The present invention provides a carrier for the delivery of molecules with biological function into both cellular and nuclear compartments. The carrier disclosed is heat shock protein 70 ("Hsp70"), or a fragment of Hsp70 as described herein, as a vehicle for directed, non-invasive delivery of molecules, such as proteins, peptides, or DNA, that may modulate cellular activity. The present invention also encompasses the use of Hsp70, or a fragment thereof, to modulate cellular activity, preferably to modulate nuclear activity in a cell or cells.
