Tissue transglutaminase mRNA expression in apoptotic cell death
E B Volokhina1, R Hulshof, C Haanen
1Department of Clinical Chemistry, Medisch Spectrum Twente, Hospital Group, P.O. Box 50000, 7500 KA Enschede, The Netherlands.
Apoptosis : an International Journal on Programmed Cell Death
|January 24, 2004
Summary
Tissue transglutaminase messenger RNA (t.TG-mRNA) expression significantly increases with apoptosis. This rise in t.TG-mRNA levels can serve as a reliable marker for detecting and quantifying recent apoptotic cell death.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Tissue transglutaminase (t.TG) is an enzyme crucial for protein cross-linking and maintaining cellular integrity.
- During apoptosis, t.TG is activated and plays a role in the formation of apoptotic bodies.
- Understanding t.TG's role in apoptosis is key to developing new diagnostic markers.
Purpose of the Study:
- To investigate the expression levels of t.TG-mRNA during apoptosis.
- To determine if t.TG-mRNA expression can be used as a quantitative marker for recent apoptosis.
- To assess the reliability and specificity of t.TG-mRNA as an apoptosis biomarker.
Main Methods:
- Real-time RT-PCR (TaqMan based) was employed to measure t.TG-mRNA expression.
- Experiments were conducted on cultured cells (MCF-7, human endothelial cells) and peripheral blood mononuclear cells (PBMCs).
- Apoptosis was induced in vitro, and t.TG-mRNA levels were measured before and after induction.
Main Results:
- TaqMan RT-PCR for t.TG-mRNA was found to be reliable, reproducible, and specific for apoptotic cell death.
- t.TG-mRNA expression increased significantly (up to 20-fold) in response to apoptosis induction in a dose- and time-dependent manner.
- Elevated t.TG-mRNA expression was observed in PBMCs from myelodysplasia patients, correlating with in vivo apoptosis.
Conclusions:
- t.TG-mRNA expression is a significant indicator of apoptosis induction.
- The dose and time-dependent nature of t.TG-mRNA changes supports its utility.
- t.TG-mRNA serves as a valuable trace marker for the detection and quantification of apoptosis.
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