Figure 3. Using the age calculator to determine the biological age of progeroid Ercc1-/Δ mice. (A) Expression of the 14 proteins selected for the biological age calculator in male f1 Ercc1-/Δ mouse liver (hatched bars) compared to age-matched f1 male mice (solid red) at 3 ages. The proteins with blue titles decreased significantly in expression with chronological age of wild-type mice, while those with red titles increased significantly with aging in WT mice (