Figure 3.

Effect of ANAPC1 Deficiency and Cell Cycle Variations of RECQL4

(A) Fibroblasts derived from individuals homozygous for the ANAPC1 intronic variant spent a longer time at the interphase of the cell cycle compared to control fibroblasts (^∗∗∗ = p < 0.001); the time-lapse microscopy was performed as described previously.²⁶ The middle line represents the median, the box represents quartiles, and the whiskers represent minimum and maximum values within 1.5 times the interquartile range.

(B) Proteins from thymidine-nocodazole-synchronized-MG132-treated and non-treated HeLa cells at specific time points (0 to 8 hours) were analyzed by SDS-PAGE and immunoblot. The upward-shifted (phospho) APC3 represents a marker for mitosis. The cyclin B disappearance represents a positive control for APC/C activity, and actin is used as a loading control. RECQL4 protein levels decreased within the first 3 h of mitosis and became stable after treatment with MG132, similar to classical APC/C substrates such as cyclin B. Asyn signifies asynchronous cells.

(C) Mice heterozygous for a loss-of-function Anapc1 mutation develop cataracts more frequently than wild-type mice (detailed data: no lens opacity in 2,766 WT (wild-type) mice and 12 het (heterozygous KO) mice, lens opacity in one eye in 116 WT mice and 4 het mice, lens opacities in both eyes in 17 WT mice and no het mice).