A Z-shaped construct having the capacity to hybridize to double stranded DNA in a trans fashion to affect transcription is produced from at least two oligonucleotides, connected to each other, wherein the oligonucleotides are connected to one another through one of sequence specific Watson-Crick base pairing; a covalent linker or a covalent bond directly between the backbones or the bases of said oligonucleotides; or a non-covalent linker or a non-covalent bond directly between the backbones or the bases of said oligonucleotides.