Abstract: A process is described for producing a polypeptide by cultivating a plant whose genome contains a recombinant DNA. The recombinant DNA includes:a) a first DNA sequence which encodes a precursor of a 2S albumin; andb) a heterologous second DNA sequence that encodes the polypeptide and that is inserted into, or replaces at least in part, a hypervariable region of the first DNA between codons which code for fourth and fifth cysteine residues of the large subunit of the 2S albumin. The ends of the second DNA sequence are each linked to one or more codons that encode one or more amino acid residues, to define first selectively cleavable border sites surrounding the polypeptide for separating the polypeptide from surrounding parts of the 2S albumin; and the hypervariable region, containing the second DNA sequence, encodes no more than approximately the same number of amino acids as are encoded by the hypervariable region without the second DNA sequence.