Transforming potential of a myc-containing variant of feline leukemia virus in vitro in early-passage feline cells.
AUTOR(ES)
Bonham, L
RESUMO
We studied a naturally occurring variant of feline leukemia virus (FeLV) in which the oncogene myc has substituted for a portion of the viral structural genes (myc-FeLV). myc-FeLV was rescued by replication in the presence of FeLV as helper, and its biological activity was examined in early-passage feline cells in vitro. Infection of leukocytes from peripheral blood, spleen, or thymus, or of kitten fibroblasts did not immortalize these cells or alter them morphologically. Northern blot (RNA blot) analysis of virion RNA prepared from the supernatant of infected cells demonstrated the 8.2-kilobase genome of FeLV, but did not demonstrate the 5.0-kilobase genome of myc-FeLV. Apparently, the myc-FeLV genome was lost in the absence of the selective pressure of transformation. In contrast, infection of embryonic fibroblasts with myc-FeLV(FeLV) rendered these cells capable of greatly increased, if not infinite, proliferative potential. The cells were morphologically altered compared with controls and were only loosely adherent to the substrate. The cells failed to proliferate in semisolid medium and did not form tumors when inoculated subcutaneously into athymic mice. Blot analyses demonstrated the presence and expression of integrated proviral DNAs of both FeLV and myc-FeLV in these cells. They appear, then, to represent cells partially transformed by infection with myc-FeLV(FeLV). The action of feline v-myc in early-passage cells in vitro was compared to that of avian v-myc.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=255882Documentos Relacionados
- Tumorigenic potential of a myc-containing strain of feline leukemia virus in vivo in domestic cats.
- Derivation of completely cell culture-derived mice from early-passage embryonic stem cells.
- Insertional mutagenesis of flvi-2 in tumors induced by infection with LC-FeLV, a myc-containing strain of feline leukemia virus.
- Transforming variants of the avian myc-containing retrovirus FH3 arise prior to phenotypic selection.
- The simian virus 40 sequences between 0.169 and 0.423 map units are not essential to immortalize early-passage rat embryo cells.