Question

RNA viruses, especially eukaryotic ones, face problems in getting their mRNAs translated in competition with host mRNAs. What are some ways that eukaryoticRNA viruses have solved this problem? Using examples, describe the various strategies, the genome structures involved and how each strategy works.

Answer 1

The RNA viruses face problem in getting their mRNA translated because they depend on their host for the process of transcription and translation. The viral mRNAs must compete with their host counterparts for the synthesis of protein or mRNA translation. It is because it has limited eukaryotic translation initiation factors which facilitate the recruitment of the ribosome on both the viral and cellular mRNAs. However there are certain strategies that they use to get rid of the complexity:-

The virus makes use of the multiple monocistronic mRNAs for facilitating the process of translation.

The host splicing machinery helps in processing the primary transcripts that are produced by the virus mRNA.

There are special features on the viral mRNA that allows the ribosome to bind internally towards the 5’-end.