Effects of CoA and acyl-CoA on Ca(2+)-permeability of endoplasmic-reticulum membranes from rat liver.
Biochem J
; 306 ( Pt 3): 703-8, 1995 Mar 15.
Article
em En
| MEDLINE
| ID: mdl-7702563
ABSTRACT
We have studied the effects of CoA and palmitoyl-CoA on Ca2+ movements and GTP-dependent vesicle fusion in rat liver microsomes. (1) Inhibition of membrane fusion by CoA depends on esterification of CoA to long-chain acyl-CoA using endogenous non-esterified fatty acids. (2) Binding of long-chain acyl-CoA to microsomal membranes is inhibited by BSA, which also relieves inhibition of membrane fusion. (3) Under conditions where acyl-CoA binding is inhibited, CoA causes increased Ca2+ accumulation, apparently by decreasing the Ca2+ leak rate. (4) Conversely, palmitoyl-CoA, in the presence of BSA, causes Ca2+ efflux. (5) The decrease in Ca(2+)-permeability caused by CoA does not depend on the presence of ATP or GTP, and is irreversible in the short term. (6) Using 14C-labelled CoA we show that CoA derivatives can be formed from endogenous components of microsomal membranes in the absence of ATP. (7) The results are interpreted in terms of a Ca(2+)-permeability which is controlled by CoA and/or long-chain acyl-CoA esters.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Acil Coenzima A
/
Microssomos Hepáticos
/
Cálcio
/
Coenzima A
Limite:
Animals
Idioma:
En
Revista:
Biochem J
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Reino Unido