Mitochondrial sAC-cAMP-PKA Axis Modulates the ΔΨm-Dependent Control Coefficients of the Respiratory Chain Complexes : Evidence of Respirasome Plasticity

The current view of the mitochondrial respiratory chain complexes I, III and IV foresees the occurrence of their assembly in supercomplexes, providing additional functional properties when compared with randomly colliding isolated complexes. According to the plasticity model, the two structural states of the respiratory chain may interconvert, influenced by the intracellular prevailing conditions. In previous studies, we suggested the mitochondrial membrane potential as a factor for controlling their dynamic balance. Here, we investigated if and how the cAMP/PKA-mediated signalling influences the aggregation state of the respiratory complexes. An analysis of the inhibitory titration profiles of the endogenous oxygen consumption rates in intact HepG2 cells with specific inhibitors of the respiratory complexes was performed to quantify, in the framework of the metabolic flux theory, the corresponding control coefficients. The attained results, pharmacologically inhibiting either PKA or sAC, indicated that the reversible phosphorylation of the respiratory chain complexes/supercomplexes influenced their assembly state in response to the membrane potential. This conclusion was supported by the scrutiny of the available structure of the CI/CIII2/CIV respirasome, enabling us to map several PKA-targeted serine residues exposed to the matrix side of the complexes I, III and IV at the contact interfaces of the three complexes.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:24

Enthalten in:

International journal of molecular sciences - 24(2023), 20 vom: 13. Okt.

Sprache:

Englisch

Beteiligte Personen:

Scrima, Rosella [VerfasserIn]
Cela, Olga [VerfasserIn]
Rosiello, Michela [VerfasserIn]
Nabi, Ari Qadir [VerfasserIn]
Piccoli, Claudia [VerfasserIn]
Capitanio, Giuseppe [VerfasserIn]
Tucci, Francesco Antonio [VerfasserIn]
Leone, Aldo [VerfasserIn]
Quarato, Giovanni [VerfasserIn]
Capitanio, Nazzareno [VerfasserIn]

Links:

Volltext

Themen:

CAMP/PKA signaling pathway
EC 7.1.1.2
Electron Transport Complex I
Journal Article
Metabolic flux theory
Mitochondrial membrane potential
Mitochondrial respiratory chain complexes
Soluble adenylate cyclase
Supercomplexes

Anmerkungen:

Date Completed 30.10.2023

Date Revised 30.10.2023

published: Electronic

Citation Status MEDLINE

doi:

10.3390/ijms242015144

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM363868402