Role of cdc25 Phosphatases in Cellular Immortalization.
Abstract
The goal of this proposal is to study the potential role of tyrosine phosphorylation-dependent checkpoint and especially the cdc25 phosphatase family of cyclin dependent kinase (CDK) activators in cellular immortalization. We have shown that cdc25 phosphatases did in fact extend the normal mammary epithelial cells life span, but do not immortalize them. The effect was most prominent with cdc25A and cdc25B phosphatases. Cdc25C phosphatase' had less effect on HMEC life span. Experiments with catalytically inactive cdc25A mutant show that phosphatase activity of cdc25A is essential for the life span extension. Our experiments shows that telomerase is not activated by cdc25A expression in normal human cells, suggesting that cdc25 most likely affect Ml. but not M2 checkpoints.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1999
- Accession Number
- ADA369304
Entities
People
- Konstantin I. Galaktionov
Organizations
- Baylor College of Medicine