Figure 3. Schematic diagram. Proposed model of the influence of HSP27 on ubiquitination and proteasomal degradation of p27^Kip1. In response to a stress, p27^Kip1 translocates from the nucleus to the cytosol. HSP27 interacts with p27^Kip1 and favors its ubiquitination and degradation. This effect favors the progression from the G₀-/G₁-phase to the S-phase of the cell cycle.