TY - JOUR
T1 - Nonenzymatic Protein Acetylation Detected by NAPPA Protein Arrays
AU - Olia, Adam S.
AU - Barker, Kristi
AU - McCullough, Cheryl E.
AU - Tang, Hsin Yao
AU - Speicher, David W.
AU - Qiu, Ji
AU - LaBaer, Joshua
AU - Marmorstein, Ronen
N1 - Publisher Copyright:
© 2015 American Chemical Society.
PY - 2015/9/18
Y1 - 2015/9/18
N2 - Acetylation is a post-translational modification that occurs on thousands of proteins located in many cellular organelles. This process mediates many protein functions and modulates diverse biological processes. In mammalian cells, where acetyl-CoA is the primary acetyl donor, acetylation in the mitochondria is thought to occur by chemical means due to the relatively high concentration of acetyl-CoA located in this organelle. In contrast, acetylation outside of the mitochondria is thought to be mediated predominantly by acetyltransferase enzymes. Here, we address the possibility that nonenzymatic chemical acetylation outside of the mitochondria may be more common than previously appreciated. We employed the Nucleic Acid Programmable Protein Array platform to perform an unbiased screen for human proteins that undergo chemical acetylation, which resulted in the identification of a multitude of proteins with diverse functions and cellular localization. Mass spectrometry analysis revealed that basic residues typically precede the acetylated lysine in the -7 to -3 position, and we show by mutagenesis that these basic residues contribute to chemical acetylation capacity. We propose that these basic residues lower the pKa of the substrate lysine for efficient chemical acetylation. Many of the identified proteins reside outside of the mitochondria and have been previously demonstrated to be acetylated in vivo. As such, our studies demonstrate that chemical acetylation occurs more broadly throughout the eukaryotic cell than previously appreciated and suggests that this post-translational protein modification may have more diverse roles in protein function and pathway regulation.
AB - Acetylation is a post-translational modification that occurs on thousands of proteins located in many cellular organelles. This process mediates many protein functions and modulates diverse biological processes. In mammalian cells, where acetyl-CoA is the primary acetyl donor, acetylation in the mitochondria is thought to occur by chemical means due to the relatively high concentration of acetyl-CoA located in this organelle. In contrast, acetylation outside of the mitochondria is thought to be mediated predominantly by acetyltransferase enzymes. Here, we address the possibility that nonenzymatic chemical acetylation outside of the mitochondria may be more common than previously appreciated. We employed the Nucleic Acid Programmable Protein Array platform to perform an unbiased screen for human proteins that undergo chemical acetylation, which resulted in the identification of a multitude of proteins with diverse functions and cellular localization. Mass spectrometry analysis revealed that basic residues typically precede the acetylated lysine in the -7 to -3 position, and we show by mutagenesis that these basic residues contribute to chemical acetylation capacity. We propose that these basic residues lower the pKa of the substrate lysine for efficient chemical acetylation. Many of the identified proteins reside outside of the mitochondria and have been previously demonstrated to be acetylated in vivo. As such, our studies demonstrate that chemical acetylation occurs more broadly throughout the eukaryotic cell than previously appreciated and suggests that this post-translational protein modification may have more diverse roles in protein function and pathway regulation.
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U2 - 10.1021/acschembio.5b00342
DO - 10.1021/acschembio.5b00342
M3 - Article
C2 - 26083674
AN - SCOPUS:84942028125
SN - 1554-8929
VL - 10
SP - 2034
EP - 2047
JO - ACS Chemical Biology
JF - ACS Chemical Biology
IS - 9
ER -