Neuronal Differentiation of Neural Progenitor Cells by Intracellular Delivery of Synthetic Oligopeptide Derived from Von Hippel-Lindau Protein

Intracellular delivery of synthetic oligopeptides has the potential to promote the occurrence of various cellular events such as cell death, proliferation, growth inhibition, metabolic changes, and morphological changes. However, the regulation of cellular differentiation by intracellular delivery of synthetic oligopeptides has been little studied. Von Hippel- Lindau protein (pVHL) is one of the proteins that functions to induce the differentiation of neural progenitor cells (NPCs). To function in these cells, pVHL forms a complex composed of itself, elongin BC, Clu-2, and Rbx-1. It is suggested that the binding site of elongin BC in pVHL plays a critical role in pVHL function, i.e., ubiquitination, which is related to neuronal differentiation. So, we synthesized an oligopeptide corresponding to the elongin BC binding site, and delivered the oligopeptide into NPCs by using a mixture of trifluoroacetylated lipopolyamine and diloeoyl phosphatidylethanolamine (BioPorter) to form a peptide-lipid complex. After intracellular delivery of the oligopeptide, induction of differentiation of NPCs was shown in terms of neurite outgrowth and by immunocytochemical and electrophysiological means. The intracellular delivery of the synthetic oligopeptide derived from pVHL may provide a safe and valuable approach for the neuronal differentiation of NPCs.