Molecular mechanism on forcible ejection of ATPase inhibitory factor 1 from mitochondrial ATP synthase.
Nat Commun
; 14(1): 1682, 2023 03 31.
Article
en En
| MEDLINE
| ID: mdl-37002198
ABSTRACT
IF1 is a natural inhibitor protein for mitochondrial FoF1 ATP synthase that blocks catalysis and rotation of the F1 by deeply inserting its N-terminal helices into F1. A unique feature of IF1 is condition-dependent inhibition; although IF1 inhibits ATP hydrolysis by F1, IF1 inhibition is relieved under ATP synthesis conditions. To elucidate this condition-dependent inhibition mechanism, we have performed single-molecule manipulation experiments on IF1-inhibited bovine mitochondrial F1 (bMF1). The results show that IF1-inhibited F1 is efficiently activated only when F1 is rotated in the clockwise (ATP synthesis) direction, but not in the counterclockwise direction. The observed rotational-direction-dependent activation explains the condition-dependent mechanism of IF1 inhibition. Investigation of mutant IF1 with N-terminal truncations shows that the interaction with the γ subunit at the N-terminal regions is crucial for rotational-direction-dependent ejection, and the middle long helix is responsible for the inhibition of F1.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ATPasas de Translocación de Protón
/
ATPasas de Translocación de Protón Mitocondriales
Límite:
Animals
Idioma:
En
Revista:
Nat Commun
Asunto de la revista:
BIOLOGIA
/
CIENCIA
Año:
2023
Tipo del documento:
Article
País de afiliación:
Japón