title: IKAROS: a multifunctional regulator of the polymerase II transcription cycle.
abstract: Transcription factors are important determinants of lineage specification during hematopoiesis. They favor recruitment of cofactors involved in epigenetic regulation, thereby defining patterns of gene expression in a development- and lineage-specific manner. Additionally, transcription factors can facilitate transcription preinitiation complex (PIC) formation and assembly on chromatin. Interestingly, a few lineage-specific transcription factors, including IKAROS, also regulate transcription elongation. IKAROS is a tumor suppressor frequently inactivated in leukemia and associated with a poor prognosis. It forms a complex with the nucleosome remodeling and deacetylase (NuRD) complex and the positive transcription elongation factor b (P-TEFb), which is required for productive transcription elongation. It has also been reported that IKAROS interacts with factors involved in transcription termination. Here we review these and other recent findings that establish IKAROS as the first transcription factor found to act as a multifunctional regulator of the transcription cycle in hematopoietic cells.
authors.affiliation: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada.
authors.forename: Stefania
authors.initials: S
authors.lastname: Bottardi
authors.affiliation: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada.
authors.forename: Lionel
authors.initials: L
authors.lastname: Mavoungou
authors.affiliation: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada. Electronic address: e.milot.1@umontreal.ca.
authors.forename: Eric
authors.initials: E
authors.lastname: Milot
mesh_terms: D000818:Animals; D042002:Chromatin Assembly and Disassembly; D004257:DNA Polymerase II / Q000502:physiology*; D005786:Gene Expression Regulation; D006801:Humans; D051740:Ikaros Transcription Factor / Q000502:physiology*; D014158:Transcription, Genetic
chemical_list: D051740:Ikaros Transcription Factor; D004257:DNA Polymerase II
keywords: IKAROS; NuRD; P-TEFb; hematopoiesis; transcription elongation; transcription termination