.

Abstract: Disclosed is a method for producing a gene product by expressing a gene encoding said gene product in plant host cells, comprising the steps of: constructing a vector expressible in plant host cells, the vector comprising a promoter region derived from an .alpha.-amylase gene of a plant, and a gene encoding a desired gene product; transforming a compatible plant host cell with the vector; cultivating the resultant transformant host cell; subjecting the cultivated transformant host cell to a sugar-depleted or sugar-free condition to promote the expression of the gene under the control of the promoter region; and recovering the expressed gene product. Also disclosed is a method for producing a gene product method which comprises the steps of: constructing a vector expressible in plant host cells, the vector comprising a promoter region derived from an .alpha.