PT  - JOURNAL ARTICLE
AU  - Paula A. Agudelo Garcia
AU  - Prabakaran Nagarajan
AU  - Mark R. Parthun
TI  - Hat1-Dependent Lysine Acetylation Targets Diverse Cellular Functions
AID  - 10.1101/825539
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 825539
4099  - http://biorxiv.org/content/early/2019/12/10/825539.short
4100  - http://biorxiv.org/content/early/2019/12/10/825539.full
AB  - Lysine acetylation has emerged as one of the most important post-translational modifications, regulating different biological processes. However, its regulation by lysine acetyltransferases is still unclear in most cases. Hat1 is a lysine acetyltransferase originally identified based on its ability to acetylate histones. Using an unbiased proteomics approach, we have determined how loss of Hat1 affects the mammalian acetylome. Hat1+/+ and Hat1−/− mouse embryonic fibroblast (MEF) cells lines were grown in both glucose- and galactose-containing media, as Hat1 is required for growth on galactose and Hat1−/− cells exhibit defects in mitochondrial function. Following trypsin digestion of whole cell extracts, acetylated peptides were enriched by acetyllysine affinity purification and acetylated peptides were identified and analyzed by label-free quantitation. Comparison of the acetylome from Hat1+/+ cells grown on galactose and glucose demonstrated that there are large carbon source-dependent changes in the mammalian acetylome where the acetylation of enzymes involved in glycolysis was the most affected. Comparisons of the acetylomes from Hat1+/+ and Hat1−/− cells identified 65 proteins whose acetylation decreased by at least 2.5-fold in cells lacking Hat1. In Hat1−/− cells, acetylation of the auto regulatory loop of CBP was the most highly affected, decreasing by up to 20-fold. In addition to proteins involved in chromatin structure, Hat1-dependent acetylation was also found in a number of transcriptional regulators, including p53, and mitochondrial proteins. Hat1 mitochondrial localization suggests that it may be directly involved in the acetylation of mitochondrial proteins.