Related Experiment Video
Updated: Aug 7, 2026

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
Cytoskeletal protein PSTPIP1 directs the PEST-type protein tyrosine phosphatase to the c-Abl kinase to mediate Abl
1Department of Biochemistry and Molecular Biophysics, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
Abstract:
A search for c-Abl interacting proteins resulted in the recovery of PSTPIP1, originally identified as a binding protein of the PEST-type protein tyrosine phosphatases (PTP). PSTPIP1 was phosphorylated by c-Abl, and growth factor-induced PSTPIP1 phosphorylation was diminished in Abl null fibroblasts. PSTPIP1 was able to bridge c-Abl to the PEST-type PTPs. Several experiments suggest that the PEST-type PTPs negatively regulate c-Abl activity: c-Abl was hyperphosphorylated in PTP-PEST-deficient cells; disruption of the c-Abl-PSTPIP1-PEST-type PTP ternary complex by overexpression of PSTPIP1 mutants increased c-Abl phosphotyrosine content; and PDGF-induced c-Abl kinase activation was prolonged in PTP-PEST-deficient cells. Dephosphorylation of c-Abl by PEST-type PTP represents a novel mechanism by which c-Abl activity is regulated.
Related Concept Videos
Microtubule Associated Proteins (MAPs)
Phosphoinositides and PIPs
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Anaphase Promoting Complex
Amplifying Signals via Enzymatic Cascade
The JAK-STAT Signaling Pathway
PI3K/mTOR/AKT Signaling Pathway

