Abstract
Phospholipase C-γ (PLC-γ) activity increases rapidly upon activation of many receptor tyrosine kinases. To clarify the mechanism of PLC-γ regulation we measured the effect of the intracellular domain of the epidermal growth factor receptor (EGFR-ID), the core tyrosine kinase domain that lacks self-phosphorylation sites (EGFR-KD) and the core self-phosphorylation sites alone (EGFR-CT) on PLC-γ activity in vitro. Tyrosine phosphorylation of PLC-γ was catalyzed by either the cytoplasmic domain or the kinase domain of the EGFR but PLC-γ activity was increased only by the complete cytoplasmic domain of the receptor. Addition of the self-phosphorylation domain alone or in conjunction with the kinase domain did not increase PLC-γ activity. However, both the cytoplasmic domain of the EGFR and the carboxy terminal tail of the EGFR coimmunoprecipitate with PLC-γ. These results suggest that both tyrosine phosphorylation of PLC-γ and binding of PLC-γ to a tyrosine phosphorylated protein are coordinately required for enzyme activation.
| Original language | English |
|---|---|
| Pages (from-to) | 347-355 |
| Number of pages | 9 |
| Journal | Journal of Biochemistry, Molecular Biology and Biophysics |
| Volume | 5 |
| Issue number | 5 |
| State | Published - 1 Dec 2001 |
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Keywords
- Epidermal growth factor receptor
- Phospholipase C
- Tyrosine kinase
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Analysis of phospholipase C-γ activation by a truncated receptor tyrosine kinase in vitro. / Vega, Quinn.
In: Journal of Biochemistry, Molecular Biology and Biophysics, Vol. 5, No. 5, 01.12.2001, p. 347-355.Research output: Contribution to journal › Article
TY - JOUR
T1 - Analysis of phospholipase C-γ activation by a truncated receptor tyrosine kinase in vitro
AU - Vega, Quinn
PY - 2001/12/1
Y1 - 2001/12/1
N2 - Phospholipase C-γ (PLC-γ) activity increases rapidly upon activation of many receptor tyrosine kinases. To clarify the mechanism of PLC-γ regulation we measured the effect of the intracellular domain of the epidermal growth factor receptor (EGFR-ID), the core tyrosine kinase domain that lacks self-phosphorylation sites (EGFR-KD) and the core self-phosphorylation sites alone (EGFR-CT) on PLC-γ activity in vitro. Tyrosine phosphorylation of PLC-γ was catalyzed by either the cytoplasmic domain or the kinase domain of the EGFR but PLC-γ activity was increased only by the complete cytoplasmic domain of the receptor. Addition of the self-phosphorylation domain alone or in conjunction with the kinase domain did not increase PLC-γ activity. However, both the cytoplasmic domain of the EGFR and the carboxy terminal tail of the EGFR coimmunoprecipitate with PLC-γ. These results suggest that both tyrosine phosphorylation of PLC-γ and binding of PLC-γ to a tyrosine phosphorylated protein are coordinately required for enzyme activation.
AB - Phospholipase C-γ (PLC-γ) activity increases rapidly upon activation of many receptor tyrosine kinases. To clarify the mechanism of PLC-γ regulation we measured the effect of the intracellular domain of the epidermal growth factor receptor (EGFR-ID), the core tyrosine kinase domain that lacks self-phosphorylation sites (EGFR-KD) and the core self-phosphorylation sites alone (EGFR-CT) on PLC-γ activity in vitro. Tyrosine phosphorylation of PLC-γ was catalyzed by either the cytoplasmic domain or the kinase domain of the EGFR but PLC-γ activity was increased only by the complete cytoplasmic domain of the receptor. Addition of the self-phosphorylation domain alone or in conjunction with the kinase domain did not increase PLC-γ activity. However, both the cytoplasmic domain of the EGFR and the carboxy terminal tail of the EGFR coimmunoprecipitate with PLC-γ. These results suggest that both tyrosine phosphorylation of PLC-γ and binding of PLC-γ to a tyrosine phosphorylated protein are coordinately required for enzyme activation.
KW - Epidermal growth factor receptor
KW - Phospholipase C
KW - Tyrosine kinase
UR - http://www.scopus.com/inward/record.url?scp=0035761725&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0035761725
VL - 5
SP - 347
EP - 355
JO - Journal of Biochemistry, Molecular Biology and Biophysics
JF - Journal of Biochemistry, Molecular Biology and Biophysics
SN - 1025-8140
IS - 5
ER -