Fig. 1.

Regulation of sororin recruitment to chromatin by the cohesin complex and DNA replication. (A) Sororin depends on cohesin for association with chromatin. Nuclear assembly reactions were set up in extract that had been depleted of cohesin (ΔSmc3), sororin (Δsororin), or mock-depleted (mock), and chromatin was isolated at the indicated time points and assayed for cohesin (Smc3) and sororin by immunoblot. Control: background band used as loading control. (B) Sororin recruitment requires DNA replication. Sperm nuclei were added to interphase extract supplemented with geminin, p27, aphidicolin, or a buffer control (mock). At the indicated times, chromatin was isolated and analyzed by immunoblot for the presence of cohesin (Smc3) and sororin. (C) DNA replication assay of the same samples shown in B. All three inhibitors effectively blocked DNA replication. Coomassie stained histones were used as a loading control (Lower).