Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
International Immunology
Year: 2009  |  Volume: 21  |  Issue: 8  |  Page No.: 925 - 934

Mutational analysis of Cys88 of Toll-like receptor 4 highlights the critical role of MD-2 in cell surface receptor expression

C Nishitani, M Takahashi, H Mitsuzawa, T Shimizu, S Ariki, N Matsushima and Y. Kuroki    

Abstract:

The role of MD-2 in cell surface expression of Toll-like receptor (TLR) 4 has been controversial. The purposes of this study were to characterize the N-glycan of TLR4 and to investigate the roles of MD-2 in N-linked glycosylation and cell surface expression of TLR4. Lectin blot and cell surface biotinylation revealed that TLR4 exhibited the 110 kDa protein with high mannose type N-glycans and the 130 kDa protein with complex type N-glycans and that only the 130 kDa TLR4 with complex type N-glycans was expressed on the cell surface. The cells transfected with a mutant TLR4C88A alone expressed only the 110 kDa TLR4 with a high mannose type N-glycan, which did not appear on the cell surface. However, TLR4C88A acquired complex type N-glycans and was expressed on the cell surface when MD-2 was co-transfected. The amount of the 130 kDa TLR4C88A with complex type N-glycans expressed on the cell surface depended on that of MD-2 transfected. -Mannosidase II inhibitor blocked the processing N-glycans to complex type, but TLR4 with high mannose type appeared on the cell surface, suggesting that TLR4 is destined to locate on the cell surface before processing N-glycans from a high mannose type to a complex type. From these results, we conclude that MD-2 is critical for cell surface expression of TLR4C88A. This study provides evidence that MD-2 possesses potential ability to play an essential role in cell surface expression of TLR4.

View Fulltext    |   Related Articles   |   Back
   
 
 
 
  Related Articles

No Article Found
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility