osterbar at ix.netcom.com wrote:
>Are there cellular fuctions that are based on viral proteins (are
>there mitochondrial viruses?). Does anybody know of retrovirus
>that effect germ cells? Along this line, are oncogenes products
>of our own misdirected genes or perhaps in our evolutionary past a
>virus found an unique way to propogate.
The retrovirus mouse mammary tumour virus infects germ line cells
and is transmitted vertically.
Many oncogenes of simple retroviruses appear to have been transduced
from normal cellular genes, placing them under the control of the
viral LTR, resulting in overexpression when a host cell is infected
by the virus.
Some oncogenes, for example the tax gene of human T lymphotropic virus
type I, do not appear to have a normal cellular homologue and
probably evolved as a viral regulatory protein which, in the context
of the virus' replication strategy, contributes to oncogenesis.
Adrian W Philbey
Elizabeth Macarthur Agricultural Institute
Camden NSW 2570
nswema05 at angis.su.oz.au