- Lutterbach B, Westendorf JJ, Linggi B, Isaac S, Seto E, Hiebert SW. A mechanism of repression by acute myeloid leukemia-1, the target of multiple chromosomal translocations in acute leukemia. The Journal of biological chemistry. 2000 Jan 7;275(1). 651-6. PMID: 10617663 [PubMed].
AML1 is one of the most frequently translocated genes in human leukemia. Here we demonstrate that acute myeloid leukemia-1 (AML-1) (Runx-1) represses transcription from a native promoter, p21(Waf1/Cip1). Unexpectedly, this repression did not require interactions with the Groucho co-repressor. To define the mechanism of repression, we asked whether other co-repressors could interact with AML-1. We demonstrate that AML-1 interacts with the mSin3 co-repressors. Moreover, endogenous AML-1 associated with endogenous mSin3A in mammalian cells. A deletion mutant of AML-1 that did not interact with mSin3A failed to repress transcription. The AML-1/mSin3 association suggests a mechanism of repression for the chromosomal translocation fusion proteins that disrupt AML-1.