Role of tyrosine phosphorylation in radiation-induced activation of c-jun protooncogene in human lymphohematopoietic precursor cells.
We examined the effects of ionizing radiation on c-jun expression in human lymphohematopoietic precursors. Radiation exposure increased the level of c-jun transcripts in a dose- and time-dependent manner, providing direct evidence that ionizing radiation can activate c-jun protooncogene in human lymphohematopoietic precursors. Notable gamma-rays failed to induce c-jun expression in cells pretreated with herbimycin, and the use of cycloheximide did not overcome the inhibitory effects of herbimycin. The lack of c-jun signal in herbimycin-treated cells was not due to nonspecific damage to the distal protein kinase C signaling pathway. Thus, protein tyrosine kinase activation precedes and perhaps mandates radiation-induced activation of c-jun protooncogene expression in human lymphohematopoietic precursors.
Chae
H P
HP
Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota, Minneapolis 55455.
Jarvis
L J
LJ
Uckun
F M
FM
D001402:B-Lymphocytes / Q000187:drug effects / Q000502:physiology; D002051:Burkitt Lymphoma / Q000235:genetics; D004789:Enzyme Activation / Q000528:radiation effects; D015672:Erythroid Precursor Cells / Q000502:physiology; D015973:Gene Expression Regulation, Leukemic / Q000235:genetics / Q000528:radiation effects*; D016758:Genes, jun / Q000235:genetics / Q000528:radiation effects*; D006412:Hematopoietic Stem Cells / Q000502:physiology / Q000528:radiation effects*; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute / Q000235:genetics; D007951:Leukemia, Myeloid / Q000235:genetics; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism / Q000528:radiation effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism*
D012333:RNA, Messenger; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases