Structural highlights
Disease
ENL_HUMAN A chromosomal aberration involving MLLT1 is associated with acute leukemias. Translocation t(11;19)(q23;p13.3) with KMT2A/MLL1. The result is a rogue activator protein.
Function
ENL_HUMAN Component of the super elongation complex (SEC), a complex required to increase the catalytic rate of RNA polymerase II transcription by suppressing transient pausing by the polymerase at multiple sites along the DNA.[1] [2]
Publication Abstract from PubMed
Dysfunction of YEATS-domain-containing MLLT1, an acetyl/acyl-lysine dependent epigenetic reader domain, has been implicated in the development of aggressive cancers. Mutations in the YEATS domain have been recently reported as a cause of MLLT1 aberrant reader function. However, the structural basis for the reported alterations in affinity for acetylated/acylated histone has remained elusive. Here, we report the crystal structures of both insertion and substitution mutants present in cancer, revealing significant conformational changes of the YEATS-domain loop 8. Structural comparison demonstrates that not only did such alteration alter the binding interface for acetylated/acylated histones, but the sequence alterations in the loop in T1 mutant may enable dimeric assembly consistent with inducing self-association behavior. Nevertheless, we show that also the MLLT1 mutants can be targeted by developed acetyllysine mimetic inhibitors with affinities similarly to wild-type. Our report provides a structural basis for the altered behaviors and a potential strategy for targeting oncogenic MLLT1 mutants.
Structure and Inhibitor Binding Characterization of Oncogenic MLLT1 Mutants.,Ni X, Londregan AT, Owen DR, Knapp S, Chaikuad A ACS Chem Biol. 2021 Mar 21. doi: 10.1021/acschembio.0c00960. PMID:33749253[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Lin C, Smith ER, Takahashi H, Lai KC, Martin-Brown S, Florens L, Washburn MP, Conaway JW, Conaway RC, Shilatifard A. AFF4, a component of the ELL/P-TEFb elongation complex and a shared subunit of MLL chimeras, can link transcription elongation to leukemia. Mol Cell. 2010 Feb 12;37(3):429-37. doi: 10.1016/j.molcel.2010.01.026. PMID:20159561 doi:10.1016/j.molcel.2010.01.026
- ↑ He N, Liu M, Hsu J, Xue Y, Chou S, Burlingame A, Krogan NJ, Alber T, Zhou Q. HIV-1 Tat and host AFF4 recruit two transcription elongation factors into a bifunctional complex for coordinated activation of HIV-1 transcription. Mol Cell. 2010 May 14;38(3):428-38. doi: 10.1016/j.molcel.2010.04.013. PMID:20471948 doi:10.1016/j.molcel.2010.04.013
- ↑ Ni X, Londregan AT, Owen DR, Knapp S, Chaikuad A. Structure and Inhibitor Binding Characterization of Oncogenic MLLT1 Mutants. ACS Chem Biol. 2021 Mar 21. doi: 10.1021/acschembio.0c00960. PMID:33749253 doi:http://dx.doi.org/10.1021/acschembio.0c00960
