TY - JOUR
T1 - Phosphatidylinositol-4,5-bisphosphate regulates epidermal growth factor receptor activation
AU - Michailidis, Ioannis E.
AU - Rusinova, Radda
AU - Georgakopoulos, Anastasios
AU - Chen, Yibang
AU - Iyengar, Ravi
AU - Robakis, Nikolaos K.
AU - Logothetis, Diomedes E.
AU - Baki, Lia
N1 - Funding Information:
This work was supported by a National Institutes of Health grant (HL-59949) to DEL. Support for RI and YC was provided by NIH grant DK-38761. We would like to thank Heikki Vaananen, Sophia Gruszecki, Samantha Lee, and Dr. Mei Zhang for excellent technical assistance, Drs. Pietro DeCamilli (Yale University, CT) for the gift of synaptojanin, and Drs. Show-Ling Shyng and Colin Nichols (Oregon Health and Science University, OR, USA and Washington University, MO, USA) for the gift of PI(5)P kinase. We thank Dr. Qi Zhao for help with the analysis of the FACS data. We would also like to thank Drs. Giorgos Panayotou (Fleming Institute, Athens, Greece), Mitchell Goldfarb (Hunter College, NY, USA), Michael Ehlers (Duke Neurobiology, NC, USA), Julia Sable (Columbia University, NY, USA), Tibor Rohacs (UMDNJ), Stuart Aaronson (Department of Oncological Sciences, MSSM) and the Logothetis laboratory members for insightful discussions and comments on the manuscript.
PY - 2011/3
Y1 - 2011/3
N2 - Phosphatidylinositol-4,5-bisphosphate [PI(4,5)P 2 or PIP 2] is a direct modulator of a diverse array of proteins in eukaryotic cells. The functional integrity of transmembrane proteins, such as ion channels and transporters, is critically dependent on specific interactions with PIP 2 and other phosphoinositides. Here, we report a novel requirement for PIP 2 in the activation of the epidermal growth factor receptor (EGFR). Down-regulation of PIP 2 levels either via pharmacological inhibition of PI kinase activity, or via manipulation of the levels of the lipid kinase PIP5K1α and the lipid phosphatase synaptojanin, reduced EGFR tyrosine phosphorylation, whereas up-regulation of PIP 2 levels via overexpression of PIP5K1α had the opposite effect. A cluster of positively charged residues in the juxtamembrane domain (basic JD) of EGFR is likely to mediate binding of EGFR to PIP 2 and PIP 2-dependent regulation of EGFR activation. A peptide mimicking the EGFR juxtamembrane domain that was assayed by surface plasmon resonance displayed strong binding to PIP 2. Neutralization of positively charged amino acids abolished EGFR/PIP 2 interaction in the context of this peptide and down-regulated epidermal growth factor (EGF)-induced EGFR auto-phosphorylation and EGF-induced EGFR signaling to ion channels in the context of the full-length receptor. These results suggest that EGFR activation and downstream signaling depend on interactions of EGFR with PIP 2 and point to the basic JD's critical involvement in these interactions. The addition of this very different class of membrane proteins to ion channels and transporters suggests that PIP 2 may serve as a general modulator of the activity of many diverse eukaryotic transmembrane proteins through their basic JDs.
AB - Phosphatidylinositol-4,5-bisphosphate [PI(4,5)P 2 or PIP 2] is a direct modulator of a diverse array of proteins in eukaryotic cells. The functional integrity of transmembrane proteins, such as ion channels and transporters, is critically dependent on specific interactions with PIP 2 and other phosphoinositides. Here, we report a novel requirement for PIP 2 in the activation of the epidermal growth factor receptor (EGFR). Down-regulation of PIP 2 levels either via pharmacological inhibition of PI kinase activity, or via manipulation of the levels of the lipid kinase PIP5K1α and the lipid phosphatase synaptojanin, reduced EGFR tyrosine phosphorylation, whereas up-regulation of PIP 2 levels via overexpression of PIP5K1α had the opposite effect. A cluster of positively charged residues in the juxtamembrane domain (basic JD) of EGFR is likely to mediate binding of EGFR to PIP 2 and PIP 2-dependent regulation of EGFR activation. A peptide mimicking the EGFR juxtamembrane domain that was assayed by surface plasmon resonance displayed strong binding to PIP 2. Neutralization of positively charged amino acids abolished EGFR/PIP 2 interaction in the context of this peptide and down-regulated epidermal growth factor (EGF)-induced EGFR auto-phosphorylation and EGF-induced EGFR signaling to ion channels in the context of the full-length receptor. These results suggest that EGFR activation and downstream signaling depend on interactions of EGFR with PIP 2 and point to the basic JD's critical involvement in these interactions. The addition of this very different class of membrane proteins to ion channels and transporters suggests that PIP 2 may serve as a general modulator of the activity of many diverse eukaryotic transmembrane proteins through their basic JDs.
KW - EGF receptor
KW - PIP2
KW - Phosphorylation
KW - Plasma membrane
KW - Signaling
UR - http://www.scopus.com/inward/record.url?scp=79953753353&partnerID=8YFLogxK
U2 - 10.1007/s00424-010-0904-3
DO - 10.1007/s00424-010-0904-3
M3 - Article
C2 - 21107857
AN - SCOPUS:79953753353
SN - 0031-6768
VL - 461
SP - 387
EP - 397
JO - Pflugers Archiv European Journal of Physiology
JF - Pflugers Archiv European Journal of Physiology
IS - 3
ER -