Enteroviral 3' UTR elements
editIntroduction
edit(In molecular biology, the enteroviral 3' UTR element is an RNA structure found in the 3' UTR of various enteroviruses.) A UTR, or untranslated region, is a section of mRNA which is not read out in translation and thus does not contribute to the protein sequence.[1] It sequence, and particularly its structure, do have important functions in the cell cycle. (The overall structure forms the origin of replication (OriR) for the initiation of (-) strand RNA synthesis. Pseudoknots have also been predicted in this structure.) These structure are important in virus replication.
Replication
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Enteroviruses replicate through the synthesis of a (-) strand RNA from the (+) strand. The newly synthesized strand acts as a template for new (+) strand progeny RNA. While the same proteins are responsible for the synthesis of both strands they recognize two different 3’ elements on the (+) and (-) strands of enterovirus RNA. Proteins recognize oriL on the 3’ end of the (-) strand to initiate synthesis of the (+) strand and oriR on the (+) strand to initiate (-) strand synthesis.[2] The (+) strand 3’ UTR contains two domains X and Y which have hairpin structures.[3] A so-called kissing interaction is formed between the loops of the X and Y domains and is then stacked on the helical portion of the X domain to form the tertiary structure of oriR.[4] An enterovirus subgroup, B-like enteroviruses, contain an additional domain Z.[5]
The 3’ end of the (+) strand also contains a poly(A) tail that interacts with the kissing domain and is essential for replication.[2] [3] The deletion of this tail proves detrimental to the virus.[2] Interestingly, if the kissing interaction is deleted replication will still occur but mutants with a distorted kissing domain exhibit a temperature sensitive or lethal phenotype.[4] [2] The kissing interaction must exhibit wildtype structure or not be present at all, which raises questions as to its function in replication.
References
edit- ^ http://groups.molbiosci.northwestern.edu/holmgren/Glossary/Definitions/Def-U/UTR.html.
{{cite web}}: Missing or empty|title=(help) - ^ a b c d Zoll, Jan; Heus, Hans A.; Van Kuppeveld, Frank J.M.; Melchers, Willem J.G. (2009). "The structure–function relationship of the enterovirus 3′-UTR". Virus Research. 139 (2): 209–216. doi:10.1016/j.virusres.2008.07.014. PMID 18706945.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: date and year (link) - ^ a b Pilipenko, Evgeny V. (1992). "Towards identification of cis-acting elements involved in the replication of enterovirus and rhinovirus RNAs: a proposal for the existence of tRNA-like terminal structures". Nucleic Acids Research. 20 (7): 1739–1745. doi:10.1093/nar/20.7.1739. PMC 312265. PMID 1315956.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ a b Wang, Jinhua (1999). "Structural requirements of the higher order RNA kissing element in the enteroviral 3′UTR". Nucleic Acids Research. 27 (2): 485–490. doi:10.1093/nar/27.2.485. PMC 148204. PMID 9862969.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help) - ^ Merkle, I. (1 October 2002). "Biological Significance of a Human Enterovirus B-Specific RNA Element in the 3' Nontranslated Region". Journal of Virology. 76 (19): 9900–9909. doi:10.1128/JVI.76.19.9900–9909.2002 (inactive 2023-08-01).
{{cite journal}}: Check|doi=value (help); Unknown parameter|coauthors=ignored (|author=suggested) (help)CS1 maint: DOI inactive as of August 2023 (link)