Related Experiment Videos
A novel transglutaminase activator forms a complex with type 1 transglutaminase
Michael T Sturniolo1, Roshantha A S Chandraratna, Richard L Eckert
1Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 2109 Adelbert Road, Cleveland, OH 44106-4970, USA.
Oncogene
|April 23, 2005
Summary
The novel protein TIG3 activates type I transglutaminase (TG1) by forming a complex, leading to TG1-mediated keratinocyte cell death. This TG1 activity is essential for the biological effects of TIG3.
Area of Science:
- Biochemistry
- Cell Biology
- Dermatology
Background:
- Type I transglutaminase (TG1) is crucial for keratinocyte differentiation and epidermal barrier formation.
- A novel protein, TIG3, was previously found to increase TG1 activity and induce keratinocyte cell death.
- The precise mechanism by which TIG3 activates TG1 remained unknown.
Purpose of the Study:
- To elucidate the molecular mechanism underlying TIG3-mediated activation of type I transglutaminase.
- To confirm the role of TG1 activity in the biological responses induced by TIG3 expression.
Main Methods:
- Co-immunoprecipitation assays to detect TIG3-transglutaminase complex formation.
- Treatment of TIG3-expressing cells with monodansyl cadaverine, a competitive TG1 substrate.
Main Results:
- Full-length TIG3 forms a stable complex with type I transglutaminase.
- Monodansyl cadaverine treatment significantly reduced the TIG3-dependent cellular response.
- These results indicate that TG1 is a key mediator of TIG3's action.
Conclusions:
- TIG3 directly interacts with type I transglutaminase, forming a protein complex.
- This complex formation leads to the activation of TG1's enzymatic activity.
- TG1 enzymatic activity is indispensable for the TIG3-induced biological outcomes, including keratinocyte cell death.