FIGURE 2.

Absence of PTEN expression confers susceptibility of cells to Mycoplasma infection. A, PTEN-null cells are prone to infection by Mycoplasma. PTEN-positive cells (wild-type MEFs and HeLa cells) and PTEN-null cells (pten^−/− MEFs and PC3 cells) were infected with culture medium containing Mycoplasma and then tested by DAPI staining as described under “Experimental Procedures.“ B, pten^−/− MEF cells were infected by Mycoplasma more quickly than the wild-type counterpart. Both pten^−/− and wild-type MEFs were infected with Mycoplasma. Infection was followed by DAPI staining at the indicated time points. C, infection was also detected by PCR using primers specific for M. orale. D, Western blot shows the effect of knockdown of PTEN by shRNA (iPTEN) in HeLa cells. LacZ shRNA (iLacZ) was used as negative control. A PCAF blot serves as the loading control. E, PTEN knockdown but not control knockdown makes HeLa Mycoplasma infection-prone. Mycoplasma infection was monitored by DAPI staining. Scale bar = 20 μm.