| Project/Area Number |
04454212
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Immunology
|
|---|
| Research Institution | Juntendo University School of Medicine |
|---|
Principal Investigator |
RA Chisei Dept.Immunol., Juntendo Univ.School, Med., Assoc.Pro., 医学部, 講師 (60230851)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
HIROSE Tomohiro Cent.Res.Labo., Yamanouchi Phamaceutical Co., Reserch Staff., 中央研究所, 研究員
|
|---|
| Project Period (FY) |
1992 – 1993
|
| Project Status |
Completed (Fiscal Year 1993)
|
| Budget Amount *help |
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 1993: ¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 1992: ¥3,600,000 (Direct Cost: ¥3,600,000)
|
|---|
| Keywords | FcepsilonRI / Signal transduction / Mast cell / Chimerie molecule / Syk kinase / FcepsilonRI / FсεRI / I型アレルギー / アトピー遺伝子 |
|---|
| Research Abstract |
The high affinity receptor for IgE (FcepsilonRI) is selectively expressed on mast cells, basophils, eosinophils and Langerhans cells in the skin and triggers allergic reaction. FcepsilonRI has a tetrameric structure consisting of one alpha, one beta and two gamma chains of which alpha chain binds IgE specifically and beta, gamma chains transduce signals from cell membrane into cytoplasm for cellular activation. Recombinant gene technique had enabled us to generate soluble human FcepsilonRIalpha exodomain as a secreting form (soluble alpha) from CHO cells. In order to elucidate molecular mechanisms of high affinity binding between IgE and FcepsilonRIalpha, we have to know the tertiary structure of IgE binding site on alpha chain. We succeeded in the production of soluble alpha in a large amount by baculo virus system and identified the sugar binding sites and the extent of bound-sugar at each site. For the crystallization of soluble alpha to analyze the tertiary structure of IgE binding site, we are now introducing mutations of amino acids to remove sugar in soluble alpha.
We constructed chymeric molecules composed of human FcepsilonRI alpha chain exodomain and intracellular domain of FcepsilonRI beta or gamma chain and introduced them into different kind of cell lines to analyze IgE-mediated signal transduction through a simpler single molecule. In the meantime, we cloned human Syk kinase gene and are now trying to introduce this gene into the chimeric molecule expressing transfectants to analyze the role of this kinase in FcepsilonRI-mediated signal transduction.
|
