Deletion of the Src homology 3 domain and C-terminal proline-rich sequences in Bcr-Abl prevents Abl interactor 2 degradation and spontaneous cell migration and impairs leukemogenesis.
J Biol Chem 2001;
276:28954-60. [PMID:
11387320 DOI:
10.1074/jbc.m101170200]
[Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The hematopoietic cells from patients with Bcr-Abl-positive chronic myelogenous leukemia exhibit multiple abnormalities of cytoskeletal function. The molecular events leading to these abnormalities are not fully understood. Previously we showed that Bcr-Abl elicits ubiquitin-dependent degradation of Abl interactor proteins. Because recent studies have suggested a role of Abl interactor proteins in the pathway that regulates cytoskeletal function, we investigated whether mutations in Bcr-Abl that interfere with the signaling to Abl interactor proteins affect its leukemogenic activity. We report here that the Src homology 3 domain and C-terminal proline-rich sequences of Bcr-Abl are required for its binding to Abl interactor 2 as well as for the induction of Abl interactor 2 degradation. Although the deletion of these regions did not affect the ability of the mutant Bcr-Abl to transform hematopoietic cells to growth factor independence, it abrogated its ability to stimulate spontaneous cell migration on fibronectin-coated surfaces. Furthermore, the mutant Bcr-Abl, defective in binding to Abl interactor 2 and inducing its degradation, failed to induce chronic myelogenous leukemia-like disease in mouse. These results are consistent with a role of Abl interactor proteins in the regulation of cytoskeletal function as well as in the pathogenesis of Bcr-Abl-induced leukemogenesis.
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