Subcellular reorganization of mitochondria producing heavy DNA in aging wheat coleoptiles

FEBS Letters

Vanyushin, B.F¹  Shorning, B.Yu¹  Bakeeva, L.E¹  Kirnos, M.D¹  Kazimirchyuk, S.B¹  Aleksandrushkina, N.I¹  Yaguzhinsky, L.S¹  Zamyatnina, V.A¹ 

[1] Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119899, Russia

关键词: Aging;    Apoptosis;    DNA synthesis;    Heavy DNA;    Mitochondria;    Mitochondrial DNA;    Plant;    Wheat;    BSA;    bovine serum albumin;    DTE;    dithioerythritol;    EGTA;    ethylene glycol-bis(β-aminoethyl ether) N;    N;    N′;    N′-tetraacetic acid;    HEPES;    (N-[2-hydroxyethyl]piperazine-N′-2-ethanesulfonic acid]);    H-mtDNA;    heavy mitochondrial DNA;    nDNA;    nuclear DNA;   

DOI  :  10.1016/S0014-5793(99)01025-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Unusual closed membrane vesicles containing one or more mitochondria were isolated from homogenates of aging wheat coleoptiles. Very similar (or the same) bodies were shown to exist in situ in vacuoles of undividing cells in the apical part of intact senescent coleoptiles. Vesicles isolated from coleoptile homogenate free of nuclei by 10 min centrifugation at 1700×g and traditional mitochondria (sedimented at between 4300×g and 17 400×g) are similar in respiration rate, composition and content of cytochromes and sensitivity to respiration inhibitors. However, vesicles contain about 2-fold more Ca²⁺ ions than free mitochondria do. The specific feature of vesicles containing mitochondria in aging coleoptiles is an intensive synthesis of heavy (ρ=1.718 g/cm³) mitochondrial DNA (H-mtDNA). Thus, aging in plants is accompanied by an increased selective H-mtDNA production and change in subcellular organization of mitochondria.

【 授权许可】

Unknown