RESUMO
We have previously characterised the histone lysine methyltransferase properties of PRDM9, a member of the PRDM family of putative transcriptional regulators. PRDM9 displays broad substrate recognition and methylates a range of histone substrates, including octamers, core histone proteins, and peptides. In the present study, we show that PRDM9 performs intramolecular automethylation on multiple lysine residues localised to a lysine-rich region on the post-SET (suppressor of variegation 3-9, enhancer of zeste and trithorax) domain. PRDM9 automethylation is abolished by a single active-site mutation, C321P, also known to disrupt interactions with S-adenosylmethionine. We have taken an initial step towards tool compound generation through rational design of a substrate-mimic, peptidic inhibitor of PRDM9 automethylation. The discovery of automethylation in PRDM9 adds a new dimension to our understanding of PRDM9 enzymology.
Assuntos
Cisteína/química , Histona-Lisina N-Metiltransferase/química , Prolina/química , Processamento de Proteína Pós-Traducional , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Domínio Catalítico , Clonagem Molecular , Cisteína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Cinética , Ligantes , Metilação , Camundongos , Modelos Moleculares , Mutação , Prolina/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
[This corrects the article DOI: 10.1021/acsmedchemlett.9b00170.].
RESUMO
SMYD3 is a histone methyltransferase that regulates gene transcription, and its overexpression is associated with multiple human cancers. A novel class of tetrahydroacridine compounds which inhibit SMYD3 through a covalent mechanism of action is identified. Optimization of these irreversible inhibitors resulted in the discovery of 4-chloroquinolines, a new class of covalent warheads. Tool compound 29 exhibits high potency by inhibiting SMYD3's enzymatic activity and showing antiproliferative activity against HepG2 in 3D cell culture. Our findings suggest that covalent inhibition of SMYD3 may have an impact on SMYD3 biology by affecting expression levels, and this warrants further exploration.