The invention relates to flavin-NAL conjugates and to their applications in the field of genetic engineering. Depending on the nature of the flavin which is conjugated to the NAL, the conjugates according to the invention can be used either (1) as nucleases for specifically and efficiently cleaving target nucleic acid sequences in living cells, or (2) as carriers for specifically and efficiently addressing NALs, such as for example antisense oligonucleotides, inside the cells.
