Method for the preparation of a protein by yeasts using an inducible system, vectors and corresponding transformed strains

The present invention relates to a method for the preparation of a protein by yeasts, according to which: yeast cells which contain the following are cultured: a DNA sequence coding for the protein under the control of elements providing for its expression in yeasts, the elements comprising a transcription control sequence which is inducible by a complex formed by a receptor and a ligand, a DNA sequence which is functional in yeast, coding for the receptor, the receptor comprising two essential portions, one of which recognizes the ligand so as to form a complex with the ligand and the other binds to the said transcription control sequence; the portion of the receptor which recognizes the ligand is of higher eukaryotic origin, and the ligand is not necessary for the culturing of the cells but is capable of entering the cells when added to the culture medium, the ligand is added to the culture medium at an appropriate time point for induction, the synthesized protein is recovered.