| Popis: |
The molecular mediators of interferon action are those cellular components which change in relative amount upon treatment with interferon. The mediators to be discussed in this chapter are enzymes which are synthesized at an increased rate in interferon-treated cells (Baglioni 1979). It should be pointed out that interferon induces the synthesis of several proteins in mammalian cells (Gupta et al. 1979; Knight and Korant 1979). These proteins can be identified as polypeptides with characteristic electrophoretic mobility by labeling the cells with radioactive amino acids and fractionating cell extracts by electrophoresis. The increase in these proteins is inhibited by actinomycin D, indicating that RNA synthesis is required for their induction by interferon (Farrell et al. 1980). The synthesis of these proteins begins a few hours after tissue culture cells are exposed to interferon, but is is transient, even in the continuous presence of this antiviral agent (Rubin and Gupta 1980). These proteins, however, have not been identified with specific enzymatic activities or cellular components and it is unclear at this time whether or how they are involved in the different activities of interferon. |
