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Updated: Jul 17, 2026

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
10:52

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation

Published on: January 6, 2016

STIM1: a novel phosphoprotein located at the cell surface

S S Manji1, N J Parker, R T Williams

  • 1Department of Paediatrics, The University of Melbourne, Parkville, Victoria, Australia. manjis@cryptic.rch.unimelb.edu.au

Biochimica Et Biophysica Acta
|September 27, 2000
PubMed

Insights

Stromal interaction molecule 1 (STIM1) acts as a tumor suppressor gene, inhibiting growth in various cancer cell lines. This protein is found on the cell surface and is modified through phosphorylation and glycosylation.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Cell Biology

Background:

  • STIM1 is identified as a novel candidate tumor suppressor gene.
  • It maps to human chromosome region 11p15.5, a locus frequently altered in malignancies.
  • STIM1 overexpression induces growth arrest in rhabdoid tumor, rhabdomyosarcoma, and myoblast cell lines.

Purpose of the Study:

  • To investigate the cellular localization and characteristics of STIM1.
  • To confirm the role of STIM1 as a potential tumor suppressor.
  • To explore post-translational modifications of STIM1.

Main Methods:

  • Immunofluorescence and cell surface biotinylation using specific antibodies.
  • Western blot analysis for protein expression.
  • Analysis of post-translational modifications (phosphorylation, glycosylation).

Main Results:

  • STIM1 is localized to the cell surface of K562 cells.
  • The 90-kDa STIM1 protein is ubiquitously expressed in human cells and tumor lines.
  • Evidence of post-translational modifications, including serine-predominant phosphorylation and N-linked glycosylation, was found.

Conclusions:

  • STIM1 functions as a tumor growth suppressor.
  • STIM1 is a ubiquitously expressed, cell-surface phosphoprotein with regulatory potential.
  • STIM1 undergoes post-translational modifications, suggesting complex regulation.

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