Isolation and determination of PI(4,5)P2 proximal proteins
Ontology highlight
ABSTRACT:
INSTRUMENT(S): LTQ Orbitrap
ORGANISM(S): Homo Sapiens (human)
TISSUE(S): Epithelial Cell
SUBMITTER: 
Yoshikazu Nakamura
LAB HEAD: Yoshikazu nakamura
PROVIDER: PXD031266 | Pride | 2022-03-26
REPOSITORIES: Pride
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Project description:Phosphatase activities on PI(3,4,5)P3 and
PI(3,4)P2
This model describes the action of various phosphatases on
PI(3,4,5)P3 and PI(3,4)P2, in response to a stimulation by EGF. It
contains boolean switches to simulate knock-down and knock-out of
phosphatases as well as inhibition of PI3 kinase.
This model is described in the article:
PTEN Regulates PI(3,4)P2
Signaling Downstream of Class I PI3K
Mouhannad Malek, Anna Kielkowska,
Tamara Chessa, Karen E. Anderson, David Barneda, P?nar Pir,
Hiroki Nakanishi, Satoshi Eguchi, Atsushi Koizumi, Junko Sasaki,
Véronique Juvin, Vladimir Y. Kiselev, Izabella Niewczas,
Alexander Gray, Alexandre Valayer, Dominik Spensberger, Marine
Imbert, Sergio Felisbino, Tomonori Habuchi, Soren Beinke, Sabina
Cosulich, Nicolas Le Novère, Takehiko Sasaki, Jonathan
Clark, Phillip T. Hawkins and Len R. Stephens
Molecular Cell
Abstract:
The PI3K signaling pathway regulates cell growth and
movement and is heavily mutated in cancer. Class I PI3Ks
synthesize the lipid messenger PI(3,4,5)P3. PI(3,4,5)P3 can be
dephosphorylated by 3- or 5-phosphatases, the latter producing
PI(3,4)P2. The PTEN tumor suppressor is thought to function
primarily as a PI(3,4,5)P3 3-phosphatase, limiting activation
of this pathway. Here we show that PTEN also functions as a
PI(3,4)P2 3-phosphatase, both in vitro and in vivo. PTEN is a
major PI(3,4)P2 phosphatase in Mcf10a cytosol, and loss of PTEN
and INPP4B, a known PI(3,4)P2 4-phosphatase, leads to
synergistic accumulation of PI(3,4)P2, which correlated with
increased invadopodia in epidermal growth factor
(EGF)-stimulated cells. PTEN deletion increased PI(3,4)P2
levels in a mouse model of prostate cancer, and it inversely
correlated with PI(3,4)P2 levels across several EGF-stimulated
prostate and breast cancer lines. These results point to a role
for PI(3,4)P2 in the phenotype caused by loss-of-function
mutations or deletions in PTEN.
This model is hosted on
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MODEL1704190000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
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