| Popis: |
The 2'-5' Oligoadenylate Synthetases (OAS) are a family of IFN-induced proteins, which possess antiviral activity against viruses such as EMCV, WNV and CHIKV. The classical antiviral mechanism of these proteins is mediated through RNase L. RNase L is a potent RNase, which is activated by the 2-5As synthesised by OAS. OAS synthesises 2-5As after recognition of dsRNA, which is typically found during a viral infection. 2-5As are oligoadenylates, which are linked by a phosphodiester bond between the 2' C and the 5' C of the ribose. This unique bond enables RNase L to distinguish these nucleotides from 3'-5' linked nucleotides (RNA and DNA). RNase L binds the 2-5As, which in turn activates this enzyme. Upon activation, RNase L degrades viral and cellular RNA, inhibiting further viral growth in the cell.However, a number of the OAS proteins also possess an alternative mechanism of viral inhibition, which is independent of the 2-5A activity and of RNase L. In this thesis, I have investigated the novel antiviral activity of OAS1. During the course of her PhD studies, Helle Kristiansen carried out research into proteins that play a role in the defence against viral infection in humans and animals. All cells contain a considerable number of proteins that can directly or directly attack a virus and inhibit or completely stop its growth before it has become established and can cause disease. Helle Kristiansen studied one of the proteins, which is called 2'-5'-oligoadenylate synthetase. She helped identify a new function of the protein regarding the way it can inhibit viral growth. The results she achieved contribute to the understanding of the defence against viral infection in humans and animals, and they contribute to the development of new pharmaceuticals targeting viral diseases. |
