Lipid raft composition modulates sphingomyelinase activity and ceramide-induced membrane physical alterations.

ABSTRACT: Lipid rafts and ceramide (Cer)-platforms are membrane domains that play an important role in several biological processes. Cer-platforms are commonly formed in the plasma membrane by the action of sphingomyelinase (SMase) upon hydrolysis of sphingomyelin (SM) within lipid rafts. The interplay among SMase activity, initial membrane properties (i.e., phase behavior and lipid lateral organization) and lipid composition, and the amount of product (Cer) generated, and how it modulates membrane properties were studied using fluorescence methodologies in model membranes. The activity of SMase was evaluated by following the hydrolysis of radioactive SM. It was observed that 1), the enzyme activity and extent of hydrolysis are strongly dependent on membrane physical properties but not on substrate

SUBMITTER: Silva LC 

PROVIDER: S-EPMC2718262 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature