Viral Events Necessary for the Induction of Interferon in Chick Embryo Cells

Abstract

Temperature-sensitive mutants of Sindbis virus were employed to investigate the nature of the viral event(s) which induces chick-embryo cells to produce interferon. Chick embryo cells induced by the parental heat-resistant strain of Sindbis virus produced essentially equal amounts of interferon at 29 and 42 C. An RNAand three RNA+ strains [temperature-sensitive mutants unable (RNA-) and able (RNA+) to make ribonucleic acid] produced interferon at 29 C but not at 42 C. It is concluded that viral RNA per se and the replication of viral RNA do not induce interferon production by chick embryo cells.962 Vol. 2,No. 10

Conditions required for induction of interferon by rotaviruses and for their sensitivity to its action

“…Interferon is induced when a large variety of animal cells are treated with viruses or doublestranded polynucleotides (6,7). However, many attempts to correlate virus dsRNA synthesis with interferon induction have proven inconclusive (1,2,20,21,26). More recently, a detailed study of interferon induction by UV-irradiated reovirus (9) correlated induction with the dsRNA of the input virus.…”

Induction of interferon by virus glycoprotein(s) in lymphoid cells through interaction with the cellular receptors via lectin-like action: An alternative interferon induction mechanism

“…By using temperature-sensitive mutants [4,7,48,65], defective interfering particles [50], UV-inactivated viruses [10,18,53] or cell lines nonpermissive for virus replication, a close relationship between interferon induction and double-stranded RNA was revealed: for instance, the fact that prolonged ultraviolet irradiation disrupts the interferon-inducing ability of a virus suggests that the interferon induction is related to the function of virus nucleic acid. In addition, some of the cellular proteins induced by interferon such as 2-5 A synthetase and a protein kinase are specifically activated by double-stranded RNA, indicating that the interferon system is intimately related to doublestranded RNA.…”

Interferon Induction by Viruses

“…However, synthesis of viral RNA was not sufficient to insure the production of interferon. Thus three different temperature-sensitive mutants of Sindbis virus produced at the nonpermissive temperature 83, 25, and 17%, respectively, as much RNA as the wild type parent virus; but in all cases they induced the production of less than 5% as much interferon (44). We have more recently taken the direct approach and tried to demonstrate interferon production in chick embryo cells with the mixture of the synthetic polynucleotides, polyinosinic acid and polycytidylic acid (poly rI:rC).…”