Open AccessRsu1‐dependent control of PTEN expression is regulated via ATF2 and cJun
Author(s) -
Kim YongChul,
GonzalezNieves Reyda,
Cutler Mary L.
Publication year - 2019
Publication title -
journal of cell communication and signaling
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 44
eISSN - 1873-961X
pISSN - 1873-9601
DOI - 10.1007/s12079-018-00504-4
Subject(s) - pten , integrin linked kinase , microbiology and biotechnology , protein kinase b , phosphorylation , akt1 , signal transduction , integrin , cell adhesion , chemistry , kinase , biology , cancer research , pi3k/akt/mtor pathway , protein kinase a , cell , biochemistry , cyclin dependent kinase 2
The Rsu1 protein contributes to cell adhesion and migration via its association with the adaptor complex of Integrin linked kinase ( I LK), P INCH, and P arvin (IPP), which binds to the cytoplasmic domain of β1 integrins joining integrins to the actin cytoskeleton. Rsu1 binding to PINCH in the IPP complex is required for EGF‐induced adhesion, spreading and migration in MCF10A mammary epithelial cells. In addition, Rsu1 expression inhibits Jun kinase but is necessary for the activation of MKK4 and p38 Map kinase signaling essential for migration in MCF10A cells. The data reported here examines the links between MKK4‐p38‐ATF2 signaling and AKT regulation in MCF10A cells. Ectopic Rsu1 inhibited AKT1 phosphorylation while Rsu1 depletion induced AKT activation and AKT1 phosphorylation of MKK4 on serine 80, blocking MKK4 activity. Rsu1 depletion also reduced the RNA for lipid phosphatase PTEN thus implicating PTEN in modulating levels of activated AKT in these conditions. ChIP analysis of the PTEN promoter revealed that Rsu1 depletion prevented binding of ATF2 to a positive regulatory site in the PTEN promoter and the enhanced binding of cJun to a negatively regulatory PTEN promoter site. These results demonstrate a mechanism by which Rsu1 adhesion signaling alters the balance between MKK4‐p38‐ATF2 and cJun activation thus altering PTEN expression in MCF10A cells.