Homologous and heterologous inhibitory effects of ATPase inhibitor proteins on F-ATPases.

TitleHomologous and heterologous inhibitory effects of ATPase inhibitor proteins on F-ATPases.
Publication TypeJournal Article
Year of Publication2002
AuthorsCabezon, E, P Butler, JG, Runswick, MJ, Carbajo, RJ, Walker, JE
JournalJ Biol Chem
Date Published2002 Nov 01
KeywordsAmino Acid Sequence, Animals, Cattle, Fungal Proteins, Hydrogen-Ion Concentration, Molecular Sequence Data, Proton-Translocating ATPases, Saccharomyces cerevisiae

In Saccharomyces cerevisiae, at least three proteins (IF(1), STF(1), and STF(2)) appear to be involved in the regulation of ATP synthase. Both IF(1) and STF(1) inhibit F(1), whereas the proposed function for STF(2) is to facilitate the binding of IF(1) and STF(1) to F(1). The oligomerization properties of yeast IF(1) and STF(1) have been investigated by sedimentation equilibrium analytical ultracentrifugation and by covalent cross-linking. Both techniques confirm that IF(1) and STF(1) oligomerize in opposite directions in relation to pH, suggesting that both proteins might regulate yeast F(1)F(0)-ATPase under different conditions. Their effects on bovine F-ATPases are also described. Whereas bovine IF(1) inhibits yeast F(1)-ATPase even better than yeast IF(1) or STF(1), the capability of yeast IF(1) to inhibit the bovine enzyme is very low and decreases with time. Such an effect is also observed in the study of the homologous inhibition of yeast F(1)-ATPase. Yeast inhibitors are not as effective as their bovine counterpart, and the complex seems to dissociate gradually.

Alternate JournalJ. Biol. Chem.
Citation Key10.1074/jbc.M207169200
PubMed ID12186878