Membrane raft redox signalosomes in endothelial cells

Abstract

Membrane rafts (MRs) are specialized microdomains in the cell membrane with an altered lipid composition. Upon various stimulations, MRs can be clustered to aggregate or recruit NADPH oxidase sub-units and related proteins to form MR redox signalosomes in the membrane of cells like vascular endothelial cells (ECs). Multiple protein complexes, like MR redox signalosomes, are now considered to play a crucial role in the regulation of cell function and in the development of different cell dysfunctions. To form such redox signalosomes, ceramide will be generated from the hydrolysis of sphingomyelin by lysosomal acid sphingomyelinase that has been translocated via lysosome fusion to the MR area. In this brief review, current information is provided to help understand the occurrence and function of MR redox signalosomes. This may increase enthusiasm of the scientific community for further studies on the molecular mechanisms and the functional significance of forming such MR redox signalosomes.

Keywords::

• Lipid microdomains
• ceramide
• reactive oxygen species
• lysosome
• signal transduction
• endothelium

Declaration of interest: Many studies from our laboratory cited in this review were supported by grants from the National Institute of Health (HL-57244, HL-75316, and DK54927). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 20 May 2010.