Involved in chromatin organization. Found in a mRNA splicing-dependent exon junction complex (EJC) with DEK, RBM8A, RNPS1, SRRM1 and ALYREF/THOC4. Interacts with histones H2A, H2B, H3, H4, acetylated histone H4, non-phosphorylated DAXX and HDAC2. Component of the B-WICH complex, at least composed of SMARCA5/SNF2H, BAZ1B/WSTF, SF3B1, DEK, MYO1C, ERCC6, MYBBP1A and DDX21. Binds DNA. Enriched in regions where chromatin is decondensed or sparse in the interphase nuclei. Ubiquitous. Expressed at relatively high levels. Phosphorylated by CK2. Phosphorylation fluctuates during the cell cycle with a moderate peak during G(1) phase, and weakens the binding of DEK to DNA. A chromosomal aberration involving DEK is found in a subset of acute myeloid leukemia (AML); also known as acute non-lymphocytic leukemia (PubMed:1549122). Translocation t(6;9)(p23;q34) with NUP214/CAN (PubMed:1549122). It results in the formation of a DEK-NUP214 fusion gene (PubMed:1549122).