TY - JOUR
T1 - Inhibition of 14-3-3 binding to Rictor of mTORC2 for Akt phosphorylation at Ser473 is regulated by selenoprotein W
AU - Jeon, Yeong Ha
AU - Park, Yong Hwan
AU - Kwon, Joon Hyun
AU - Lee, Jea Hwang
AU - Kim, Ick Young
N1 - Funding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) , which was funded by the Ministry of Education, Science and Technology ( 2011-0009136 ).
PY - 2013/10
Y1 - 2013/10
N2 - 14-3-3 reduces cell proliferation by inhibiting the activity of proteins involved in the signaling pathway that includes Akt kinase. Activation of Akt is enhanced by activating the mammalian target of rapamycin complex 2 (mTORC2). 14-3-3 is also a negative regulator of the mTORC2/Akt pathway, by interacting with a component of mTORC2. Recently, we reported that selenoprotein W (SelW) regulated the interaction between 14-3-3 and its target protein, CDC25B. Here, we show that the binding of Rictor, a component of mTORC2, to 14-3-3, is regulated by the interaction of 14-3-3 with SelW. When SelW was down-regulated, mTORC2-dependent phosphorylation of Akt at Ser473 was decreased. However, the phosphorylation of Thr308 was not affected. The interaction of Rictor with 14-3-3 was increased in SelW-knockdown cells, as compared to control cells. SelW-knockdown cells were also more sensitive to DNA damage induced by etoposide, than control cells. This phenomenon was due to the decreased phosphorylation of Akt at Ser473. We also found that ectopic expression of SelW(U13C) reduced the interaction between Rictor and 14-3-3, leading to Akt phosphorylation at Ser473. Taken together, these findings demonstrate that SelW activates the mTORC2/Akt pathway for Akt phosphorylation at Ser473, by interrupting the binding of Rictor to 14-3-3.
AB - 14-3-3 reduces cell proliferation by inhibiting the activity of proteins involved in the signaling pathway that includes Akt kinase. Activation of Akt is enhanced by activating the mammalian target of rapamycin complex 2 (mTORC2). 14-3-3 is also a negative regulator of the mTORC2/Akt pathway, by interacting with a component of mTORC2. Recently, we reported that selenoprotein W (SelW) regulated the interaction between 14-3-3 and its target protein, CDC25B. Here, we show that the binding of Rictor, a component of mTORC2, to 14-3-3, is regulated by the interaction of 14-3-3 with SelW. When SelW was down-regulated, mTORC2-dependent phosphorylation of Akt at Ser473 was decreased. However, the phosphorylation of Thr308 was not affected. The interaction of Rictor with 14-3-3 was increased in SelW-knockdown cells, as compared to control cells. SelW-knockdown cells were also more sensitive to DNA damage induced by etoposide, than control cells. This phenomenon was due to the decreased phosphorylation of Akt at Ser473. We also found that ectopic expression of SelW(U13C) reduced the interaction between Rictor and 14-3-3, leading to Akt phosphorylation at Ser473. Taken together, these findings demonstrate that SelW activates the mTORC2/Akt pathway for Akt phosphorylation at Ser473, by interrupting the binding of Rictor to 14-3-3.
KW - 14-3-3
KW - Akt
KW - MTOR
KW - Rictor
KW - Selenoprotein W
UR - http://www.scopus.com/inward/record.url?scp=84879469402&partnerID=8YFLogxK
U2 - 10.1016/j.bbamcr.2013.05.005
DO - 10.1016/j.bbamcr.2013.05.005
M3 - Article
C2 - 23680186
AN - SCOPUS:84879469402
SN - 0167-4889
VL - 1833
SP - 2135
EP - 2142
JO - Biochimica et Biophysica Acta - Molecular Cell Research
JF - Biochimica et Biophysica Acta - Molecular Cell Research
IS - 10
ER -