The transfection of several DNAs, containing oncogenes ras, src, fes or fps, into
rat 3Y1 cells invariably induced the neosynthesis of sialosylparagloboside (SPG; IV3
alpha NeuAc nLcOse4Cer), with a concomitant decrease in GM3. All these oncogenes are
'extranuclear' type oncogenes, of which the products are expressed in the cytoplasm
or on the cell surface membrane. These results are in striking contrast to those on
the transfection of 'intranuclear' type oncogenes (ex., adeno E1) into the same 3Y1
cells, where GD3 neosynthesis was specifically brought about by the transfection.