Regulation of ATP hydrolase activity of the F0‐F1 complex of rat‐liver mitochondria during early hepatic regeneration

FEBS Letters

Buckle, Malcolm¹ 

[1] Institute of Medical Biochemistry and Chemistry, University of Bari, Bari, Italy

关键词: F1F0-H+-ATP synthase;    Liver regeneration;    Mitochondria;    F0;    membrane integral sector of mitochondrial H+-ATPase;    F1;    catalytic part of mitochondrial H+-ATPase;    ESMP;    submitochondrial particles prepared in the presence of EDTA;    [β;    γ-imido]ATP;    adenosine 5'-[β;    γ-imido]triphosphate. Enzymes: ATPase (EC 3.6.1.3);    pyruvate kinase (EC 2.7.1.40);    lactate dehydrogenase (EC 1.1.1.27);   

DOI  :  10.1016/0014-5793(86)81110-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Submitochondrial particles prepared from rat liver in the early phase of hepatic regeneration possess a reduced F₁ content with respect to F₀ in intact F₀F₁-H⁺-ATPase complexes. Analysis of ATP hydrolysis showed a significant difference in both ESMP and isolated F₁ with regard to the higher affinity K _m values (K _m,1) obtained from Eadie-Hofstee plots. Both ESMP and F₁ from regenerating rat liver showed much lower apparent K _m,1 values (0.04 and 0.03 mM, respectively) than the corresponding controls (0.08 mM for both ESMP and F₁). Data presented here show that the residual F₁ moieties have an altered kinetic pattern with regard to the competitive inhibitor adenosine 5'-[β,γ-imido]triphospate (K ₁ ESMP from regenerating rat liver = 0.67 μM, K ₁ ESMP from control rat liver = 2.03 μM). This difference in affinity for [β,γ-imido]-ATP is also seen in isolated F₁(K₁ regenerating rat liver = 0.04 μM, K ₁ control rat liver = 0.22 μM). These data indicate that during the disruptive retrodifferential phase of hepatic regeneration, changes at the level of surviving F₁ sectors of the F₀-F₁ ATPase may play a physiological role in preventing ATP hydrolysis in vivo in the brief period of low ΔμH⁺, induced by the presence of non-F₁-associated F₀ proton-conducting pathways.

【 授权许可】

Unknown