Figure 4
From: Non-canonical protein-DNA interactions identified by ChIP are not artifacts
ChIP/qPCR of AraC using the standard method with or without Spin-X columns. ChIP/qPCR measurement of AraC association with six known AraC target regions for cells grown in the absence of arabinose. Data are shown for ChIP performed without Spin-X columns (light gray bars) or with Spin-X columns (dark gray bars). Note that the region upstream of ydeN is only bound by AraC in the presence of arabinose and hence serves as a control in this experiment. Occupancy units represent background-subtracted enrichment of target regions relative to a control region. Error bars represent the standard deviation from three independent biological replicates. Note that data for ChIP/qPCR using Spin-X columns (dark gray bars) will be described elsewhere (Stringer, A.M., Currenti, S.A., Bonocora, R.P., Baranowski, C., Petrone, B.L., Singh, N., Palumbo, M.J., Reilly, A.E., Zhang, Z., Erill, I. and Wade, J.T.: Comprehensive genomic analysis of the Escherichia coli and Salmonella enterica AraC regulons; in preparation) and serve only as a reference for data from ChIP/qPCR without Spin-X columns.