FIG. 4.

A gradual decrease of HCMV protease expression correlates with distinct stimulation of cell proliferation. In the first four columns, RLY07 cells were cotransformed with Trp1¹⁹⁴-Me and with active HCMV protease expressed from a GAL1 promoter series (see Materials and Methods for detailed information). The last column shows cell growth mediated by the inactive protease. Cell densities were monitored after 30 h by measuring OD₅₉₅. Data are expressed as means from three independent experiments ± standard deviations.