by coupling the natural iron-delivery protein transferrin to the dna-binding polycations polylysine or protamine , we have created protein conjugates that bind nucleic acids and carry them into the cell during the normal transferrin cycle [ wagner , e. , zenke , m. , cotten , m. , beug , h. & birnstiel , m. l. ( 1990 ) proc . natl . acad . sci . usa 87 , 3410-3414 ] .
C0012940
protein
C0033684
protein