show Abstracthide AbstractHistone acetylation, a post-translational modification associated with transcriptional activation, is governed by nuclear acetyl-CoA pools that can vary depending on the metabolic state of the cell. The metabolic enzyme acetyl-CoA synthetase 2 (ACSS2) is proposed to regulate nuclear acetyl-CoA levels, using local acetate to produce acetyl-CoA that is utilized for histone acetylation. We hypothesize that during gene activation, a local transfer of intact acetate occurs between histones to upregulate transcription via sequential action of epigenetic and metabolic enzymes. Here we present converging lines of evidence in support of this acetate transfer to serve rapid gene induction. Using stable isotope labeling, we detect local transfer of intact acetate between histone acetylation sites both in vitro using purified mammalian enzymes and in vivo using quiescence exit in Saccharomyces cerevisiae as a change-of-state model. We delineate the enzymatic components required for this transfer mechanism, finding that ACSS2, histone deacetylase and histone acetyltransferase enzymes are necessary for efficient acetyl-group transfer in vitro. We show that Acs2, the yeast orthologue of ACSS2, is recruited to the genome during quiescence exit, and observe dynamic changes of histone acetylation in the vicinity of Acs2 peaks in vivo. Strikingly, we find that Acs2 is preferentially associated with the most upregulated growth genes, suggesting that acetyl-group transfer might play an important role in increased gene expression. Overall, our data reveal direct transfer of acetate between histone lysine residues to facilitate rapid transcriptional induction, an exchange that may be critical during metabolic alterations and changes in nutrient availability. Overall design: ChIP-seq in a time-course in S. cerevisiae during quiescence exit, measuring four histone acetylation post-translational modifications (H3K9ac, H3K18ac, H3K23ac, and H3K27ac) as well as the enzyme ACSS2; ACSS2 is also measured using TAP-tag in a second strain of yeast. Four time points are measured: glucose-deprived quiescent cells (Q), 30 min post-quiescence exit (E30), 240 min post-quiescence exit (E240), and logarithmic growth (LOG). The replicate structure is as follows: H3K9ac, H3K18ac, H3K23ac, H3K27ac and non-tagged ACSS2 have two replicates each in each time point, with a corresponding two replicates of input in each time point to adjust for sonication efficiency bias; while TAP-tagged ACSS2 has two replicates in Q and E30 and one sample in E240 and LOG, with a corresponding input from this strain with identical replicate structure.