Involvement of cyclophilin D in mitochondrial permeability transition induction in intact cells.
The mitochondrial permeability transition (MPT) is involved in both Ca(2+) signaling and cell death. The present study aimed to clarify the involvement of cyclophilin D, a peptidyl prolyl cis-trans isomerase (PPIase), in MPT induction in intact cells. To achieve this, we used C6 cells overexpressing wild-type or PPIase-deficient cyclophilin D, and measured the inner mitochondrial membrane permeability to calcein, a 623-Da hydrophilic fluorescent molecule, to evaluate MPT induction. In vector control cells, the percentage of MPT induction by ionomycin increased as the Ca(2+) concentration in the extracellular medium increased. This result indicates that the present method is valid for numerical evaluation of MPT induction. In C6 cells expressing the PPIase-deficient mutant, the percentage of MPT induction was significantly decreased compared with wild-type CypD-overexpressing cells or vector control cells. These results suggest that cyclophilin D is involved in MPT induction by Ca(2+) in intact cells.
Tazawa
Hidejiro
H
Division of Biotechnology and Life Science, Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Nakacho 2-24-16, Koganei, Tokyo, Japan.
Fujita
Chisako
C
Machida
Kiyotaka
K
Osada
Hiroyuki
H
Ohta
Yoshihiro
Y
D000818:Animals; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D000081406:Peptidyl-Prolyl Isomerase F; D021983:Cyclophilins / Q000235:genetics / Q000502:physiology*; D005452:Fluoresceins / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D015759:Ionomycin / Q000494:pharmacology; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D051336:Mitochondrial Membranes / Q000187:drug effects / Q000378:metabolism*; D009154:Mutation; D019696:Peptidylprolyl Isomerase / Q000096:biosynthesis / Q000235:genetics; D010539:Permeability; D051381:Rats
D000081406:Peptidyl-Prolyl Isomerase F; D005452:Fluoresceins; D005456:Fluorescent Dyes; D015759:Ionomycin; D021983:Cyclophilins; D019696:Peptidylprolyl Isomerase; D002118:Calcium; C007740:fluorexon