The AF4/AF4-MLL interactome

Introduction: We have recently unraveled the composition of the human AF4 and AF4-MLL protein complex by combining recombinant expression in human cells with state-of-the art-biochemical and mass spectrometry methods (Benedikt et al., 2011). Functional studies have revealed the functions of both complexes. The AF4 complex is necessarily involved in the activation of RNA polymerase II for transcriptional elongation. For this purpose, kinase activity of the associated P-TEFb complex and certain histon methyltransferase activities are required. The AF4-MLL fusion protein complex merges critical properties of the hu…