Lipid dynamics and protein-lipid interactions in rat colonic epithelial cell basolateral membranes.
Lipid dynamics and lipid-protein interactions were examined in basolateral membranes prepared from rat proximal and distal colonic epithelial cells. The results demonstrate that: (1) these membranes have a high lipid fluidity, as assessed by steady-state fluorescence polarization studies using seven fluorescent probes; (2) lipid compositional differences exist between these membranes but their fluidity is similar; (3) fluorescence polarization studies, using diphenylhexatriene (DPH), detect a thermotropic transition at 22-23 degrees C in each membrane; (4) several membrane protein activities, including adenylate cyclase and sodium-potassium dependent adenosine triphosphatase ((Na+ + K+)-ATPase) appear to be functionally dependent on the physical state of the proximal basolateral membrane's lipid.
D000251:Adenosine Triphosphatases / Q000032:analysis; D000818:Animals; D002458:Cell Fractionation; D002462:Cell Membrane / Q000648:ultrastructure*; D002784:Cholesterol / Q000032:analysis; D003106:Colon / Q000166:cytology / Q000648:ultrastructure*; D004848:Epithelium / Q000648:ultrastructure; D005227:Fatty Acids / Q000032:analysis; D008081:Liposomes; D008297:Male; D008563:Membrane Lipids / Q000032:analysis / Q000502:physiology*; D008565:Membrane Proteins / Q000502:physiology*; D010743:Phospholipids / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D013050:Spectrometry, Fluorescence; D014280:Triglycerides / Q000032:analysis
D005227:Fatty Acids; D008081:Liposomes; D008563:Membrane Lipids; D008565:Membrane Proteins; D010743:Phospholipids; D014280:Triglycerides; D002784:Cholesterol; D000251:Adenosine Triphosphatases