acyl aliquoted angiogenesis apoptosis artifactual ATP CHOL cholchicine depolarizes der diacylglycerol dPOPC Histone isoforms lamellar lyotropic microdomain microdomains microtubules mL mM mol mtorr ng NMR phosphatidyl phospholipids phosphorylated physicochemical PKC POPC recombinant serine sphingomyelin steric synergize synergizes thermotropic transmembrane tubulin tumorigenesis unsaturation