Addition of constitutive c-myc expression to Abelson murine leukemia virus changes the phenotype of the cells transformed by the virus from pre-B-cell lymphomas to plasmacytomas.
Abelson murine leukemia virus (A-MuLV), a retrovirus that expresses the v-abl oncogene, characteristically induces pre-B-cell lymphomas following in vivo infection of BALB/c mice or in vitro infection of suspensions of fetal liver or bone marrow cells. ABL-MYC, a retrovirus that expresses both v-abl and c-myc, induces solely plasmacytomas in BALB/c mice. To investigate how the addition of overexpression of c-myc to that of v-abl accomplishes this dramatic change in the phenotype of the cells transformed by these closely related retroviruses, we utilized helper-free A-MuLV (psi 2) and ABL-MYC (psi 2) in vitro to infect suspensions of cells from different lymphoid tissues and purified immature and purified mature B cells. As expected, A-MuLV(psi 2) induced only pre-B-cell lymphomas in vivo and in vitro when immature B cells were present. ABL-MYC(psi 2), on the other hand, produced only plasmacytomas, even when purified immature B lymphocytes were infected in vitro. Although the A-MuLV(psi 2)-induced pre-B-cell lymphomas express easily detectable levels of c-myc mRNA, maturation into more-mature forms of B lymphocytes is blocked. The constitutively overexpressed c-myc in the ABL-MYC retrovirus abrogates this block, permits maturation of infected immature B cells, and yields transformed plasma cells.
Weissinger
E M
EM
Molecular Genetics Section, National Cancer Institute, Bethesda, Maryland 20892.
Mischak
H
H
Goodnight
J
J
Davidson
W F
WF
Mushinski
J F
JF
D000011:Abelson murine leukemia virus / Q000235:genetics* / Q000472:pathogenicity; D000818:Animals; D001402:B-Lymphocytes / Q000382:microbiology*; D002472:Cell Transformation, Viral / Q000235:genetics*; D003673:Defective Viruses / Q000235:genetics; D015973:Gene Expression Regulation, Leukemic; D016259:Genes, myc; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D010641:Phenotype; D010954:Plasmacytoma / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics
D012333:RNA, Messenger; D012334:RNA, Neoplasm