title: Laser controlled singlet oxygen generation in mitochondria to promote mitochondrial DNA replication in vitro.
abstract: Reports have shown that a certain level of reactive oxygen species (ROS) can promote mitochondrial DNA (mtDNA) replication. However, it is unclear whether it is the mitochondrial ROS that stimulate mtDNA replication and this requires further investigation. Here we employed a photodynamic system to achieve controlled mitochondrial singlet oxygen ((1)O2) generation. HeLa cells incubated with 5-aminolevulinic acid (ALA) were exposed to laser irradiation to induce (1)O2 generation within mitochondria. Increased mtDNA copy number was detected after low doses of 630 nm laser light in ALA-treated cells. The stimulated mtDNA replication was directly linked to mitochondrial (1)O2 generation, as verified using specific ROS scavengers. The stimulated mtDNA replication was regulated by mitochondrial transcription factor A (TFAM) and mtDNA polymerase γ. MtDNA control region modifications were induced by (1)O2 generation in mitochondria. A marked increase in 8-Oxoguanine (8-oxoG) level was detected in ALA-treated cells after irradiation. HeLa cell growth stimulation and G1-S cell cycle transition were also observed after laser irradiation in ALA-treated cells. These cellular responses could be due to a second wave of ROS generation detected in mitochondria. In summary, we describe a controllable method of inducing mtDNA replication in vitro.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.|Graduate School of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Yupei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Si
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Gan
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Cuixia
authors.initials: C
authors.lastname: Di
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.|Key laboratory of Heavy Ion Radiation Biology and Medicine Institute of Nuclear Physics, Chinese Academy of Sciences.|Key laboratory of Heavy-ion Radiation Medicine of Gansu Province, Lanzhou 730000, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
mesh_terms: D049109:Cell Proliferation; D000074002:DNA Polymerase gamma; D004261:DNA Replication / Q000528:radiation effects*; D004272:DNA, Mitochondrial / Q000528:radiation effects*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D018628:Gene Dosage; D006147:Guanine / Q000031:analogs & derivatives / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D007834:Lasers; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects*; D024101:Mitochondrial Proteins / Q000378:metabolism; D018384:Oxidative Stress / Q000235:genetics; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology; D011524:Protoporphyrins / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D004272:DNA, Mitochondrial; D004268:DNA-Binding Proteins; D024101:Mitochondrial Proteins; D017319:Photosensitizing Agents; D011524:Protoporphyrins; D017382:Reactive Oxygen Species; C499631:TFAM protein, human; D014157:Transcription Factors; D026082:Singlet Oxygen; C024829:8-hydroxyguanine; D006147:Guanine; C028025:protoporphyrin IX; D000074002:DNA Polymerase gamma; D004259:DNA-Directed DNA Polymerase