Your browser version may not work well with NCBI's Web applications. More information here...
1: J Cell Biol. 2008 Aug 25;182(4):765-76. Epub 2008 Aug 18.
Related Articles, Links
Click here to read Click here to read
Single-molecule analysis of CD9 dynamics and partitioning reveals multiple modes of interaction in the tetraspanin web.

Espenel C, Margeat E, Dosset P, Arduise C, Le Grimellec C, Royer CA, Boucheix C, Rubinstein E, Milhiet PE.

Institut National de la Santé et de la Recherche Medicale, Unité 554, Montpellier, France.

Tetraspanins regulate cell migration, sperm-egg fusion, and viral infection. Through interactions with one another and other cell surface proteins, tetraspanins form a network of molecular interactions called the tetraspanin web. In this study, we use single-molecule fluorescence microscopy to dissect dynamics and partitioning of the tetraspanin CD9. We show that lateral mobility of CD9 in the plasma membrane is regulated by at least two modes of interaction that each exhibit specific dynamics. The majority of CD9 molecules display Brownian behavior but can be transiently confined to an interaction platform that is in permanent exchange with the rest of the membrane. These platforms, which are enriched in CD9 and its binding partners, are constant in shape and localization. Two CD9 molecules undergoing Brownian trajectories can also codiffuse, revealing extra platform interactions. CD9 mobility and partitioning are both dependent on its palmitoylation and plasma membrane cholesterol. Our data show the high dynamic of interactions in the tetraspanin web and further indicate that the tetraspanin web is distinct from raft microdomains.

Publication Types:
PMID: 18710926 [PubMed - indexed for MEDLINE]

PMCID: PMC2518714 [Available on 02/25/09]