Sw. Kim et al., Differential effects of annexins I, II, III, and V on cytosolic phospholipase A2 activity: specific interaction model, FEBS LETTER, 489(2-3), 2001, pp. 243-248
Annexins (ANXs) are a family of proteins with calcium-dependent phospholipi
d binding properties, Although inhibition of phospholipase A2 (PLA2) by ANX
-I has been reported, the mechanism is still controversial. Previously we p
roposed a 'specific interaction' model for the mechanism of cytosolic PLA2
(cPLA2) inhibition by ANX-I [Kim et al., FEES Lett. 343 (1993) 251-255]. He
re we have studied the cPLA2 inhibition mechanism using ANX-I, N-terminally
deleted ANX-I (Delta ANX-I), ANX-II, ANX-II(2)P11(2), ANX-III, and ANX-V.
Under the conditions for the specific interaction model, ANX-I, Delta ANX-I
, and ANX-II(2)P11(2) inhibited cPLA2, whereas inhibition by ANX-II and ANX
-III was negligible, Inhibition by ANX-V was much smaller than that by ANX-
I. The protein-protein interactions between cPLA2 and ANX-I, Delta ANX-I, a
nd ANXII(2)P11(2) were verified by immunoprecipitation. We can therefore co
nclude that inhibition of cPLA2 by specific interaction is not a general fu
nction of all ANXs, and is rather a specific function of ANX-I. The results
are consistent with the specific interaction model. (C) 2001 Federation of
European Biochemical Societies. Published by Elsevier Science B.V. All rig
hts reserved.