Submitted on February 29, 2008
Accepted on August 11, 2008
A Lipid-Protein Hybrid Model for Tight Junction
David B. N. Lee1*, Nora Jamgotchian2, Suni G Allen3, Michael B Abeles2, and Harry J. Ward4
1 Medicine, VA Greater Los Angeles Healthcare System, Encino, California, United States
2 Research Service, Veterans Administration, North Hills, California, United States
3 Research Servic, Veterans Administration, North Hills, California, United States
4 Medicine, Rancho Los Amigos Medical Center, Los Angeles, California, United States
* To whom correspondence should be addressed. E-mail: dbnlee{at}ucla.edu.
Epithelial tight junction (TJ) was first described ultrastructurally, as a fusion of the outer lipid leaflets of the adjoining cell membrane bilayers (hemifusion). The discovery of increasing number of integral TJ and TJ-associated proteins has eclipsed the original lipid-based model with the wide-acceptance of a protein-centric model for TJ. In this review we stress the importance of lipids in TJ structure and function. A lipid-protein hybrid model accommodates a large body of information supporting the lipidic characteristics of the TJ, harmonizes with the accumulating evidence supporting TJ as an assembly of lipid rafts and focuses on an important, but relatively unexplored, field of lipid-protein interactions in the morphology, physiology and pathophysiology of the TJ.
