Pleckstrin homology domains interact with filamentous actin.


A fraction of Bruton's tyrosine kinase (Btk) co-localizes with actin fibers upon stimulation of mast cells via the high affinity IgE receptor (FcepsilonRI). In this study, a molecular basis of the Btk co-localization with actin fibers is presented. Btk and other Tec family tyrosine kinases have a pleckstrin homology (PH) domain at their N termini. The PH domain is a short peptide module frequently found in signal-transducing proteins and cytoskeletal proteins. Filamentous actin (F-actin) is shown to be a novel ligand for a subset of PH domains, including that of Btk. The actin-binding site was mapped to a 10-residue region of the N-terminal region of Btk. Basic residues in this short stretch are demonstrated to be involved in actin binding. Isolated PH domains induced actin filament bundle formation. Consistent with these observations, Btk binds F-actin in vitro and in vivo. Wild-type Btk protein is in part translocated to the cytoskeleton upon FcepsilonRI cross-linking, whereas Btk containing a mutated PH domain is not. Phosphatidylinositol 3,4, 5-trisphosphate-mediated membrane translocation of Btk was enhanced in cytochalasin D-pretreated, FcepsilonRI-stimulated mast cells. These data indicate that PH domain-mediated F-actin binding plays a role in Btk co-localization with actin filaments.


Citations per Year

118 Citations

Semantic Scholar estimates that this publication has 118 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Yao1999PleckstrinHD, title={Pleckstrin homology domains interact with filamentous actin.}, author={Li Hua Yao and Paul A. Janmey and Luciano G Frigeri and W K Han and Jiro Fujita and Yasuo Kawakami and John R. Apgar and Toshiyuki Kawakami}, journal={The Journal of biological chemistry}, year={1999}, volume={274 28}, pages={19752-61} }