[Changes of phenotypes associated with activated Src by overexpressed PTPalpha in NIH3T3 cells]
Jin-Song Yang1, Xin-Min Zheng, Shi-Shu Chen
1Department of Biochemistry, Lab of Molecular Biology and Research Center for Human Gene Therapy, Shanghai Second Medical University, Shanghai 200025, China. sschen@shsmu.edu.cn
Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao Acta Biochimica Et Biophysica Sinica
|May 15, 2002
Summary
Protein tyrosine phosphatase alpha (PTPalpha) induction initiated NIH3T3 cell transformation. This transformation is linked to activated Src kinase, suggesting PTPalpha
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Context:
- Investigating tumor formation mechanisms requires understanding cellular phenotype changes.
- NIH3T3 cells provide a model for studying inducible gene expression and its consequences.
Purpose:
- To elucidate the role of protein tyrosine phosphatase alpha (PTPalpha) in initiating cellular transformation.
- To explore the association between PTPalpha expression, Src kinase activity, and malignant phenotype changes.
Summary:
- NIH3T3 cells with inducible PTPalpha expression showed increased PTPalpha levels and Src kinase activity after 24-hour induction.
- Src kinase activity was elevated due to dephosphorylation of pTyr(527) in its C-tail, mediated by PTPalpha.
- Malignant cellular phenotypes were observed, confirmed by flow cytometry and electron microscopy.
Impact:
- PTPalpha induction can initiate NIH3T3 cell transformation, potentially through Src kinase activation.
- This study provides insights into the molecular mechanisms underlying PTPalpha-mediated oncogenesis.
- Findings contribute to understanding the early events in tumor formation and potential therapeutic targets.
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