Changes in the proteome associated with the action of Bcr-Abl tyrosine kinase are not related to transcriptional regulation.
Chronic myeloid leukemia (CML) is a hematopoietic stem cell disease, the hallmark of which is the Bcr-Abl protein tyrosine kinase (PTK). Without intervention the disease progresses from a benign chronic phase to a rapidly fatal blast crisis. To identify the molecular mechanisms underlying disease progression we used two-dimensional gel electrophoresis on a model we have previously described using the expression of a conditional mutant of Bcr-Abl PTK in a multipotent stem cell line, FDCP-Mix. Long term exposure of FDCP-Mix cells to Bcr-Abl mimics disease progression in CML. Four major differences were observed as a consequence of long term exposure to the Bcr-Abl PTK compared with cells exposed short term. The proteins were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry-generated peptide mass fingerprint data and liquid chromatography-tandem mass spectrometry-generated sequence information. Leukotriene A4 hydrolase, an enzyme known to be deregulated in CML, was found to be up-regulated. Annexin VI, vacuolar ATP synthase catalytic subunit A, and mortalin were found to be down-regulated. Poly(A) PCR cDNA analysis showed there was no correlation between the protein expression changes and mRNA levels. Western blot analysis also indicated no change in the levels of mortalin or leukotriene A4 hydrolase, indicating that post-translational events may modify protein content of the specific spots. Leukotriene B4 levels (product of leukotriene A4 hydrolase) were, however, reduced in cells exposed long term to Bcr-Abl activity. This study demonstrates the potential of proteomic analysis to define novel effects of oncogenes.
Smith
Duncan L
DL
Leukaemia Research Fund Cellular Development Unit, Department of Biomolecular Sciences, University of Manchester Institute of Science and Technology, Manchester, United Kingdom.
Evans
Caroline A
CA
Pierce
Andrew
A
Gaskell
Simon J
SJ
Whetton
Anthony D
AD
D000818:Animals; D017317:Annexin A6 / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D004851:Epoxide Hydrolases / Q000235:genetics / Q000378:metabolism; D016044:Fusion Proteins, bcr-abl; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D020543:Proteome; D014158:Transcription, Genetic; D025262:Vacuolar Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism
D017317:Annexin A6; D018840:HSP70 Heat-Shock Proteins; D020543:Proteome; C080352:mortalin; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl; D004851:Epoxide Hydrolases; D025262:Vacuolar Proton-Translocating ATPases; C043134:leukotriene A4 hydrolase