Intra-nuclear uptake of Antp and Antp-p21 fusion proteins. Immunofluorescent detection of recombinant proteins administered to cultured cells. On the left, transmission light photographs of SKOV-3 tumour cells incubated with 0.1 mg/ml p21, Antp or Antp-p21 proteins are shown. Trafficking of the proteins is shown in the fluorescent photographs at 30, 60 and 180 min post incubation. Antp and Antp-p21 proteins, contrary to p21, are shown to gradually accumulate in the nucleus of the cells. (1,2) cytoplasm, (3,4) nucleus.