Abstract: The present invention provides a method of treating cystic fibrosis in a human subject diagnosed with cystic fibrosis, comprising administering to the subject, in a pharmaceutically acceptable carrier, an effective amount of a fusion protein, comprising a cystic fibrosis transmembrane conductance regulator (CFTR) and a membrane translocation sequence (MST), whereby the fusion protein can be taken up by affected cells in the subject, thereby treating cystic fibrosis. The present invention also provides a fusion protein comprising a cystic fibrosis transmembrane conductance regulator and a membrane translocation sequence.