Nuclear targeting of macromolecular polyanions by an HIV-Tat derived peptide: role for cell-surface proteoglycans.
New therapies, based on gene transfer and protein delivery, require a better understanding of the basic mechanisms of macromolecular membrane transport. We have studied cellular uptake of macromolecular polyanions, i.e. DNA and glycosaminoglycans, and a polybasic HIV-Tat derived peptide (GRKKRRQRRRPPQC), using fluorescence assisted cell sorting and confocal fluorescence microscopy. The Tat peptide