Phospholipid-dependence of rat liver plasma membrane protein kinase activities--a new approach.
The influence of the phospholipid composition and fluidity on protein kinase A and protein kinase C activities in rat liver plasma membranes was studied. We observed that enrichment of membranes with phosphatidylglycerol, phosphatidylserine, phosphatidylethanolamine and dioleoylphosphatidylcholine caused activation of both protein kinases. Phosphatidylglycerol was found to be most effective activator. The enrichment of plasma membranes with dipalmitoylphosphatidylcholine and sphingomyelin led to decrease in protein kinase A and C activities. The stimulatory effect of phosphatidylglycerol was confirmed in plasma membranes pretreated with exogenous phospholipases A2, C and D, and subsequently enriched with phosphatidylglycerol. We suggest that besides the specific presence of definite phospholipids protein kinases A and C require a more fluid membrane lipid bilayer to display an optimal activity.
Gavrilova
N J
NJ
Central Laboratory of Biophysics, Bulgarian Academy of Sciences, Sofia.
Markovska
T T
TT
Momchilova-Pankova
A B
AB
Setchenska
M S
MS
Koumanov
K S
KS
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology*; D005456:Fluorescent Dyes; D066298:In Vitro Techniques; D008099:Liver / Q000201:enzymology* / Q000648:ultrastructure; D008297:Male; D010743:Phospholipids / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D005456:Fluorescent Dyes; D010743:Phospholipids; D011494:Protein Kinases; D011493:Protein Kinase C