Symbol s2m RNA type Cis-reg SO 0000233 | Rfam RF00164 Domain(s) Eukaryota; Viruses | |
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The Coronavirus 3' stem-loop II-like motif (also known as s2m) is a secondary structure motif identified in the 3'untranslated region (3'UTR) of astrovirus, coronavirus and equine rhinovirus genomes. Its function is unknown, but various viral 3' UTR regions have been found to play roles in viral replication and packaging.
This motif appears to be conserved in both nucleotide sequence and secondary structure folding indicating a strong evolutionary selection for its conservation. The presence of this conserved motif in these three different viral families is suggested to be the result of at least two separate recombination events.
Other RNA families identified in the coronavirus include the SL-III cis-acting replication element (CRE), the coronavirus frameshifting stimulation element, the coronavirus packaging signal and the coronavirus 3' UTR pseudoknot.
Biological significance
Functionally during host invasion by viral RNA, it appears that s2m first binds one or more proteins as a mechanism for the viral RNA to substitute host protein synthesis. This has also been seen in s2m RNA macromolecular substitution of ribosomal RNA folds. The s2m RNA element are also effective targets for the design of anti-viral drugs.