Next Article in Journal
Poly-γ-Glutamic Acid Induces Apoptosis via Reduction of COX-2 Expression in TPA-Induced HT-29 Human Colorectal Cancer Cells
Previous Article in Journal
In Vitro Cytotoxic Evaluation of MgO Nanoparticles and Their Effect on the Expression of ROS Genes
Article Menu
Issue 4 (April) cover image

Export Article

Open AccessArticle
Int. J. Mol. Sci. 2015, 16(4), 7565-7576; doi:10.3390/ijms16047565

Insulin Induces Phosphorylation of Serine Residues of Translationally Controlled Tumor Protein in 293T Cells

Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans University, Seoul 120-750, Korea
These authors contributed equally to this work.
*
Author to whom correspondence should be addressed.
Academic Editor: Jack A. Schalken
Received: 19 December 2014 / Revised: 22 January 2015 / Accepted: 17 March 2015 / Published: 3 April 2015
(This article belongs to the Section Biochemistry, Molecular and Cellular Biology)
View Full-Text   |   Download PDF [927 KB, uploaded 3 April 2015]   |  

Abstract

Insulin induces the activation of Na,K-ATPase while translationally controlled tumor protein (TCTP) inhibits this enzyme and the associated pump activity. Because binding of insulin with its membrane receptor is known to mediate the phosphorylation of multiple intracellular proteins, phosphorylation of TCTP by insulin might be related to the sodium pump regulation. We therefore examined whether insulin induces TCTP phosphorylation in embryonic kidney 293T cells. Using immunoprecipitation and Western blotting, we found that insulin phosphorylates serine (Ser) residues of TCTP. Following fractionation of the insulin-treated cells into cytosol and membrane fractions, phosphorylated TCTP at its Ser residue (p-Ser-TCTP) was detected exclusively in the cytosolic part and not in the membrane fraction. Phosphorylation of TCTP reached maximum in about 10 min after insulin treatment in 293T cells. In studies of cell-type specificity of insulin-mediated phosphorylation of TCTP, insulin did not phosphorylate TCTP in HeLa cells. Computational prediction and immunoprecipitation using several constructs having Ser to Ala mutation at potential p-Ser sites of TCTP revealed that insulin phosphorylated the serine-9 and -15 residues of TCTP. Elucidations of how insulin-mediated TCTP phosphorylation promotes Na,K-ATPase activation, may offer potential therapeutic approaches to diseases associated with vascular activity and sodium pump dysregulation. View Full-Text
Keywords: insulin; Na,K-ATPase; phosphorylation; serine; TCTP insulin; Na,K-ATPase; phosphorylation; serine; TCTP
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Maeng, J.; Kim, M.; Lee, H.; Lee, K. Insulin Induces Phosphorylation of Serine Residues of Translationally Controlled Tumor Protein in 293T Cells. Int. J. Mol. Sci. 2015, 16, 7565-7576.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top