Figure 3. Smc3 acetylation and replication fork progression are interdependent.

a and b, Karyotypic analysis of E6- and E7-expressing DCC1^+/Δ and DCC1^Δ/Δ cells. Chromatid gaps (arrowhead), triradial (tr), and quadriradial (qr) chromosomes are highlighted. c, Cells in (a) were synchronized in S phase with thymidine. Chromatin-associated Smc3 was immunopurified and blotted for acetylated lysine or total Smc3. Wildtype (WT) and non-acetylatable (AA) Smc3 variants⁸ were included as controls. d, Soluble and chromatin fractions from S-phase cells were analyzed by immunoblotting. e, Fork velocities were determined in cells from normal donors and RBS patients, and in cells expressing Smc3^WT or Smc3^AA from a doxycycline-inducible promoter.