Identification of an oncogenic form of the thrombopoietin receptor MPL using retrovirus-mediated gene transfer.
Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3-dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5.
Onishi
M
M
Department of Cell Signaling, DNAX Research Institute of Molecular and Cellular Biology, Palo Alto, CA 94304, USA.
Mui
A L
AL
Morikawa
Y
Y
Cho
L
L
Kinoshita
S
S
Nolan
G P
GP
Gorman
D M
DM
Miyajima
A
A
Kitamura
T
T
D000818:Animals; D001483:Base Sequence; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002455:Cell Division; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000378:metabolism; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D053614:Janus Kinase 2; D051379:Mice; D008894:Milk Proteins; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins; D009857:Oncogenes; D019000:Phosphotyrosine / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism / Q000502:physiology*; D019908:Proto-Oncogene Proteins c-raf; D018121:Receptors, Cytokine; D053628:Receptors, Thrombopoietin; D012190:Retroviridae / Q000235:genetics; D050796:STAT3 Transcription Factor; D050799:STAT5 Transcription Factor; D015398:Signal Transduction; D013329:Structure-Activity Relationship; D053634:TYK2 Kinase; D013926:Thrombopoietin / Q000502:physiology; D015534:Trans-Activators / Q000378:metabolism
D004268:DNA-Binding Proteins; D008894:Milk Proteins; D009363:Neoplasm Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D018121:Receptors, Cytokine; D053628:Receptors, Thrombopoietin; D050796:STAT3 Transcription Factor; D050799:STAT5 Transcription Factor; C494087:Stat3 protein, mouse; D015534:Trans-Activators; C082218:MPL protein, human; D019000:Phosphotyrosine; D013926:Thrombopoietin; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; C507926:Jak2 protein, mouse; D053614:Janus Kinase 2; D053634:TYK2 Kinase; C499356:Tyk2 protein, mouse; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D017871:Calcium-Calmodulin-Dependent Protein Kinases