FIGURE 5.

Attenuated apoptotic responses in Has1/3 null fibroblasts involve reduced caspase activation. A, representative Western blots of cleaved caspase-9, cleaved caspase-3, and full-length and cleaved PARP in skin fibroblasts at different times after UVB exposure (32 mJ/cm²). GAPDH was used as a loading control. B, Western blots as in A, from fibroblasts harvested at different times after serum starvation. Data in the table below these blots are the mean from densitometric scans in the corresponding lane, averaged from two independent experiments; the variance was less than 20% of the mean in all cases.