Genome-wide characterization of cis-acting DNA targets of ZmbZIP22 in maize

A new factor binds to the 27-kD ?-zein gene promoter was identified through probe affinity purification and mass spectrometry analysis. This new factor belongs to bZIP type TF (hence named as ZmbZIP22). Chromatin immunoprecipitation coupled to high-throughput sequencing (ChIP-Seq) analysis with two biological replicates was performed to determine the DNA binding targets of ZmbZIP22. ChIP-Seq analysis detected 1,550 DNA binding sites distributed over 514 genes. We identified ACAGCTCA as the most conserved ZmbZIP22 binding motif. We confirmed that ZmbZIP22 binds the 27-kD ?-zein gene promoter in vivo, and also identified additional direct targets of ZmbZIP22. Overall design: Examination of 15 days after pollination (DAP) wild type maize endosperm in duplicate with ZmbZIP22 specific antibody and IgG serves as control.