Abstract
Activating signal cointegrator-2 (ASC-2), a coactivator of multiple transcription factors that include retinoic acid receptor (RAR), associates with histone H3-K4 methyltranferases (H3K4MTs) MLL3 and MLL4 in mixed-lineage leukemia. Here, we show that mice expressing a SET domain mutant of MLL3 share phenotypes with isogenic ASC2+/- mice and that expression and H3-K4 trimethylation of RAR target gene RAR-beta2 are impaired in ASC-2-null mouse embryo fibroblasts (MEFs) or in MEFs expressing siRNAs against both MLL3 and MLL4. We also show that MLL3 and MLL4 are found in distinct ASC-2-containing complexes rather than in a common ASC-2 complex, and they are recruited to RAR-beta2 by ASC-2. In contrast, RAR-beta2 expression is intact in MEFs devoid of menin, a component of MLL1 and MLL2 H3K4MT complexes. These results suggest that ASC-2 confers target gene specificity to MLL3 and MLL4 H3K4MT complexes and that recruitment of H3K4MTs to their target genes generally involves interactions between integral components of H3K4MT complexes and transcription factors.
Publication types
-
Research Support, N.I.H., Extramural
MeSH terms
-
Animals
-
Cells, Cultured
-
Fibroblasts / cytology
-
Fibroblasts / metabolism
-
Gene Expression Regulation*
-
Genes, Tumor Suppressor
-
Histone-Lysine N-Methyltransferase / genetics
-
Histone-Lysine N-Methyltransferase / metabolism*
-
Humans
-
Intracellular Signaling Peptides and Proteins / genetics
-
Intracellular Signaling Peptides and Proteins / metabolism*
-
Macromolecular Substances
-
Methylation
-
Mice
-
Nuclear Receptor Coactivators
-
Phenotype
-
Proto-Oncogene Proteins / genetics
-
Proto-Oncogene Proteins / metabolism
-
RNA, Small Interfering / genetics
-
RNA, Small Interfering / metabolism
-
Receptors, Retinoic Acid / genetics
-
Receptors, Retinoic Acid / metabolism
-
Transcription Factors / metabolism
Substances
-
Intracellular Signaling Peptides and Proteins
-
Macromolecular Substances
-
Men1 protein, mouse
-
Ncoa6 protein, mouse
-
Nuclear Receptor Coactivators
-
Proto-Oncogene Proteins
-
RNA, Small Interfering
-
Receptors, Retinoic Acid
-
Transcription Factors
-
retinoic acid receptor beta
-
Histone-Lysine N-Methyltransferase
-
MLL3 protein, mouse
-
MLL4 protein, mouse