Intracellular trafficking of cell-penetrating peptide–avidin complexes

摘要

For any drug or biomolecule to exert its bioactivity, in most cases it needs to enter into cells and migrate to the necessary cellular compartment, where it can interact with its target molecule(s). Unfortunately, a large number of biomolecules are poorly translocating through the lipid bilayer of the plasma membrane making them inefficient and their use problematic. Cell-penetrating peptides (CPPs) are effective transport vectors possessing the ability to facilitate the efficient uptake of various cargos ranging from small peptide sequences to larger biomolecules, such as proteins and nucleotides. Internalization of CPP–cargo complexes depends highly on the nature of the cargo molecule as well as the characteristic properties of the carrier peptide. Most of the cellular uptake occurs via endocytosis, and a large fraction of the internalized CPP–cargo complexes are found inside endocytic vesicles. The intracellular trafficking, final destination and ultimately the fate of these complexes inside the cells are still unclear and currently under intense investigation. In this issue, there are two articles that specifically deal with this issue to provide new insights into more effective targeting of cargo to the desired cellular compartment.