Cellular signal-responsive gene transcriptional regulation system

摘要

A gene complex-forming material which comprises a water-soluble polymer having a peptide containing an amino acid sequence serving as the substrate of an intracellular signal-responsive enzyme and basic amino acids imparting cationic nature; a gene complex composed of this gene complex-forming material with a gene; and a gene transfer method and a gene transfer agent with the use of the same. Namely, a novel material and a method wherein the cationic moiety of the peptide and the gene form a rigid ion complex to give a stable gene complex, and, upon a cellular signal response, the positive charge of the cationic moiety of the peptide is neutralized or disappears and the gene complex is broken in the cell to thereby release the gene, thus activating the gene transferred into specific cells. The neutralization or disappearance of the positive charge can be achieved by, for example, phosphorylation with protein kinase A or cleavage by caspase.