N-myc is frequently activated by proviral insertion in MuLV-induced T cell lymphomas.
We report a new common proviral insertion site in murine leukemia virus-induced T cell lymphomas to be N-myc. Proviral activation of N-myc was found in 35% of independently induced primary tumors. The vast majority of the proviral insertions occur within a small segment of the 3'-untranslated region of the N-myc gene, directly downstream of the protein-encoding domain. This results in an increased level of expression of a truncated N-myc mRNA. Together with the previously shown c-myc activation we now find involvement of myc genes in greater than 75% of the primary T cell lymphomas induced by Moloney murine leukemia virus in C57BL10 and BALB/c mice, and show for the first time that N-myc can be over-expressed by a mechanism other than gene amplification.
van Lohuizen
M
M
Division of Molecular Genetics, Netherlands Cancer Institute, Amsterdam.
Breuer
M
M
Berns
A
A
D000818:Animals; D005786:Gene Expression Regulation; D008223:Lymphoma / Q000235:genetics* / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008979:Moloney murine leukemia virus / Q000302:isolation & purification / Q000502:physiology*; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D009857:Oncogenes; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis* / Q000235:genetics; D016271:Proto-Oncogene Proteins c-myc; D011533:Proviruses / Q000302:isolation & purification / Q000502:physiology*; D011995:Recombination, Genetic; D013601:T-Lymphocytes
D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc