| Co transfection of Hsp 70 with its co chaperone human DnaJ homologue ( Hdj ) 1 / Hsp40 , however , stabilizes the immature form of wt CFTR , but not of F508del CFTR , suggesting that these chaperones act on a wt specific conformation . ^^^ The human DnaJ homologue ( Hdj ) 1 / heat shock protein ( Hsp ) 40 co chaperone is required for the in vivo stabilization of the cystic fibrosis transmembrane conductance regulator by Hsp 70 . ^^^ |