Separated sub-complexes bind to chromatin but the binding is not RLF-B dependent. A, Demembranated sperm nuclei were incubated for 30 mins in XMcm-depleted extract plus crude RLF-B and combinations of Q1, Q3, and crude RLF-M. Chromatin was then isolated in buffer containing 0.1% NP-40 and was immunoblotted for XMcm3 and XMcm7. B, 6-DMAP chromatin was incubated for 15 mins with combinations of XMcm(3+5), XMcm(2+4+6+7), crude RLF-M and crude RLF-B. Chromatin was then isolated in buffer containing 0.1% NP-40 and immunoblotted for XMcm3 and XMcm7.