TY - UNPB
T1 - αKG-mediated carnitine synthesis promotes homologous recombination via histone acetylation
AU - Uboveja, Apoorva
AU - Huang, Zhentai
AU - Buj, Raquel
AU - Amalric, Amandine
AU - Wang, Hui
AU - Tangudu, Naveen Kumar
AU - Cole, Aidan R
AU - Megill, Emily
AU - Kantner, Daniel
AU - Chatoff, Adam
AU - Ahmad, Hafsah
AU - Marcinkiewicz, Mariola M
AU - Disharoon, Julie A
AU - Graff, Sarah
AU - Dahl, Erika S
AU - Hempel, Nadine
AU - Stallaert, Wayne
AU - Sidoli, Simone
AU - Bitler, Benjamin G
AU - Long, David T
AU - Snyder, Nathaniel W
AU - Aird, Katherine M
PY - 2024/2/11
Y1 - 2024/2/11
N2 - Homologous recombination (HR) deficiency enhances sensitivity to DNA damaging agents commonly used to treat cancer. In HR-proficient cancers, metabolic mechanisms driving response or resistance to DNA damaging agents remain unclear. Here we identified that depletion of alpha-ketoglutarate (αKG) sensitizes HR-proficient cells to DNA damaging agents by metabolic regulation of histone acetylation. αKG is required for the activity of αKG-dependent dioxygenases (αKGDDs), and prior work has shown that changes in αKGDD affect demethylases. Using a targeted CRISPR knockout library consisting of 64 αKGDDs, we discovered that Trimethyllysine Hydroxylase Epsilon (TMLHE), the first and rate-limiting enzyme in de novo carnitine synthesis, is necessary for proliferation of HR-proficient cells in the presence of DNA damaging agents. Unexpectedly, αKG-mediated TMLHE-dependent carnitine synthesis was required for histone acetylation, while histone methylation was affected but dispensable. The increase in histone acetylation via αKG-dependent carnitine synthesis promoted HR-mediated DNA repair through site- and substrate-specific histone acetylation. These data demonstrate for the first time that HR-proficiency is mediated through αKG directly influencing histone acetylation via carnitine synthesis and provide a metabolic avenue to induce HR-deficiency and sensitivity to DNA damaging agents.
AB - Homologous recombination (HR) deficiency enhances sensitivity to DNA damaging agents commonly used to treat cancer. In HR-proficient cancers, metabolic mechanisms driving response or resistance to DNA damaging agents remain unclear. Here we identified that depletion of alpha-ketoglutarate (αKG) sensitizes HR-proficient cells to DNA damaging agents by metabolic regulation of histone acetylation. αKG is required for the activity of αKG-dependent dioxygenases (αKGDDs), and prior work has shown that changes in αKGDD affect demethylases. Using a targeted CRISPR knockout library consisting of 64 αKGDDs, we discovered that Trimethyllysine Hydroxylase Epsilon (TMLHE), the first and rate-limiting enzyme in de novo carnitine synthesis, is necessary for proliferation of HR-proficient cells in the presence of DNA damaging agents. Unexpectedly, αKG-mediated TMLHE-dependent carnitine synthesis was required for histone acetylation, while histone methylation was affected but dispensable. The increase in histone acetylation via αKG-dependent carnitine synthesis promoted HR-mediated DNA repair through site- and substrate-specific histone acetylation. These data demonstrate for the first time that HR-proficiency is mediated through αKG directly influencing histone acetylation via carnitine synthesis and provide a metabolic avenue to induce HR-deficiency and sensitivity to DNA damaging agents.
U2 - 10.1101/2024.02.06.578742
DO - 10.1101/2024.02.06.578742
M3 - Preprint
C2 - 38370789
T3 - bioRxiv
BT - αKG-mediated carnitine synthesis promotes homologous recombination via histone acetylation
ER -