Transient up-regulation of liver mitochondrial thymidine kinase activity in proliferating mitochondria.
Administration of the fatty acid analogue tetradecylthioacetic acid (TTA) to rodents up-regulates peroxisomal and mitochondrial lipid-metabolizing enzymes and induces a proliferation of these organelles in hepatocytes. We show here that male NMRI mice fed a diet containing 0.3% (w/w) TTA revealed a transient two-fold increase in the incorporation of [3H]thymidine into the liver mtDNA followed by a 1.6-fold increase in the content of mtDNA. In addition, a transient three-fold increase in the mitochondrial thymidine kinase (TK2) activity and a slight increase in the DNA polymerase gamma activity was observed, indicating that the TTA induced mitochondrial proliferation is linked to an up-regulation of the mitochondrial thymidine kinase activity.
Elholm
M
M
Department of Biochemistry and Molecular Biology, University of Bergen, Norway. morten.elholm@pki.uib.no
Hollås
H
H
Issalene
C
C
Barroso
J F
JF
Berge
R K
RK
Flatmark
T
T
D000818:Animals; D001483:Base Sequence; D001835:Body Weight / Q000187:drug effects; D000074002:DNA Polymerase gamma; D017931:DNA Primers; D004261:DNA Replication; D004272:DNA, Mitochondrial / Q000096:biosynthesis; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D008297:Male; D051379:Mice; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology; D009929:Organ Size / Q000187:drug effects; D013440:Sulfides / Q000494:pharmacology; D013937:Thymidine Kinase / Q000378:metabolism*; D015854:Up-Regulation
D017931:DNA Primers; D004272:DNA, Mitochondrial; D013440:Sulfides; C062078:1-(carboxymethylthio)tetradecane; D013937:Thymidine Kinase; D000074002:DNA Polymerase gamma; D004259:DNA-Directed DNA Polymerase