Fig. 1.

ARF in transformed bc1051 (PyMT + PyST) REF52 cells is located in the nucleolus. (A) On the left is shown a photomicrograph of untransformed REF52 cells that contain a normal morphology and are highly contact inhibited. On the right are shown REF52 cells (bc1051 REF52) transformed by the bc1051 polyoma mutant that only expresses PyMT and PyST (22). The bc1051 REF52 cells have a transformed morphology and are not contact inhibited. (B) The location of the Py T-antigens and ARF in transformed bc1051 REF52 cells were analyzed by immunofluorescence staining. On the left, the membrane-bound PyMT and nuclear and cytoplasmic small T-antigen were detected with 762 anti-polyoma common region antibody (Py) and are stained in green (FITC). On the right, ARF found located in the nucleoli was detected with 821B6 antibody and stained in red (Texas red).