Dupont C H, Rigoulet M, Beauvoit B, Guérin B
Institut de Biochimie Cellulaire et Neurochimie, CNRS, Bordeaux, France.
Curr Genet. 1990 Jun;17(6):507-13. doi: 10.1007/BF00313079.
This paper reports studies of bioenergetic modifications in a TTR1 single-nuclear mutant, isolated as resistant to triethyltin, an inhibitor of mitochondrial ATPase, and effective in cAMP-dependent protein phosphorylation. This mutant appears to have lost the wild-type cell ability to respond to a decrease of oxygen concentration in the growth medium by a decrease of cytochrome concentration in the cell. ATP synthesis rate in mutant cells in both the prestationary and stationary phase of growth appeared increased in comparison to wild-type cells, as too was respiration rate. A comparative study of mitochondria extracted from wild-type and from TTR1 mutant cells showed an increase in respiration rate, an increase in ATP synthesis rate, and an increase in TPP+ uptake in mutant mitochondria. The specific ATPase activity, as well as its sensitivity to TET, appears to be similar for mitochondria extracted from both strains. It was proposed that the modification of mitochondrial biogenesis in the TTR1 mutant may be due to a response of the cell to an increase in ATP hydrolysis caused by the mutation. It is also possible that the modification in cAMP-dependent protein kinase regulation which appeared to occur in this mutant affects protein(s) involved in mitochondrial biogenesis.
本文报道了对TTR1单核突变体生物能量学改变的研究。该突变体是从对线粒体ATP酶抑制剂三乙基锡具有抗性的菌株中分离出来的，并且在cAMP依赖性蛋白磷酸化方面具有活性。该突变体似乎丧失了野生型细胞通过降低细胞色素浓度来响应生长培养基中氧浓度降低的能力。与野生型细胞相比，突变体细胞在生长的静止前期和静止期的ATP合成速率均有所增加，呼吸速率也是如此。对从野生型和TTR1突变体细胞中提取的线粒体进行的比较研究表明，突变体线粒体的呼吸速率增加、ATP合成速率增加以及TPP +摄取增加。从两种菌株中提取的线粒体的特异性ATP酶活性及其对三乙基锡的敏感性似乎相似。有人提出，TTRl突变体中线粒体生物发生的改变可能是由于细胞对突变引起的ATP水解增加的反应。也有可能在该突变体中出现的cAMP依赖性蛋白激酶调节的改变影响了参与线粒体生物发生的蛋白质。
