title: The eleven-nineteen-leukemia protein ENL connects nuclear MLL fusion partners with chromatin.
abstract: Mixed lineage leukemia (MLL) fusion proteins are derived from translocations at 11q23 that occur in aggressive subtypes of leukemia. As a consequence, MLL is joined to different unrelated proteins to form oncogenic transcription factors. Here we demonstrate a direct interaction between several nuclear MLL fusion partners and present evidence for a role of these proteins in histone binding. In two-hybrid studies, ENL interacted with AF4 and AF5q31 as well as with a fragment of AF10. A structure-function analysis revealed that the AF4/AF5q31/AF10 binding domain in ENL coincided with the C-terminus that is essential for transformation by MLL-ENL. The ENL/AF4 association was corroborated by GST-pulldown experiments and by mutual coprecipitation. Both proteins colocalized in vivo in a nuclear speckled pattern. Moreover, AF4 and ENL coeluted on sizing columns together with the known ENL binding partner Polycomb3, suggesting the presence of a multiprotein complex. The overexpression of ENL alone activated a reporter construct and a mutational screen indicated the conserved YEATS domain as essential for this function. Overlay and pulldown-assays finally showed a specific and YEATS domain-dependent association of ENL with histones H3 and H1. In summary, our studies support a common role for nuclear MLL fusion partners in chromatin biology.
authors.affiliation: Department of Genetics, University Erlangen, Staudtstrasse 5, 91058 Erlangen, Germany.
authors.forename: Deniz T
authors.initials: DT
authors.lastname: Zeisig
authors.forename: Claudia B
authors.initials: CB
authors.lastname: Bittner
authors.forename: Bernd B
authors.initials: BB
authors.lastname: Zeisig
authors.forename: Maria-Paz
authors.initials: MP
authors.lastname: García-Cuéllar
authors.forename: Jay L
authors.initials: JL
authors.lastname: Hess
authors.forename: Robert K
authors.initials: RK
authors.lastname: Slany
mesh_terms: D000818:Animals; D002843:Chromatin / Q000737:chemistry / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011495:Histone-Lysine N-Methyltransferase; D006657:Histones / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D051788:Myeloid-Lymphoid Leukemia Protein; D014176:Protein Biosynthesis / Q000502:physiology*; D011519:Proto-Oncogenes; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D006657:Histones; C497422:KMT2A protein, human; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase