Lysine butyrylation (Kbu) is a novel PTM that is found in histone and nonhistone proteins8. Kbu has been identified in fungi, plants and animals9,10,11, but a global landscape of nonhistone protein Kbu modification in humans is lacking. More importantly, the writer and eraser responsible for Kbu deposition and removal in humans, respectively, have not been reported.

Reference
Pubmed: He Y, Zheng CC, Yang J, Li SJ, Xu TY, Wei X, Chen WY, Jiang ZL, Xu JJ, Zhang GG, Cheng C, Chen KS, Shi XY, Qin DJ, Liu JB, Li B. Lysine butyrylation of HSP90 regulated by KAT8 and HDAC11 confers chemoresistance. Cell Discov. 2023 Jul 18;9(1):74. doi: 10.1038/s41421-023-00570-y.