These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: BCR/abl leads to the constitutive activation of Stat proteins, and shares an epitope with tyrosine phosphorylated Stats.
    Author: Frank DA, Varticovski L.
    Journal: Leukemia; 1996 Nov; 10(11):1724-30. PubMed ID: 8892675.
    Abstract:
    The mechanism by which BCR/abl leads to the transformation of hematopoietic cells is not understood. The introduction of BCR/abl into BaF3 cells, an IL-3-dependent pro-lymphocytic cell line, abrogates the requirement of IL-3 for growth. Given that IL-3 leads to the phosphorylation of Stat proteins, we tested the hypothesis that BCR/abl transformation of hematopoietic cells induces the phosphorylation of Stats. We found that BaF3 cells transformed by either the p190 or p210 forms of BCR/abl possess constitutively phosphorylated Stat1 and Stat5. Phosphorylation of Stat proteins was greater in cells transformed by p190 BCR/abl than in cells transformed by p210 BCR/abl, suggesting that the magnitude of phosphorylation of Stat proteins may play a role in the biological effects of BCR/abl. Expression of BCR/abl containing a mutation (Y177F) that prevents its interaction with GRB2 led to a decrease in the phosphorylation of Stat1 and Stat5. This suggested that GRB2, or its binding site on BCR/abl, may participate in the phosphorylation of Stat proteins. We also observed that the anti-phospho-Stat antibody directly recognized both the p190 and p210 forms of BCR/abl. This indicated that a tyrosine residue that becomes phosphorylated in BCR/abl may share homology with the tyrosine phosphorylation site of Stat1 and Stat5. These findings may have implications for the mechanisms by which BCR/abl interacts with signaling pathways to confer growth factor independence and induce transformation of hematopoietic cells.
    [Abstract] [Full Text] [Related] [New Search]