Genome-wide identification of MYB3R3-bound genes. Arabidopsis thaliana

Arabidopsis genome has 5 genes that encode for R1R2R3-type Myb transcription factors. We showed previously that two R1R2R3-Myb transcriptional factors, MYB3R1 and MYB3R4, bind to cis-acting motifs called MSA, which are commonly present in many G2/M-specific genes and act as transcriptional activator. Here, we performed genome-wide approach to identify target genes of MYB3R3, which, together with MYB3R1 and MYB3R5, have potential functions in transcriptional repression of G2/M-specific genes. Our ChIP-seq analysis revealed that MYB3R3 preferentially binds to the G2/M-specific genes in vivo. In addition, our data also showed that MYB3R3 associates with the predicted target genes of E2F, well known transcription factors acting during G1/S. These results suggested that MYB3R3 may not only directly bind G2/M-specific genes though recognition of the MSA elements, but also indirectly associates with DNA replication genes through physical interaction with E2F. Overall design: Chromatin immunoprecipitation was performed with MYB3R3-GFP-expressing Arabidopsis. ChIPed and input DNA from MYB3R3-GFP plants were subjected to Next-generation sequencing.