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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Regulation of apoptotic and growth inhibitory activities of C/EBPalpha in different cell lines

Guo-Li Wang1, Xiurong Shi, Elizabeth Salisbury

  • 1Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA.

Experimental Cell Research
|March 4, 2008
PubMed

Insights

CCAAT-enhancer-binding protein alpha (C/EBPalpha) shows differential apoptotic and growth inhibitory activities across cell types. Cyclin D3 is crucial for C/EBPalpha-mediated proliferation inhibition in specific cell lines.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • C/EBPalpha is a transcription factor known to inhibit cell growth and is expressed in various tissues.
  • Understanding the regulatory mechanisms controlling C/EBPalpha activity is crucial for its role in cell proliferation and apoptosis.

Purpose of the Study:

  • To investigate the differential regulation of C/EBPalpha's apoptotic and growth-inhibitory activities in cell lines from different tissues.
  • To identify the molecular mechanisms underlying these differential activities.

Main Methods:

  • Utilized various cell lines (NIH3T3, 3T3-L1, Hep3B2, HEK293) to study C/EBPalpha function.
  • Employed micro-array analysis to identify C/EBPalpha-regulated genes involved in apoptosis.
  • Used C/EBPalpha mutants and manipulated cyclin D3 levels to assess proliferation inhibition.

Main Results:

  • C/EBPalpha exhibited strong pro-apoptotic activity in NIH3T3 cells, but not in 3T3-L1, Hep3B2, or HEK293 cells.
  • Micro-array data revealed C/EBPalpha activates apoptosis signaling genes, including ARL6IP5, in NIH3T3 cells.
  • C/EBPalpha's growth arrest activity in NIH3T3 cells correlated with low cyclin D3 levels and was restored upon cyclin D3 elevation.

Conclusions:

  • The apoptotic and growth inhibitory functions of C/EBPalpha are differentially regulated depending on the cell type.
  • Cooperation between cyclin D3 and C/EBPalpha is essential for inhibiting cell proliferation.
  • ARL6IP5 is identified as a direct target gene of C/EBPalpha and a key mediator of apoptosis.

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