23] Intracellular delivery of nucleic acids and transcription factors by cationic liposomes

Abstract

This chapter focuses on the intracellular delivery of nucleic acids and transcription factors by cationic liposomes. Liposomes containing the cationic lipid N-[1- (2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium (DOTMA) have been found to mediate the efficient delivery of DNA and RNA into cells by forming a positively charged complex with the nucleic acids. Although the mechanism of delivery is not well understood, DOTMA-containing liposomes have been shown to undergo fusion with negatively charged liposomes s and cells. DOTMA liposomes have also been used to deliver purified transcription factors into cells, mediating the expression of specific genes. Procedures for transfection and delivery of regulatory proteins are described in this chapter. These experiments present that the expression of the transcriptional regulator in bacteria and subsequent biochemical purification does not affect the in vivo activities of the molecule, as shown by endogenous expression in mammalian cells.