title: Amino-terminal enhancer of split (AES) interacts with the oncoprotein NUP98-HOXA9 and enhances its transforming ability.
abstract: NUP98-HOXA9 is the prototype of NUP98 fusion oncoproteins that cause acute myeloid leukemia. It consists of an N-terminal FG-rich portion of the nucleoporin NUP98 fused to the homeodomain region of the homeobox protein HOXA9, and acts as an aberrant transcription factor. To identify interacting partners of NUP98-HOXA9, we used a cytoplasmic yeast two-hybrid assay to avoid the nonspecific trans-activation that would occur with the traditional yeast two-hybrid assay due to the transactivating properties of NUP98-HOXA9. We identified amino-terminal enhancer of split (AES), a transcriptional regulator of the transducin-like enhancer/Groucho family as a novel interaction partner of NUP98-HOXA9. The interaction was confirmed by in vitro pulldown and co-immunoprecipitation assays and was shown to require the FG repeat region of NUP98-HOXA9. Immunofluorescence analysis showed that AES localizes primarily to the interior of the nucleus. AES also showed a strong interaction with wild-type NUP98. AES augmented the transcriptional activity of NUP98-HOXA9. In the presence of NUP98-HOXA9, AES caused an increase in long-term proliferation of primary human CD34+ cells with a marked increase in the numbers of primitive cells. These effects of AES were not observed in the absence of NUP98-HOXA9. AES knockdown diminished the transcriptional and proliferative effects of NUP98-HOXA9. AES caused a shift away from the erythroid lineage in cells expressing NUP98-HOXA9. These data establish AES as an interacting partner of NUP98-HOXA9 and show that it cooperates with NUP98-HOXA9 in transcriptional regulation and cell transformation.
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
authors.forename: Nayan J
authors.initials: NJ
authors.lastname: Sarma
authors.forename: Nabeel R
authors.initials: NR
authors.lastname: Yaseen
mesh_terms: D018952:Antigens, CD34; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D056970:Co-Repressor Proteins; D055785:Gene Knockdown Techniques; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D020014:K562 Cells; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism*; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques
chemical_list: D018952:Antigens, CD34; D056970:Co-Repressor Proteins; D018398:Homeodomain Proteins; C400441:NUP98-HOXA9 fusion protein, human; D028861:Nuclear Pore Complex Proteins; C465451:Nup98 protein, human; D015514:Oncogene Proteins, Fusion; D012097:Repressor Proteins; C498445:TLE5 protein, human