Life Sciences Commons^™

The Hiv-1 Tat Protein Is Monomethylated At Lysine 71 By The Lysine Methyltransferase Kmt7, Ibraheem Ali, Holly Ramage, Daniela Boehm, Lynnette M. A. Dirk, Naoki Sakane, Kazuki Hanada, Sara Pagans, Katrin Kaehlcke, Katherine Aull, Leor Weinberger, Raymond Trievel, Martina Schnoelzer, Masafumi Kamada, Robert L. Houtz, Melanie Ott

Horticulture Faculty Publications

The HIV-1 transactivator protein Tat is a critical regulator of HIV transcription primarily enabling efficient elongation of viral transcripts. Its interactions with RNA and various host factors are regulated by ordered, transient post-translational modifications. Here, we report a novel Tat modification, monomethylation at lysine 71 (K71). We found that Lys-71 monomethylation (K71me) is catalyzed by KMT7, a methyltransferase that also targets lysine 51 (K51) in Tat. Using mass spectrometry, in vitro enzymology, and modification-specific antibodies, we found that KMT7 monomethylates both Lys-71 and Lys-51 in Tat. K71me is important for full Tat transactivation, as KMT7 knockdown impaired the transcriptional activity …