Global analysis of in vivo EGR1-binding sites in erythroleukemia cell K562 using chromatin immunoprecipitation and massively parallel sequencing

Early growth response gene 1 (EGR1) has been implicated in megakaryocyte differentiation induced by PMA (phorbol 12-myristate 13-acetate). The identification of direct EGR1 target genes in global scale is critical for our understanding of how EGR1 contributes to this process. In this study, we provide a global survey on the binding location of EGR1 in the K562 cell treated by PMA using chromatin immunoprecipitation and massively parallel sequencing (ChIP-Seq). K562 is a human erythroleukemia cell line, which is situated in the common progenitor stage of megakaryocytic and erythroid lineages of the hematopoietic stem cell differentiation and its normally following differentiation is blockaded. Upon exposure to PMA stimuli, K562 cell can be induced into megakaryocytic cell, which provides a model for the study of transcriptional control networks. Over 14 000 highly confident in vivo EGR1 binding sites were identified in PMA treated K562 cell. More than 70% of these genomic sites associated with EGR1 binding were located around annotated gene regions. This whole genome study on the EGR1 targets may help a better understanding of the EGR1 regulated genes and the downstream pathway in megakaryocyte differentiation.