Interaction between two adapter proteins, PAG and EBP50: a possible link between membrane rafts and actin cytoskeleton

FEBS Lett. 2001 Oct 26;507(2):133-6. doi: 10.1016/s0014-5793(01)02955-6.


Phosphoprotein associated with GEMs (PAG), also known as Csk-binding protein (Cbp), is a broadly expressed palmitoylated transmembrane adapter protein found in membrane rafts, also called GEMs (glycosphingolipid-enriched membrane microdomains). PAG is known to bind and activate the essential regulator of Src-family kinases, cytoplasmic protein tyrosine kinase Csk. In the present study we used the yeast 2-hybrid system to search for additional proteins which might bind to PAG. We have identified the abundant cytoplasmic adapter protein EBP50 (ezrin/radixin/moesin (ERM)-binding phosphoprotein of 50 kDa), also known as NHERF (Na(+)/H(+) exchanger regulatory factor), as a specific PAG-binding partner. The interaction involves the C-terminal sequence (TRL) of PAG and N-terminal PDZ domain(s) of EBP50. As EBP50 is known to interact via its C-terminal domain with the ERM-family proteins, which in turn bind to actin cytoskeleton, the PAG-EBP50 interaction may be important for connecting membrane rafts to the actin cytoskeleton.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / metabolism*
  • Adaptor Proteins, Signal Transducing
  • Animals
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Fractionation
  • Cell Line
  • Cytoskeleton / metabolism*
  • Dogs
  • Humans
  • Jurkat Cells
  • Membrane Microdomains / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Plasmids
  • Sodium-Hydrogen Exchangers*


  • Actins
  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Membrane Proteins
  • PAG1 protein, human
  • Phosphoproteins
  • Sodium-Hydrogen Exchangers
  • sodium-hydrogen exchanger regulatory factor