FIGURE 4.
Standing start assays for replication bypass of DNA-peptide and DNA-protein cross-links by hPol η. 9-mer FAMdT primers were annealed with 20-mers containing unmodified dG (A), deaza-DHP-dG (B), or covalent cross-links to 10-mer peptide EQKLISEEDL (C), 23-mer peptide PDAQLVPGINGKAIHLVNNESSE (D), or full-sized protein AlkB (E), histone (His) H4 (F), or eGFP (G). The resulting primer-template duplexes (0.15 μm) were incubated in the presence of hPol η (0.30 μm). Reactions were initiated by the addition of a mixture of dNTPs (500 μm) and quenched at the indicated time points. Extension products were separated by 20% denaturing PAGE and visualized by fluorescence imaging. Panel H shows results for DPC to histone (His) H4 following digestion with Proteinase K.