FIELD: biotechnology, molecular biology, biochemistry. SUBSTANCE: invention relates to nucleic acid structure for expression of active substance that is activated by enzyme protease releasing from mammalian cells and can be used in genetic therapy. Structure involves the following components: a) at least one promoter element; b) at least one DNA sequence that encodes active substance (protein B); c) at least one DNA sequence that encodes amino acid sequence (structural part C) that can be cleaved specifically by enzyme that is released from mammalian cells; d) at least one DNA sequence that encodes peptide or protein (structural part D) that binds with corresponding active compound (protein B) through cleavable amino acid sequence (structural part C) and inhibits activity of this active compound (protein B). The advantage of invention involves the development of structure that can release active substance with using proteases producing by cells. EFFECT: valuable biological properties of structure. 16 cl, 3 dwg, 2 tbl
