Biochem Biophys Res Commun 2004,
PMID: 15351743
Maeda, Kengo; Murakami, Hideki; Yoshida, Reiko; Ichihara, Masatoshi; Abe, Akihiro; Hirai, Makoto; Murohara, Toyoaki; Takahashi, Masahide
Grb2-associated binder-1 (Gab1) is a docking protein closely related to insulin receptor substrates. We previously reported that tyrosine 1062 in RET receptor tyrosine kinase activated by glial cell line-derived neurotrophic factor (GDNF) represents a binding site for the Shc-Grb2-Gab1 complex, and that the p85 subunit of phosphatidylinositol 3-kinase (PI3K) and SHP2 tyrosine phosphatase is associated with Gab1 in GDNF-treated cells. In the present study, we further analyzed the physiological roles of Gab1 downstream of RET, using Gab1 mutants that lack the binding sites for PI3K (Gab1 PI3K-m) or SHP-2 (Gab1 SHP2-m). Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation. Furthermore, expression of Gab1 PI3K-m, but not Gab1 SHP2-m, in TT human medullary thyroid carcinoma cells expressing RET with a multiple endocrine neoplasia 2A mutation enhanced cytochrome c release, and apoptosis induced by etoposide, suggesting that PI3K is involved in survival of TT cells via a mitochondrial pathway. These findings demonstrated that coupling of Gab1 to PI3K is important for biological responses in RET-expressing cells.
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Text Mining Data
Erk ⊣ SHP2-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1
SHP2-m partially
impaired Erk activation
"
Akt ⊣ Erk: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Akt ⊣ PI3K-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Akt ⊣ SHP2-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
GDNF ⊣ Erk: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
GDNF ⊣ SHP2-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Rac1 ⊣ Erk: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Rac1 ⊣ PI3K-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Rac1 ⊣ SHP2-m: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Akt → GDNF: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Rac1 → GDNF: "
Expression of Gab1 PI3K-m in SK-N-MC human primitive neuroectodermal tumor cells expressing wild-type RET markedly impaired Akt phosphorylation, Rac1 activation, and lamellipodia formation that were induced by GDNF whereas expression of Gab1 SHP2-m partially impaired Erk activation
"
Manually curated Databases
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
IRS2 (IRS2)
→
RET9/GFRalpha1/GDNF/SHC/GAB1/Grb2 complex (RET-GFRA1-GDNF-SHC1-GRB2-GAB1)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
IRS2 (IRS2)
→
PI3K complex (PIK3CA-PIK3R1)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
RET9/GFRalpha1/GDNF/SHC/GAB1/Grb2 complex (RET-GFRA1-GDNF-SHC1-GRB2-GAB1)
→
PI3K complex (PIK3CA-PIK3R1)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
RET51/GFRalpha1/GDNF/SHC/GAB1/Grb2 complex (RET-GFRA1-GDNF-SHC1-GRB2-GAB1)
→
IRS2 (IRS2)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
RET51/GFRalpha1/GDNF/SHC/GAB1/Grb2 complex (RET-GFRA1-GDNF-SHC1-GRB2-GAB1)
→
PI3K complex (PIK3CA-PIK3R1)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
IRS2 (IRS2)
→
PI3K complex (PIK3CA-PIK3R1)
(modification, activates)
Evidence: mutant phenotype, assay, physical interaction
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
RAC1/GDP complex (RAC1)
→
RAC1/GTP complex (RAC1)
(modification, collaborate)
Evidence: assay, other species
-
NCI Pathway Database Signaling events regulated by Ret tyrosine kinase:
RAC1/GDP complex (RAC1)
→
PI3K complex (PIK3CA-PIK3R1)
(modification, collaborate)
Evidence: assay, other species
In total, 39 gene pairs are associated to this article in curated databases