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Updated: Jul 18, 2026

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions
10:58

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions

Published on: July 27, 2017

Mapping the phosphoinositide-binding site on chick cofilin explains how PIP2 regulates the cofilin-actin interaction

Vitaliy Y Gorbatyuk1, Neil J Nosworthy, Scott A Robson

  • 1Department of Molecular, Microbial and Structural Biology, University of Connecticut Health Center, Farmington, Connecticut 06032, USA.

Molecular Cell
|November 23, 2006
PubMed

Insights

Researchers identified how phosphoinositides (PIs) bind to cofilin, revealing a unique site that regulates actin dynamics. This discovery clarifies cofilin

Area of Science:

  • Cell Biology
  • Biochemistry
  • Molecular Biology

Background:

  • Cofilin is crucial for actin dynamics, severing filaments and promoting monomer dissociation.
  • The mechanism of phosphoinositide (PI) inhibition of cofilin-actin interaction remains unclear.

Purpose of the Study:

  • To determine the structural basis of phosphoinositide (PI) binding to cofilin.
  • To elucidate how PIs regulate cofilin's interaction with actin.

Main Methods:

  • Determined the structure of chick cofilin.
  • Utilized NMR chemical shift mapping.
  • Employed structure-directed mutagenesis.

Main Results:

  • Unambiguously located the PI recognition site on cofilin.
  • Identified a unique binding site requiring both PI acyl chain and head group.
  • Demonstrated that PI binding is independent of cofilin phosphorylation.

Conclusions:

  • The identified PI recognition site on cofilin mediates interaction with membrane-bound PIs.
  • PI binding to cofilin inhibits its interaction with actin and actin-interacting protein 1.
  • This interaction facilitates the spatiotemporal regulation of cofilin activity in cellular processes.

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