CD24 induces localization of beta1 integrin to lipid raft domains

• Published in: Biochemical and biophysical research communications Vol. 365; no. 1; pp. 35 - 41
• Main Authors: Runz, Steffen, Mierke, Claudia T, Joumaa, Safwan, Behrens, Jürgen, Fabry, Ben, Altevogt, Peter
• Format: Journal Article
• Language: English
• Published: United States 04-01-2008
• Subjects: Breast Neoplasms - metabolism; CD24 Antigen - metabolism; Cell Line, Tumor; Female; Humans; Integrin beta1 - analysis; Integrin beta1 - immunology; Lung Neoplasms - metabolism; Membrane Microdomains - metabolism; Protein Subunits - analysis; Transfection
• ISSN: 1090-2104

The expression of the glycosyl phosphatidylinositol (GPI)-anchored protein CD24 correlates with poor prognosis in a variety of carcinomas. However, little is known about the cellular mechanisms of the CD24-mediated effects. In this study, we present evidence that CD24 affects the lateral localization of beta1 integrin. Using stably CD24-transfected A125 and MDA-MB-435S carcinoma cells we show that CD24 augments beta1-dependent cell motility and stimulates transmigration and invasion across a monolayer of endothelial cells. Furthermore, as demonstrated by sucrose density gradient centrifugation and Western Blot analysis, CD24 recruits beta1 integrin into lipid raft domains. We suggest that CD24 acts as a gate-keeper for lipid rafts, thereby regulating the activity of integrins and other proteins.