Skip to main content
. 2009 Apr 17;284(16):10694–10705. doi: 10.1074/jbc.M807136200

FIGURE 4.

FIGURE 4.

Phosphorylation of the serine-rich region of IRBIT is necessary, but not sufficient, for interaction with Fip1. A, schematic representation of the structure of IRBIT, showing the N-terminal region (NTR), the C-terminal region (CTR), the serine-rich region (SER), and the HA-tagged deletion mutants. B, COS-7 cells were transfected with HA-tagged deletion mutants of IRBIT and processed for pulldown assay with GST or R domain of Fip1. Cell lysates (Input) and pulled down samples were analyzed by Western blotting with anti-HA antibody. C, COS-7 cells were transfected with HA-tagged serine/threonine-substituted mutants of IRBIT and subjected to pulldown assay with GST or R domain of Fip1 and to Western blotting with anti-HA antibody. D, pulldown experiment with recombinant IRBIT purified from E. coli and Sf9 cells. Sf9-expressed IRBIT was incubated with or without alkaline phosphatase (AP) prior to pulldown assay with GST or R domain of Fip1. The samples were analyzed by Western blotting with anti-IRBIT antibody.