Cover photograph (Copyright © 2006, American Society for Microbiology. All Rights Reserved.): A cell-free assay for the recruitment of Fanconi proteins to replicating chromatin. Sperm chromatin (blue) was added to replicating extracts (yellow) prepared from Xenopus eggs. The DAPI (4′,6′-diamidino-2-phenylindole)-stained chromatin in the figures at left show progressive and synchronous decondensation followed by fully replicated nuclei (from top box to bottom). Chromatin replicated in the extracts was isolated at several time points and assayed for the Fanconi proteins xFANCA (lime) and xFANCD2 (dark green). xFANCA and an activated isoform of xFANCD2 (Ub, monoubiquitin) are dependent on initiation of replication for recruitment to chromatin. (See related article in January 2006, vol. 26: issue 2, p. 425.)