Filamin A stabilizes Fc gamma RI surface expression and prevents its lysosomal routing.

Article Details


Beekman JM, van der Poel CE, van der Linden JA, van den Berg DL, van den Berghe PV, van de Winkel JG, Leusen JH

Filamin A stabilizes Fc gamma RI surface expression and prevents its lysosomal routing.

J Immunol. 2008 Mar 15;180(6):3938-45.

PubMed ID
18322202 [ View in PubMed

Filamin A, or actin-binding protein 280, is a ubiquitously expressed cytosolic protein that interacts with intracellular domains of multiple receptors to control their subcellular distribution, and signaling capacity. In this study, we document interaction between FcgammaRI, a high-affinity IgG receptor, and filamin A by yeast two-hybrid techniques and coimmunoprecipitation. Both proteins colocalized at the plasma membrane in monocytes, but dissociated upon FcgammaRI triggering. The filamin-deficient cell line M2 and a filamin-reconstituted M2 subclone (A7), were used to further study FcgammaRI-filamin interactions. FcgammaRI transfection in A7 cells with filamin resulted in high plasma membrane expression levels. In filamin-deficient M2 cells and in filamin RNA-interference studies, FcgammaRI surface expression was consistently reduced. FcgammaRI localized to LAMP-1-positive vesicles in the absence of filamin as shown by confocal microscopy indicative for lysosomal localization. Mouse IgG2a capture experiments suggested a transient membrane expression of FcgammaRI before being transported to the lysosomes. These data support a pivotal role for filamin in FcgammaRI surface expression via retention of FcgammaRI from a default lysosomal pathway.

DrugBank Data that Cites this Article

NameUniProt ID
High affinity immunoglobulin gamma Fc receptor IP12314Details