TEMPERATURE-SENSITIVE HVJ (SENDAI VIRUS) WITH ALTERED P-POLYPEPTIDE DERIVED FROM PERSISTENTLY INFECTED CELL-LINES

HVJ [hemagglutinating virus of Japan] isolated from culture fluids of G2 [human giant tumor], THEL [golden hamster embryonic lung] and GM2 [golden hamster fibrosarcoma] cells persistently infected with HVJ (G2-HVJ, THEL-HVJ and GM2-HVJ) were characterized in comparison with wild-type HVJ (HVJo). Viral structural proteins were analyzed by 10% SDS[sodium dodecyl sulfate]-polyacrylamide gel electrophoresis. Only the P polypeptides of all the HVJ clones isolated from G2-HVJ cells had a smaller size MW of 77,000 (77K) than that of HVJo with a MW of 79K. One of 6 clones from THEL-HVJ cells and 1 of 10 clones from GM2-HVJ cells exhibited the same migration pattern of P polypeptide as that of the clones from G2-HVJ cells. The other structural proteins were not different from those of the wild-type virions. All the clones from these carrier cultures were temperature-sensitive and were blocked in early step(s) required for RNA sunthesis. Some mutations(s) associated with P polypeptide could occur during the course of HVJ persistent infection in cell cultures.