| First Author | Gavin AL | Year | 1996 |
| Journal | J Biol Chem | Volume | 271 |
| Issue | 29 | Pages | 17091-9 |
| PubMed ID | 8663283 | Mgi Jnum | J:34159 |
| Mgi Id | MGI:81628 | Doi | 10.1074/jbc.271.29.17091 |
| Citation | Gavin AL, et al. (1996) Extracellular mutations of non-obese diabetic mouse FcgammaRI modify surface expression and ligand binding. J Biol Chem 271(29):17091-9 |
| abstractText | The non-obese diabetic mouse (NOD) expresses a unique form of the high affinity receptor for IgG (FcgammaRI), containing multiple mutations that result in substitutions and insertions of amino acids and a truncated cytoplasmic tail. As a result of these major changes, receptor affinity for IgG increases 10-fold over that of wild-type FcgammaRI from BALB/c mice, while the specificity for ligand is retained. Kinetic analysis revealed that while the association rate of IgG with FcgammaRI from NOD mice (FcgammaRI-NOD) and FcgammaRI from BALB/c mice (FcgammaRI-BALB) is similar, IgG bound much more tightly to FcgammaRI-NOD as revealed by a profoundly diminished dissociation rate. Transfection studies demonstrated that FcgammaRI-NOD was expressed at one-tenth of the level of FcgammaRI-BALB. Although mouse FcgammaRI was previously not known to associate with the FcepsilonRI gamma-subunit, transfection of COS-7 cells demonstrates that like human FcgammaRI, mouse FcgammaRI is also able to associate with this signaling subunit. Furthermore, expression levels of FcgammaRI-NOD were not restored by the presence of the FcepsilonRI gamma-subunit. The difference in the levels of expression was mapped to mutations in the extracellular region of FcgammaRI-NOD as replacement of the extracellular domains with those of human FcgammaRI or FcgammaRI-BALB restored expression to that of human FcgammaRI or FcgammaRI-BALB. |
