Methylation of the transcription factor E2F1 by SETD6 regulates SETD6 expression via a positive feedback mechanism

Margarita Kublanovsky; Gizem T Ulu; Sara Weirich; Nurit Levy; Michal Feldman; Albert Jeltsch; Dan Levy

doi:10.1016/j.jbc.2023.105236

Methylation of the transcription factor E2F1 by SETD6 regulates SETD6 expression via a positive feedback mechanism

J Biol Chem. 2023 Oct;299(10):105236. doi: 10.1016/j.jbc.2023.105236. Epub 2023 Sep 9.

Authors

Margarita Kublanovsky¹, Gizem T Ulu², Sara Weirich², Nurit Levy¹, Michal Feldman¹, Albert Jeltsch³, Dan Levy⁴

Affiliations

¹ The Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev, Be'er-Sheva, Israel; The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be'er-Sheva, Israel.
² Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany.
³ Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany. Electronic address: albert.jeltsch@ibtb.uni-stuttgart.de.
⁴ The Shraga Segal Department of Microbiology, Immunology and Genetics, Ben-Gurion University of the Negev, Be'er-Sheva, Israel; The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be'er-Sheva, Israel. Electronic address: ledan@post.bgu.ac.il.

Abstract

The protein lysine methyltransferase SET domain-containing protein 6 (SETD6) has been shown to influence different cellular activities and to be critically involved in the regulation of diverse developmental and pathological processes. However, the upstream signals that regulate the mRNA expression of SETD6 are not known. Bioinformatic analysis revealed that the SETD6 promoter has a binding site for the transcription factor E2F1. Using various experimental approaches, we show that E2F1 binds to the SETD6 promoter and regulates SETD6 mRNA expression. Our further observation that this phenomenon is SETD6 dependent suggested that SETD6 and E2F1 are linked. We next demonstrate that SETD6 monomethylates E2F1 specifically at K117 in vitro and in cells. Finally, we show that E2F1 methylation at K117 positively regulates the expression level of SETD6 mRNA. Depletion of SETD6 or overexpression of E2F1 K117R mutant, which cannot be methylated by SETD6, reverses the effect. Taken together, our data provide evidence for a positive feedback mechanism, which regulates the expression of SETD6 by E2F1 in a SETD6 methylation-dependent manner, and highlight the importance of protein lysine methyltransferases and lysine methylation signaling in the regulation of gene transcription.

Keywords: E2F1; SETD6; lysine methylation; protein lysine methylation.