TY - JOUR
T1 - Chemical acetylation of mitochondrial transcription factor A occurs on specific lysine residues and affects its ability to change global DNA topology
AU - Fang, Yuan
AU - Akimoto, Masaru
AU - Mayanagi, Kouta
AU - Hatano, Atsushi
AU - Matsumoto, Masaki
AU - Matsuda, Shigeru
AU - Yasukawa, Takehiro
AU - Kang, Dongchon
N1 - Funding Information:
We thank Dr. Daiki Setoyama for valuable discussion. This work was supported in part by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science [ JSPS KAKENHI , Japan grant numbers: 18K06089 to K.M, 17K07504 to T.Y., 17H01550 to K.D.]
Publisher Copyright:
© 2020 Elsevier B.V. and Mitochondria Research Society
PY - 2020/7
Y1 - 2020/7
N2 - Chemical acetylation is postulated to occur in mitochondria. Mitochondrial transcription factor A (TFAM or mtTFA), a mitochondrial transcription initiation factor as well as the major mitochondrial nucleoid protein coating the entire mitochondrial genome, is proposed to be acetylated in animals and cultured cells. This study investigated the properties of human TFAM, in conjunction with the mechanism and effects of TFAM acetylation in vitro. Using highly purified recombinant human TFAM and 3 kb circular DNA as a downsized mtDNA model, we studied how the global TFAM–DNA interaction is affected/regulated by the quantitative TFAM–DNA relationship and TFAM acetylation. Results showed that the TFAM–DNA ratio strictly affects the TFAM property to unwind circular DNA in the presence of topoisomerase I. Mass spectrometry analysis showed that in vitro chemical acetylation of TFAM with acetyl-coenzyme A occurs preferentially on specific lysine residues, including those reported to be acetylated in exogenously expressed TFAM in cultured human cells, indicating that chemical acetylation plays a crucial role in TFAM acetylation in mitochondria. Intriguingly, the modification significantly decreased TFAM's DNA-unwinding ability, while its DNA-binding ability was largely unaffected. Altogether, we propose TFAM is chemically acetylated in vivo, which could change mitochondrial DNA topology, leading to copy number and gene expression modulation.
AB - Chemical acetylation is postulated to occur in mitochondria. Mitochondrial transcription factor A (TFAM or mtTFA), a mitochondrial transcription initiation factor as well as the major mitochondrial nucleoid protein coating the entire mitochondrial genome, is proposed to be acetylated in animals and cultured cells. This study investigated the properties of human TFAM, in conjunction with the mechanism and effects of TFAM acetylation in vitro. Using highly purified recombinant human TFAM and 3 kb circular DNA as a downsized mtDNA model, we studied how the global TFAM–DNA interaction is affected/regulated by the quantitative TFAM–DNA relationship and TFAM acetylation. Results showed that the TFAM–DNA ratio strictly affects the TFAM property to unwind circular DNA in the presence of topoisomerase I. Mass spectrometry analysis showed that in vitro chemical acetylation of TFAM with acetyl-coenzyme A occurs preferentially on specific lysine residues, including those reported to be acetylated in exogenously expressed TFAM in cultured human cells, indicating that chemical acetylation plays a crucial role in TFAM acetylation in mitochondria. Intriguingly, the modification significantly decreased TFAM's DNA-unwinding ability, while its DNA-binding ability was largely unaffected. Altogether, we propose TFAM is chemically acetylated in vivo, which could change mitochondrial DNA topology, leading to copy number and gene expression modulation.
KW - Acetylation
KW - Mitochondria
KW - TFAM
KW - Topology
KW - mtDNA
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U2 - 10.1016/j.mito.2020.05.003
DO - 10.1016/j.mito.2020.05.003
M3 - Article
C2 - 32439622
AN - SCOPUS:85085054646
VL - 53
SP - 99
EP - 108
JO - Mitochondrion
JF - Mitochondrion
SN - 1567-7249
ER -